EVERSOURCE ENERGY, 10-Q filed on 5/6/2022
Quarterly Report
v3.22.1
COVER PAGE - shares
 3 Months Ended
Mar. 31, 2022
Apr. 30, 2022
Document And Entity [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2022  
Document Transition Report false  
Entity Registrant Name EVERSOURCE ENERGY  
Entity Incorporation, State or Country Code MA  
Entity Address, Address Line One 300 Cadwell Drive  
Entity Address, City or Town Springfield  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 01104  
City Area Code 800  
Local Phone Number 286-5000  
Entity File Number 001-05324  
Entity Tax Identification Number 04-2147929  
Title of 12(b) Security Common Shares, $5.00 par value per share  
Trading Symbol ES  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Smaller Reporting Company false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding (in shares)   344,878,136
Entity Central Index Key 0000072741  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2022  
Document Fiscal Period Focus Q1  
Amendment Flag false  
The Connecticut Light and Power Company    
Document And Entity [Line Items]    
Entity Registrant Name THE CONNECTICUT LIGHT AND POWER COMPANY  
Entity Incorporation, State or Country Code CT  
Entity Address, Address Line One 107 Selden Street  
Entity Address, City or Town Berlin  
Entity Address, State or Province CT  
Entity Address, Postal Zip Code 06037-1616  
City Area Code 800  
Local Phone Number 286-5000  
Entity File Number 000-00404  
Entity Tax Identification Number 06-0303850  
Entity Filer Category Non-accelerated Filer  
Entity Smaller Reporting Company false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding (in shares)   6,035,205
Entity Central Index Key 0000023426  
Current Fiscal Year End Date --12-31  
NSTAR Electric Company    
Document And Entity [Line Items]    
Entity Registrant Name NSTAR ELECTRIC COMPANY  
Entity Incorporation, State or Country Code MA  
Entity Address, Address Line One 800 Boylston Street  
Entity Address, City or Town Boston  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 02199  
City Area Code 800  
Local Phone Number 286-5000  
Entity File Number 001-02301  
Entity Tax Identification Number 04-1278810  
Entity Filer Category Non-accelerated Filer  
Entity Smaller Reporting Company false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding (in shares)   200
Entity Central Index Key 0000013372  
Current Fiscal Year End Date --12-31  
Public Service Company of New Hampshire    
Document And Entity [Line Items]    
Entity Registrant Name PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE  
Entity Incorporation, State or Country Code NH  
Entity Address, Address Line One Energy Park  
Entity Address, Address Line Two 780 North Commercial Street  
Entity Address, City or Town Manchester  
Entity Address, State or Province NH  
Entity Address, Postal Zip Code 03101-1134  
City Area Code 800  
Local Phone Number 286-5000  
Entity File Number 001-06392  
Entity Tax Identification Number 02-0181050  
Entity Filer Category Non-accelerated Filer  
Entity Smaller Reporting Company false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding (in shares)   301
Entity Central Index Key 0000315256  
Current Fiscal Year End Date --12-31  
v3.22.1
CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Current Assets:    
Cash $ 46,175 $ 66,773
Receivables, Net (net of allowance for uncollectible accounts) 1,468,558 1,226,069
Unbilled Revenues 192,913 210,879
Fuel, Materials, Supplies and REC Inventory 287,042 267,547
Regulatory Assets 1,128,088 1,129,093
Prepayments and Other Current Assets 350,907 369,759
Total Current Assets 3,473,683 3,270,120
Property, Plant and Equipment, Net 33,852,596 33,377,650
Deferred Debits and Other Assets:    
Total Long-Term Regulatory Assets 4,573,309 4,586,709
Goodwill 4,477,118 4,477,269
Investments in Unconsolidated Affiliates 1,545,433 1,436,293
Marketable Securities 423,216 460,347
Other Long-Term Assets 943,797 883,756
Total Deferred Debits and Other Assets 11,962,873 11,844,374
Total Assets 49,289,152 48,492,144
Current Liabilities:    
Notes Payable 1,668,800 1,505,450
Long-Term Debt – Current Portion 817,114 1,193,097
Rate Reduction Bonds – Current Portion 43,210 43,210
Accounts Payable 1,494,360 1,672,230
Regulatory Liabilities 652,358 602,432
Other Current Liabilities 925,467 830,620
Total Current Liabilities 5,601,309 5,847,039
Deferred Credits and Other Liabilities:    
Accumulated Deferred Income Taxes 4,683,105 4,597,120
Regulatory Liabilities 3,894,768 3,866,251
Derivative Liabilities 209,548 235,387
Asset Retirement Obligations 500,685 500,111
Accrued Pension, SERP and PBOP 200,614 242,463
Other Long-Term Liabilities 862,304 971,080
Total Deferred Credits and Other Liabilities 10,351,024 10,412,412
Capitalization:    
Long-Term Debt 17,912,462 17,023,577
Rate Reduction Bonds 432,097 453,702
Noncontrolling Interest – Preferred Stock of Subsidiaries 155,570 155,570
Common Shareholders' Equity:    
Common Shares 1,789,092 1,789,092
Capital Surplus, Paid In 8,102,618 8,098,514
Retained Earnings 5,229,069 5,005,391
Accumulated Other Comprehensive Loss (41,571) (42,275)
Treasury Stock (242,518) (250,878)
Common Shareholders' Equity 14,836,690 14,599,844
Commitments and Contingencies (Note 9)
Total Liabilities and Capitalization $ 49,289,152 $ 48,492,144
v3.22.1
CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Statement of Financial Position [Abstract]    
Allowance for uncollectible accounts $ 432,174 $ 417,406
v3.22.1
CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Income Statement [Abstract]    
Operating Revenues $ 3,471,310 $ 2,825,840
Operating Expenses:    
Purchased Power, Fuel and Transmission 1,389,696 998,491
Operations and Maintenance 472,433 465,542
Depreciation 289,330 270,704
Amortization 236,948 108,013
Energy Efficiency Programs 199,484 188,063
Taxes Other Than Income Taxes 220,364 209,459
Total Operating Expenses 2,808,255 2,240,272
Operating Income/(Loss) 663,055 585,568
Interest Expense 153,245 137,766
Other Income, Net 71,561 34,201
Income Before Income Tax Expense 581,371 482,003
Income Tax Expense 136,045 113,980
Net Income 445,326 368,023
Net Income Attributable to Noncontrolling Interests 1,880 1,880
Net Income Attributable to Common Shareholders $ 443,446 $ 366,143
Basic EPS (in dollars per share) $ 1.28 $ 1.07
Diluted EPS (in dollars per share) $ 1.28 $ 1.06
Weighted Average Common Shares Outstanding:    
Basic (in shares) 345,156,346 343,678,243
Diluted (in shares) 345,661,133 344,334,689
v3.22.1
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Statement of Comprehensive Income [Abstract]    
Net Income $ 445,326 $ 368,023
Other Comprehensive Income (Loss), Net of Tax:    
Qualified Cash Flow Hedging Instruments 5 407
Changes in Unrealized Losses on Marketable Securities (817) (736)
Changes in Funded Status of Pension, SERP and PBOP Benefit Plans 1,516 1,517
Net OCI 704 1,188
Comprehensive Income Attributable to Noncontrolling Interests (1,880) (1,880)
Comprehensive Income Attributable to Common Shareholders $ 444,150 $ 367,331
v3.22.1
CONDENSED CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY - USD ($)
$ in Thousands
Total
Common Shares
Capital Surplus, Paid In
Retained Earnings
Accumulated Other Comprehensive Loss
Treasury Stock
Balance (in shares) at Dec. 31, 2020   342,954,023        
Balance at Dec. 31, 2020 $ 14,063,566 $ 1,789,092 $ 8,015,663 $ 4,613,201 $ (76,411) $ (277,979)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net Income 368,023     368,023    
Dividends on Common Stock (206,913)     (206,913)    
Dividends on Preferred Stock (1,880)     (1,880)    
Long-Term Incentive Plan Activity (15,727)   (15,727)      
Issuance of Treasury Shares (in shares)   480,275        
Issuance of Treasury Shares 25,163   16,182     8,981
Other Comprehensive (Loss)/Income, Net of Tax 1,188       1,188  
Balance (in shares) at Mar. 31, 2021   343,434,298        
Balance at Mar. 31, 2021 $ 14,233,420 $ 1,789,092 8,016,118 4,772,431 (75,223) (268,998)
Balance (in shares) at Dec. 31, 2021 344,403,196 344,403,196        
Balance at Dec. 31, 2021 $ 14,599,844 $ 1,789,092 8,098,514 5,005,391 (42,275) (250,878)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net Income 445,326     445,326    
Dividends on Common Stock (219,768)     (219,768)    
Dividends on Preferred Stock (1,880)     (1,880)    
Long-Term Incentive Plan Activity (16,538)   (16,538)      
Issuance of Treasury Shares (in shares)   447,076        
Issuance of Treasury Shares 29,002   20,642     8,360
Other Comprehensive (Loss)/Income, Net of Tax $ 704       704  
Balance (in shares) at Mar. 31, 2022 344,850,272 344,850,272        
Balance at Mar. 31, 2022 $ 14,836,690 $ 1,789,092 $ 8,102,618 $ 5,229,069 $ (41,571) $ (242,518)
v3.22.1
CONDENSED CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Statement of Stockholders' Equity [Abstract]    
Dividends on Common Shares (in dollars per share) $ 0.6375 $ 0.6025
v3.22.1
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Activities:    
Net Income $ 445,326 $ 368,023
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:    
Depreciation 289,330 270,704
Deferred Income Taxes 67,557 41,917
Uncollectible Expense 17,135 16,295
Pension, SERP and PBOP Income, Net (40,642) (2,341)
Pension and PBOP Contributions (26,100) (31,100)
Regulatory (Under)/Over Recoveries, Net (107,767) 28,024
(Customer Credits)/Reserve at CL&P related to PURA Settlement Agreement and Storm Performance Penalty (58,412) 30,000
Amortization 236,948 108,013
Cost of Removal Expenditures (61,660) (39,333)
Other (21,409) (51,913)
Changes in Current Assets and Liabilities:    
Accounts Receivables from Subsidiaries (291,723) (124,344)
Fuel, Materials, Supplies and REC Inventory (19,495) (42,494)
Taxes Receivable/Accrued, Net 56,519 64,076
Accounts Payable (68,909) (181,725)
Other Current Assets and Liabilities, Net (44,758) (42,386)
Net Cash Flows Provided by Operating Activities 371,940 411,416
Investing Activities:    
Investments in Property, Plant and Equipment (764,594) (688,983)
Proceeds from Sales of Marketable Securities 90,409 79,818
Purchases of Marketable Securities (76,182) (68,360)
Investments in Unconsolidated Affiliates, Net (113,856) (34,127)
Other Investing Activities 5,976 7,135
Net Cash Flows Used in Investing Activities (858,247) (704,517)
Financing Activities:    
Cash Dividends on Common Shares (213,890) (201,013)
Cash Dividends on Preferred Stock (1,880) (1,880)
Increase in Notes Payable 163,350 669,919
Repayment of Rate Reduction Bonds (21,605) (21,605)
Issuance of Long-Term Debt 1,300,000 350,000
Retirement of Long-Term Debt (770,000) (572,000)
Other Financing Activities (26,087) (19,666)
Net Cash Flows Provided by/(Used in) Financing Activities 429,888 203,755
Net Decrease in Cash and Restricted Cash (56,419) (89,346)
Cash and Restricted Cash - Beginning of Period 221,008 264,950
Cash and Restricted Cash - End of Period $ 164,589 $ 175,604
v3.22.1
THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED BALANCE SHEETS - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Current Assets:    
Cash $ 46,175 $ 66,773
Receivables, Net (net of allowance for uncollectible accounts) 1,468,558 1,226,069
Unbilled Revenues 192,913 210,879
Fuel, Materials, Supplies and REC Inventory 287,042 267,547
Regulatory Assets 1,128,088 1,129,093
Prepayments and Other Current Assets 350,907 369,759
Total Current Assets 3,473,683 3,270,120
Property, Plant and Equipment, Net 33,852,596 33,377,650
Deferred Debits and Other Assets:    
Total Long-Term Regulatory Assets 4,573,309 4,586,709
Other Long-Term Assets 943,797 883,756
Total Deferred Debits and Other Assets 11,962,873 11,844,374
Total Assets 49,289,152 48,492,144
Current Liabilities:    
Long-Term Debt – Current Portion 817,114 1,193,097
Accounts Payable 1,494,360 1,672,230
Regulatory Liabilities 652,358 602,432
Other Current Liabilities 925,467 830,620
Total Current Liabilities 5,601,309 5,847,039
Deferred Credits and Other Liabilities:    
Accumulated Deferred Income Taxes 4,683,105 4,597,120
Regulatory Liabilities 3,894,768 3,866,251
Derivative Liabilities 209,548 235,387
Other Long-Term Liabilities 862,304 971,080
Total Deferred Credits and Other Liabilities 10,351,024 10,412,412
Capitalization:    
Long-Term Debt 17,912,462 17,023,577
Noncontrolling Interest – Preferred Stock of Subsidiaries 155,570 155,570
Common Shareholders' Equity:    
Common Shares 1,789,092 1,789,092
Capital Surplus, Paid In 8,102,618 8,098,514
Retained Earnings 5,229,069 5,005,391
Accumulated Other Comprehensive Income (41,571) (42,275)
Common Shareholders' Equity 14,836,690 14,599,844
Commitments and Contingencies (Note 9)
Total Liabilities and Capitalization 49,289,152 48,492,144
The Connecticut Light and Power Company    
Current Assets:    
Cash 21,628 55,804
Receivables, Net (net of allowance for uncollectible accounts) 567,718 447,774
Accounts Receivable from Affiliated Companies 46,852 43,944
Unbilled Revenues 50,515 56,787
Fuel, Materials, Supplies and REC Inventory 65,196 60,264
Regulatory Assets 382,112 371,609
Prepayments and Other Current Assets 95,710 120,257
Total Current Assets 1,229,731 1,156,439
Property, Plant and Equipment, Net 10,941,005 10,803,543
Deferred Debits and Other Assets:    
Total Long-Term Regulatory Assets 1,681,057 1,713,161
Other Long-Term Assets 287,028 276,513
Total Deferred Debits and Other Assets 1,968,085 1,989,674
Total Assets 14,138,821 13,949,656
Current Liabilities:    
Long-Term Debt – Current Portion 400,000 0
Accounts Payable 514,385 533,454
Accounts Payable to Affiliated Companies 126,363 132,578
Regulatory Liabilities 251,555 266,489
Derivative Liabilities 74,428 73,528
Other Current Liabilities 174,210 141,955
Total Current Liabilities 1,540,941 1,148,004
Deferred Credits and Other Liabilities:    
Accumulated Deferred Income Taxes 1,588,370 1,562,102
Regulatory Liabilities 1,208,297 1,193,259
Derivative Liabilities 209,548 235,387
Other Long-Term Liabilities 181,850 179,824
Total Deferred Credits and Other Liabilities 3,188,065 3,170,572
Capitalization:    
Long-Term Debt 3,815,662 4,215,379
Noncontrolling Interest – Preferred Stock of Subsidiaries 116,200 116,200
Common Shareholders' Equity:    
Common Shares 60,352 60,352
Capital Surplus, Paid In 3,110,765 3,010,765
Retained Earnings 2,306,620 2,228,133
Accumulated Other Comprehensive Income 216 251
Common Shareholders' Equity 5,477,953 5,299,501
Commitments and Contingencies (Note 9)
Total Liabilities and Capitalization $ 14,138,821 $ 13,949,656
v3.22.1
THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED BALANCE SHEETS (Parenthetical) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Allowance for uncollectible accounts $ 432,174 $ 417,406
The Connecticut Light and Power Company    
Allowance for uncollectible accounts $ 180,524 $ 181,319
v3.22.1
THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Revenues $ 3,471,310 $ 2,825,840
Operating Expenses:    
Purchased Power, Fuel and Transmission 1,389,696 998,491
Operations and Maintenance 472,433 465,542
Depreciation 289,330 270,704
Energy Efficiency Programs 199,484 188,063
Taxes Other Than Income Taxes 220,364 209,459
Total Operating Expenses 2,808,255 2,240,272
Operating Income/(Loss) 663,055 585,568
Interest Expense 153,245 137,766
Other Income, Net 71,561 34,201
Income Before Income Tax Expense 581,371 482,003
Income Tax Expense 136,045 113,980
Net Income 445,326 368,023
The Connecticut Light and Power Company    
Operating Revenues 1,285,831 987,274
Operating Expenses:    
Purchased Power, Fuel and Transmission 523,463 373,274
Operations and Maintenance 157,061 175,420
Depreciation 87,265 83,405
Amortization of Regulatory Assets, Net 169,749 62,775
Energy Efficiency Programs 35,397 35,573
Taxes Other Than Income Taxes 90,373 91,392
Total Operating Expenses 1,063,308 821,839
Operating Income/(Loss) 222,523 165,435
Interest Expense 40,586 38,979
Other Income, Net 19,564 4,908
Income Before Income Tax Expense 201,501 131,364
Income Tax Expense 48,524 32,966
Net Income $ 152,977 $ 98,398
v3.22.1
THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF COMPREHENSIVE INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Net Income $ 445,326 $ 368,023
Other Comprehensive Income (Loss), Net of Tax:    
Qualified Cash Flow Hedging Instruments 5 407
Changes in Unrealized Losses on Marketable Securities (817) (736)
Net OCI 704 1,188
Comprehensive Income Attributable to Common Shareholders 444,150 367,331
The Connecticut Light and Power Company    
Net Income 152,977 98,398
Other Comprehensive Income (Loss), Net of Tax:    
Qualified Cash Flow Hedging Instruments (7) (7)
Changes in Unrealized Losses on Marketable Securities (28) (25)
Net OCI (35) (32)
Comprehensive Income Attributable to Common Shareholders $ 152,942 $ 98,366
v3.22.1
THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($)
$ in Thousands
Total
Common Stock
Capital Surplus, Paid In
Retained Earnings
Accumulated Other Comprehensive Loss
The Connecticut Light and Power Company
The Connecticut Light and Power Company
Common Stock
The Connecticut Light and Power Company
Capital Surplus, Paid In
The Connecticut Light and Power Company
Retained Earnings
The Connecticut Light and Power Company
Accumulated Other Comprehensive Loss
Balance (in shares) at Dec. 31, 2020   342,954,023         6,035,205      
Balance at Dec. 31, 2020 $ 14,063,566 $ 1,789,092 $ 8,015,663 $ 4,613,201 $ (76,411) $ 5,044,786 $ 60,352 $ 2,810,765 $ 2,173,367 $ 302
Increase (Decrease) in Stockholders' Equity [Roll Forward]                    
Net Income 368,023     368,023   98,398     98,398  
Dividends on Preferred Stock (1,880)     (1,880)   (1,390)     (1,390)  
Dividends on Common Stock (206,913)     (206,913)   (70,100)     (70,100)  
Other Comprehensive Loss 1,188       1,188 (32)       (32)
Balance (in shares) at Mar. 31, 2021   343,434,298         6,035,205      
Balance at Mar. 31, 2021 $ 14,233,420 $ 1,789,092 8,016,118 4,772,431 (75,223) 5,071,662 $ 60,352 2,810,765 2,200,275 270
Balance (in shares) at Dec. 31, 2021 344,403,196 344,403,196         6,035,205      
Balance at Dec. 31, 2021 $ 14,599,844 $ 1,789,092 8,098,514 5,005,391 (42,275) 5,299,501 $ 60,352 3,010,765 2,228,133 251
Increase (Decrease) in Stockholders' Equity [Roll Forward]                    
Net Income 445,326     445,326   152,977     152,977  
Dividends on Preferred Stock (1,880)     (1,880)   (1,390)     (1,390)  
Dividends on Common Stock (219,768)     (219,768)   (73,100)     (73,100)  
Capital Contributions from Eversource Parent           100,000   100,000    
Other Comprehensive Loss $ 704       704 (35)       (35)
Balance (in shares) at Mar. 31, 2022 344,850,272 344,850,272         6,035,205      
Balance at Mar. 31, 2022 $ 14,836,690 $ 1,789,092 $ 8,102,618 $ 5,229,069 $ (41,571) $ 5,477,953 $ 60,352 $ 3,110,765 $ 2,306,620 $ 216
v3.22.1
THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Activities:    
Net Income $ 445,326 $ 368,023
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:    
Depreciation 289,330 270,704
Deferred Income Taxes 67,557 41,917
Uncollectible Expense 17,135 16,295
Pension, SERP and PBOP (Income)/Expense, Net (40,642) (2,341)
Pension and PBOP Contributions (26,100) (31,100)
Regulatory (Under)/Over Recoveries, Net (107,767) 28,024
(Customer Credits)/Reserve at CL&P related to PURA Settlement Agreement and Storm Performance Penalty (58,412) 30,000
Cost of Removal Expenditures (61,660) (39,333)
Other (21,409) (51,913)
Changes in Current Assets and Liabilities:    
Receivables and Unbilled Revenues, Net (291,723) (124,344)
Taxes Receivable/Accrued, Net 56,519 64,076
Accounts Payable (68,909) (181,725)
Other Current Assets and Liabilities, Net (44,758) (42,386)
Net Cash Flows Provided by Operating Activities 371,940 411,416
Investing Activities:    
Investments in Property, Plant and Equipment (764,594) (688,983)
Other Investing Activities 5,976 7,135
Net Cash Flows Used in Investing Activities (858,247) (704,517)
Financing Activities:    
Cash Dividends on Common Shares (213,890) (201,013)
Cash Dividends on Preferred Stock (1,880) (1,880)
Other Financing Activities (26,087) (19,666)
Net Cash Flows Provided by/(Used in) Financing Activities 429,888 203,755
Net Decrease in Cash and Restricted Cash (56,419) (89,346)
Cash and Restricted Cash - Beginning of Period 221,008 264,950
Cash and Restricted Cash - End of Period 164,589 175,604
The Connecticut Light and Power Company    
Operating Activities:    
Net Income 152,977 98,398
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:    
Depreciation 87,265 83,405
Deferred Income Taxes 19,627 25,354
Uncollectible Expense 3,776 3,797
Pension, SERP and PBOP (Income)/Expense, Net (7,330) 3,088
Pension and PBOP Contributions 0 (18,940)
Regulatory (Under)/Over Recoveries, Net (162,474) (59,971)
(Customer Credits)/Reserve at CL&P related to PURA Settlement Agreement and Storm Performance Penalty (58,412) 30,000
Amortization of Regulatory Assets, Net 169,749 62,775
Cost of Removal Expenditures (16,684) (17,293)
Other (9,357) (12,777)
Changes in Current Assets and Liabilities:    
Receivables and Unbilled Revenues, Net (125,429) (66,930)
Taxes Receivable/Accrued, Net 67,708 29,596
Accounts Payable 38,010 17,124
Other Current Assets and Liabilities, Net (24,143) (21,433)
Net Cash Flows Provided by Operating Activities 135,283 156,193
Investing Activities:    
Investments in Property, Plant and Equipment (205,343) (197,954)
Other Investing Activities 346 80
Net Cash Flows Used in Investing Activities (204,997) (197,874)
Financing Activities:    
Cash Dividends on Common Shares (73,100) (70,100)
Cash Dividends on Preferred Stock (1,390) (1,390)
Capital Contributions from Eversource Parent 100,000 0
Increase in Notes Payable to Eversource Parent 0 32,100
Other Financing Activities 0 (450)
Net Cash Flows Provided by/(Used in) Financing Activities 25,510 (39,840)
Net Decrease in Cash and Restricted Cash (44,204) (81,521)
Cash and Restricted Cash - Beginning of Period 74,788 99,809
Cash and Restricted Cash - End of Period $ 30,584 $ 18,288
v3.22.1
NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Current Assets:    
Cash $ 46,175 $ 66,773
Receivables, Net (net of allowance for uncollectible accounts) 1,468,558 1,226,069
Unbilled Revenues 192,913 210,879
Fuel, Materials, Supplies and REC Inventory 287,042 267,547
Regulatory Assets 1,128,088 1,129,093
Prepayments and Other Current Assets 350,907 369,759
Total Current Assets 3,473,683 3,270,120
Property, Plant and Equipment, Net 33,852,596 33,377,650
Deferred Debits and Other Assets:    
Total Long-Term Regulatory Assets 4,573,309 4,586,709
Other Long-Term Assets 943,797 883,756
Total Deferred Debits and Other Assets 11,962,873 11,844,374
Total Assets 49,289,152 48,492,144
Current Liabilities:    
Notes Payable 1,668,800 1,505,450
Long-Term Debt – Current Portion 817,114 1,193,097
Accounts Payable 1,494,360 1,672,230
Regulatory Liabilities 652,358 602,432
Other Current Liabilities 925,467 830,620
Total Current Liabilities 5,601,309 5,847,039
Deferred Credits and Other Liabilities:    
Accumulated Deferred Income Taxes 4,683,105 4,597,120
Regulatory Liabilities 3,894,768 3,866,251
Other Long-Term Liabilities 862,304 971,080
Total Deferred Credits and Other Liabilities 10,351,024 10,412,412
Capitalization:    
Long-Term Debt 17,912,462 17,023,577
Preferred Stock Not Subject to Mandatory Redemption 155,570 155,570
Common Shareholders' Equity:    
Common Shares 1,789,092 1,789,092
Capital Surplus, Paid In 8,102,618 8,098,514
Retained Earnings 5,229,069 5,005,391
Accumulated Other Comprehensive Income (41,571) (42,275)
Common Shareholders' Equity 14,836,690 14,599,844
Commitments and Contingencies (Note 9)
Total Liabilities and Capitalization 49,289,152 48,492,144
NSTAR Electric Company    
Current Assets:    
Cash 721 745
Receivables, Net (net of allowance for uncollectible accounts) 417,048 405,674
Accounts Receivable from Affiliated Companies 45,121 67,420
Unbilled Revenues 36,618 37,497
Fuel, Materials, Supplies and REC Inventory 148,084 116,712
Taxes Receivable 35,318 80,617
Regulatory Assets 433,653 443,956
Prepayments and Other Current Assets 25,465 22,397
Total Current Assets 1,142,028 1,175,018
Property, Plant and Equipment, Net 11,008,899 10,876,614
Deferred Debits and Other Assets:    
Total Long-Term Regulatory Assets 1,239,773 1,135,231
Prepaid Pension and PBOP 475,602 441,426
Other Long-Term Assets 171,421 171,657
Total Deferred Debits and Other Assets 1,886,796 1,748,314
Total Assets 14,037,723 13,799,946
Current Liabilities:    
Notes Payable 275,000 162,500
Notes Payable to Eversource Parent 4,000 0
Long-Term Debt – Current Portion 400,000 400,000
Accounts Payable 437,896 490,915
Accounts Payable to Affiliated Companies 139,762 129,575
Obligations to Third Party Suppliers 127,342 116,273
Renewable Portfolio Standards Compliance Obligations 129,759 100,200
Regulatory Liabilities 279,299 228,248
Other Current Liabilities 157,567 84,303
Total Current Liabilities 1,950,625 1,712,014
Deferred Credits and Other Liabilities:    
Accumulated Deferred Income Taxes 1,617,909 1,579,508
Regulatory Liabilities 1,570,969 1,559,072
Other Long-Term Liabilities 275,573 347,934
Total Deferred Credits and Other Liabilities 3,464,451 3,486,514
Capitalization:    
Long-Term Debt 3,586,326 3,585,399
Preferred Stock Not Subject to Mandatory Redemption 43,000 43,000
Common Shareholders' Equity:    
Common Shares 0 0
Capital Surplus, Paid In 2,253,942 2,253,942
Retained Earnings 2,738,925 2,718,576
Accumulated Other Comprehensive Income 454 501
Common Shareholders' Equity 4,993,321 4,973,019
Commitments and Contingencies (Note 9)
Total Liabilities and Capitalization $ 14,037,723 $ 13,799,946
v3.22.1
NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Allowance for uncollectible accounts $ 432,174 $ 417,406
NSTAR Electric    
Allowance for uncollectible accounts $ 94,775 $ 97,005
v3.22.1
NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Revenues $ 3,471,310 $ 2,825,840
Operating Expenses:    
Purchased Power, Fuel and Transmission 1,389,696 998,491
Operations and Maintenance 472,433 465,542
Depreciation 289,330 270,704
Energy Efficiency Programs 199,484 188,063
Taxes Other Than Income Taxes 220,364 209,459
Total Operating Expenses 2,808,255 2,240,272
Operating Income/(Loss) 663,055 585,568
Interest Expense 153,245 137,766
Other Income, Net 71,561 34,201
Income Before Income Tax Expense 581,371 482,003
Income Tax Expense 136,045 113,980
Net Income 445,326 368,023
NSTAR Electric Company    
Operating Revenues 863,176 737,043
Operating Expenses:    
Purchased Power, Fuel and Transmission 313,748 226,478
Operations and Maintenance 164,862 143,219
Depreciation 89,033 82,793
Amortization of Regulatory Assets, Net 29,345 18,418
Energy Efficiency Programs 80,232 75,099
Taxes Other Than Income Taxes 59,774 54,652
Total Operating Expenses 736,994 600,659
Operating Income/(Loss) 126,182 136,384
Interest Expense 38,222 32,306
Other Income, Net 29,231 16,812
Income Before Income Tax Expense 117,191 120,890
Income Tax Expense 24,452 26,966
Net Income $ 92,739 $ 93,924
v3.22.1
NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Net Income $ 445,326 $ 368,023
Other Comprehensive Income (Loss), Net of Tax:    
Changes in Funded Status of Pension, SERP and PBOP Benefit Plans 1,516 1,517
Qualified Cash Flow Hedging Instruments 5 407
Changes in Unrealized Losses on Marketable Securities (817) (736)
Net OCI 704 1,188
Comprehensive Income Attributable to Common Shareholders 444,150 367,331
NSTAR Electric Company    
Net Income 92,739 93,924
Other Comprehensive Income (Loss), Net of Tax:    
Changes in Funded Status of Pension, SERP and PBOP Benefit Plans (44) (41)
Qualified Cash Flow Hedging Instruments 5 109
Changes in Unrealized Losses on Marketable Securities (8) (7)
Net OCI (47) 61
Comprehensive Income Attributable to Common Shareholders $ 92,692 $ 93,985
v3.22.1
NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($)
$ in Thousands
Total
Common Stock
Capital Surplus, Paid In
Retained Earnings
Accumulated Other Comprehensive Loss
NSTAR Electric
NSTAR Electric
Common Stock
NSTAR Electric
Capital Surplus, Paid In
NSTAR Electric
Retained Earnings
NSTAR Electric
Accumulated Other Comprehensive Loss
Balance (in shares) at Dec. 31, 2020   342,954,023         200      
Balance at Dec. 31, 2020 $ 14,063,566 $ 1,789,092 $ 8,015,663 $ 4,613,201 $ (76,411) $ 4,521,418 $ 0 $ 1,993,942 $ 2,527,167 $ 309
Increase (Decrease) in Stockholders' Equity [Roll Forward]                    
Net Income 368,023     368,023   93,924     93,924  
Dividends on Preferred Stock (1,880)     (1,880)   (490)     (490)  
Dividends on Common Stock (206,913)     (206,913)   (206,400)     (206,400)  
Other Comprehensive (Loss)/Income, Net of Tax 1,188       1,188 61       61
Balance (in shares) at Mar. 31, 2021   343,434,298         200      
Balance at Mar. 31, 2021 $ 14,233,420 $ 1,789,092 8,016,118 4,772,431 (75,223) 4,408,513 $ 0 1,993,942 2,414,201 370
Balance (in shares) at Dec. 31, 2021 344,403,196 344,403,196         200      
Balance at Dec. 31, 2021 $ 14,599,844 $ 1,789,092 8,098,514 5,005,391 (42,275) 4,973,019 $ 0 2,253,942 2,718,576 501
Increase (Decrease) in Stockholders' Equity [Roll Forward]                    
Net Income 445,326     445,326   92,739     92,739  
Dividends on Preferred Stock (1,880)     (1,880)   (490)     (490)  
Dividends on Common Stock (219,768)     (219,768)   (71,900)     (71,900)  
Other Comprehensive (Loss)/Income, Net of Tax $ 704       704 (47)       (47)
Balance (in shares) at Mar. 31, 2022 344,850,272 344,850,272         200      
Balance at Mar. 31, 2022 $ 14,836,690 $ 1,789,092 $ 8,102,618 $ 5,229,069 $ (41,571) $ 4,993,321 $ 0 $ 2,253,942 $ 2,738,925 $ 454
v3.22.1
NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Activities:    
Net Income $ 445,326 $ 368,023
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:    
Depreciation 289,330 270,704
Deferred Income Taxes 67,557 41,917
Uncollectible Expense 17,135 16,295
Pension and PBOP Contributions (26,100) (31,100)
Regulatory (Under)/Over Recoveries, Net (107,767) 28,024
Cost of Removal Expenditures (61,660) (39,333)
Other (21,409) (51,913)
Changes in Current Assets and Liabilities:    
Accounts Receivables from Subsidiaries (291,723) (124,344)
Fuel, Materials, Supplies and REC Inventory (19,495) (42,494)
Taxes Receivable/Accrued, Net 56,519 64,076
Accounts Payable (68,909) (181,725)
Other Current Assets and Liabilities, Net (44,758) (42,386)
Net Cash Flows Provided by Operating Activities 371,940 411,416
Investing Activities:    
Investments in Property, Plant and Equipment (764,594) (688,983)
Other Investing Activities 5,976 7,135
Net Cash Flows Used in Investing Activities (858,247) (704,517)
Financing Activities:    
Cash Dividends on Common Shares (213,890) (201,013)
Cash Dividends on Preferred Stock (1,880) (1,880)
Increase in Notes Payable 163,350 669,919
Other Financing Activities (26,087) (19,666)
Net Cash Flows Provided by/(Used in) Financing Activities 429,888 203,755
Net Decrease in Cash and Restricted Cash (56,419) (89,346)
Cash and Restricted Cash - Beginning of Period 221,008 264,950
Cash and Restricted Cash - End of Period 164,589 175,604
NSTAR Electric    
Operating Activities:    
Net Income 92,739 93,924
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:    
Depreciation 89,033 82,793
Deferred Income Taxes 26,857 10,309
Uncollectible Expense 4,662 3,868
Pension, SERP and PBOP Expense, Net of Contributions (13,742) (6,335)
Pension and PBOP Contributions (5,000) 0
Regulatory (Under)/Over Recoveries, Net (10,813) (3,405)
Amortization of Regulatory Assets, Net 29,345 18,418
Cost of Removal Expenditures (12,852) (10,224)
Other (5,531) (13,362)
Changes in Current Assets and Liabilities:    
Accounts Receivables from Subsidiaries 2,051 (14,587)
Fuel, Materials, Supplies and REC Inventory (31,372) (52,998)
Taxes Receivable/Accrued, Net 45,299 58,353
Accounts Payable (55,743) (45,604)
Other Current Assets and Liabilities, Net 34,931 51,445
Net Cash Flows Provided by Operating Activities 189,864 172,595
Investing Activities:    
Investments in Property, Plant and Equipment (234,120) (215,483)
Other Investing Activities 96 22
Net Cash Flows Used in Investing Activities (234,024) (215,461)
Financing Activities:    
Cash Dividends on Common Shares (71,900) (206,400)
Cash Dividends on Preferred Stock (490) (490)
Increase in Notes Payable to Eversource Parent 4,000 1,200
Increase in Notes Payable 112,500 248,500
Other Financing Activities 15 19
Net Cash Flows Provided by/(Used in) Financing Activities 44,125 42,829
Net Decrease in Cash and Restricted Cash (35) (37)
Cash and Restricted Cash - Beginning of Period 18,179 17,410
Cash and Restricted Cash - End of Period $ 18,144 $ 17,373
v3.22.1
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Current Assets:    
Cash $ 46,175 $ 66,773
Receivables, Net (net of allowance for uncollectible accounts) 1,468,558 1,226,069
Unbilled Revenues 192,913 210,879
Fuel, Materials, Supplies and REC Inventory 287,042 267,547
Regulatory Assets 1,128,088 1,129,093
Prepayments and Other Current Assets 350,907 369,759
Total Current Assets 3,473,683 3,270,120
Property, Plant and Equipment, Net 33,852,596 33,377,650
Deferred Debits and Other Assets:    
Total Long-Term Regulatory Assets 4,573,309 4,586,709
Other Long-Term Assets 943,797 883,756
Total Deferred Debits and Other Assets 11,962,873 11,844,374
Total Assets 49,289,152 48,492,144
Current Liabilities:    
Rate Reduction Bonds – Current Portion 43,210 43,210
Accounts Payable 1,494,360 1,672,230
Regulatory Liabilities 652,358 602,432
Other Current Liabilities 925,467 830,620
Total Current Liabilities 5,601,309 5,847,039
Deferred Credits and Other Liabilities:    
Accumulated Deferred Income Taxes 4,683,105 4,597,120
Regulatory Liabilities 3,894,768 3,866,251
Other Long-Term Liabilities 862,304 971,080
Total Deferred Credits and Other Liabilities 10,351,024 10,412,412
Capitalization:    
Long-Term Debt 17,912,462 17,023,577
Rate Reduction Bonds 432,097 453,702
Common Shareholders' Equity:    
Common Shares 1,789,092 1,789,092
Capital Surplus, Paid In 8,102,618 8,098,514
Retained Earnings 5,229,069 5,005,391
Accumulated Other Comprehensive Loss (41,571) (42,275)
Common Shareholders' Equity 14,836,690 14,599,844
Commitments and Contingencies (Note 9)
Total Liabilities and Capitalization 49,289,152 48,492,144
PSNH    
Current Assets:    
Cash 3,827 15
Receivables, Net (net of allowance for uncollectible accounts) 148,542 124,232
Accounts Receivable from Affiliated Companies 17,271 17,156
Unbilled Revenues 51,490 53,937
Fuel, Materials, Supplies and REC Inventory 31,963 25,930
Regulatory Assets 124,701 107,169
Special Deposits 16,557 31,390
Prepayments and Other Current Assets 8,387 22,109
Total Current Assets 402,738 381,938
Property, Plant and Equipment, Net 3,722,618 3,656,462
Deferred Debits and Other Assets:    
Total Long-Term Regulatory Assets 654,507 679,182
Other Long-Term Assets 22,513 23,202
Total Deferred Debits and Other Assets 677,020 702,384
Total Assets 4,802,376 4,740,784
Current Liabilities:    
Notes Payable to Eversource Parent 196,400 110,600
Rate Reduction Bonds – Current Portion 43,210 43,210
Accounts Payable 157,876 166,452
Accounts Payable to Affiliated Companies 41,508 43,485
Regulatory Liabilities 106,393 120,176
Other Current Liabilities 64,356 63,005
Total Current Liabilities 609,743 546,928
Deferred Credits and Other Liabilities:    
Accumulated Deferred Income Taxes 545,593 537,978
Regulatory Liabilities 388,838 381,366
Other Long-Term Liabilities 49,844 64,264
Total Deferred Credits and Other Liabilities 984,275 983,608
Capitalization:    
Long-Term Debt 1,164,010 1,163,833
Rate Reduction Bonds 432,097 453,702
Common Shareholders' Equity:    
Common Shares 0 0
Capital Surplus, Paid In 1,088,134 1,088,134
Retained Earnings 524,142 504,556
Accumulated Other Comprehensive Loss (25) 23
Common Shareholders' Equity 1,612,251 1,592,713
Commitments and Contingencies (Note 9)
Total Liabilities and Capitalization $ 4,802,376 $ 4,740,784
v3.22.1
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Allowance for uncollectible accounts $ 432,174 $ 417,406
PSNH    
Allowance for uncollectible accounts $ 26,164 $ 24,331
v3.22.1
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Revenues $ 3,471,310 $ 2,825,840
Operating Expenses:    
Purchased Power, Fuel and Transmission 1,389,696 998,491
Operations and Maintenance 472,433 465,542
Depreciation 289,330 270,704
Energy Efficiency Programs 199,484 188,063
Taxes Other Than Income Taxes 220,364 209,459
Total Operating Expenses 2,808,255 2,240,272
Operating Income/(Loss) 663,055 585,568
Interest Expense 153,245 137,766
Other Income, Net 71,561 34,201
Income Before Income Tax Expense 581,371 482,003
Income Tax Expense 136,045 113,980
Net Income 445,326 368,023
PSNH    
Operating Revenues 339,427 293,435
Operating Expenses:    
Purchased Power, Fuel and Transmission 125,844 91,609
Operations and Maintenance 59,573 54,664
Depreciation 31,253 29,468
Amortization of Regulatory Assets, Net 26,834 18,547
Energy Efficiency Programs 8,718 10,348
Taxes Other Than Income Taxes 22,785 22,149
Total Operating Expenses 275,007 226,785
Operating Income/(Loss) 64,420 66,650
Interest Expense 13,645 14,630
Other Income, Net 7,509 4,166
Income Before Income Tax Expense 58,284 56,186
Income Tax Expense 12,698 11,510
Net Income $ 45,586 $ 44,676
v3.22.1
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Net Income $ 445,326 $ 368,023
Other Comprehensive Income (Loss), Net of Tax:    
Qualified Cash Flow Hedging Instruments 5 407
Changes in Unrealized Losses on Marketable Securities (817) (736)
Net OCI 704 1,188
Comprehensive Income Attributable to Common Shareholders 444,150 367,331
PSNH    
Net Income 45,586 44,676
Other Comprehensive Income (Loss), Net of Tax:    
Qualified Cash Flow Hedging Instruments 0 298
Changes in Unrealized Losses on Marketable Securities (48) (43)
Net OCI (48) 255
Comprehensive Income Attributable to Common Shareholders $ 45,538 $ 44,931
v3.22.1
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($)
$ in Thousands
Total
Common Stock
Capital Surplus, Paid In
Retained Earnings
Accumulated Other Comprehensive Loss
PSNH
PSNH
Common Stock
PSNH
Capital Surplus, Paid In
PSNH
Retained Earnings
PSNH
Accumulated Other Comprehensive Loss
Balance (in shares) at Dec. 31, 2020   342,954,023         301      
Balance at Dec. 31, 2020 $ 14,063,566 $ 1,789,092 $ 8,015,663 $ 4,613,201 $ (76,411) $ 1,542,539 $ 0 $ 928,134 $ 615,018 $ (613)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                    
Net Income 368,023     368,023   44,676     44,676  
Dividends on Common Stock (206,913)     (206,913)   (25,200)     (25,200)  
Other Comprehensive (Loss)/Income, Net of Tax 1,188       1,188 255       255
Balance (in shares) at Mar. 31, 2021   343,434,298         301      
Balance at Mar. 31, 2021 $ 14,233,420 $ 1,789,092 8,016,118 4,772,431 (75,223) 1,562,270 $ 0 928,134 634,494 (358)
Balance (in shares) at Dec. 31, 2021 344,403,196 344,403,196         301      
Balance at Dec. 31, 2021 $ 14,599,844 $ 1,789,092 8,098,514 5,005,391 (42,275) 1,592,713 $ 0 1,088,134 504,556 23
Increase (Decrease) in Stockholders' Equity [Roll Forward]                    
Net Income 445,326     445,326   45,586     45,586  
Dividends on Common Stock (219,768)     (219,768)   (26,000)     (26,000)  
Other Comprehensive (Loss)/Income, Net of Tax $ 704       704 (48)       (48)
Balance (in shares) at Mar. 31, 2022 344,850,272 344,850,272         301      
Balance at Mar. 31, 2022 $ 14,836,690 $ 1,789,092 $ 8,102,618 $ 5,229,069 $ (41,571) $ 1,612,251 $ 0 $ 1,088,134 $ 524,142 $ (25)
v3.22.1
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Activities:    
Net Income $ 445,326 $ 368,023
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:    
Depreciation 289,330 270,704
Deferred Income Taxes 67,557 41,917
Uncollectible Expense 17,135 16,295
Regulatory Over/(Underrecoveries), Net (107,767) 28,024
Pension, SERP and PBOP (Income)/Expense, Net (40,642) (2,341)
Cost of Removal Expenditures (61,660) (39,333)
Other (21,409) (51,913)
Changes in Current Assets and Liabilities:    
Receivables and Unbilled Revenues, Net (291,723) (124,344)
Materials, Supplies and REC Inventory (19,495) (42,494)
Taxes Receivable/Accrued, Net 56,519 64,076
Accounts Payable (68,909) (181,725)
Other Current Assets and Liabilities, Net (44,758) (42,386)
Net Cash Flows Provided by Operating Activities 371,940 411,416
Investing Activities:    
Investments in Property, Plant and Equipment (764,594) (688,983)
Other Investing Activities 5,976 7,135
Net Cash Flows Used in Investing Activities (858,247) (704,517)
Financing Activities:    
Cash Dividends on Common Shares (213,890) (201,013)
Retirement of Long-Term Debt (770,000) (572,000)
Repayment of Rate Reduction Bonds (21,605) (21,605)
Other Financing Activities (26,087) (19,666)
Net Cash Flows Provided by/(Used in) Financing Activities 429,888 203,755
Net Decrease in Cash and Restricted Cash (56,419) (89,346)
Cash and Restricted Cash - Beginning of Period 221,008 264,950
Cash and Restricted Cash - End of Period 164,589 175,604
PSNH    
Operating Activities:    
Net Income 45,586 44,676
Adjustments to Reconcile Net Income to Net Cash Flows Provided by Operating Activities:    
Depreciation 31,253 29,468
Deferred Income Taxes 7,480 (378)
Uncollectible Expense 2,496 1,221
Regulatory Over/(Underrecoveries), Net (32,186) (14,645)
Amortization of Regulatory Assets, Net 26,834 18,547
Pension, SERP and PBOP (Income)/Expense, Net (3,997) (935)
Cost of Removal Expenditures (7,131) (5,154)
Other (4,631) (565)
Changes in Current Assets and Liabilities:    
Receivables and Unbilled Revenues, Net (25,972) 3,223
Materials, Supplies and REC Inventory (6,033) (2,296)
Taxes Receivable/Accrued, Net 8,067 9,867
Accounts Payable 9,389 (21,025)
Other Current Assets and Liabilities, Net 6,928 12,897
Net Cash Flows Provided by Operating Activities 58,083 74,901
Investing Activities:    
Investments in Property, Plant and Equipment (107,916) (68,278)
Other Investing Activities 593 137
Net Cash Flows Used in Investing Activities (107,323) (68,141)
Financing Activities:    
Cash Dividends on Common Shares (26,000) (25,200)
Retirement of Long-Term Debt 0 (122,000)
Repayment of Rate Reduction Bonds (21,605) (21,605)
Increase in Notes Payable to Eversource Parent 85,800 150,500
Other Financing Activities (23) (22)
Net Cash Flows Provided by/(Used in) Financing Activities 38,172 (18,327)
Net Decrease in Cash and Restricted Cash (11,068) (11,567)
Cash and Restricted Cash - Beginning of Period 35,126 39,555
Cash and Restricted Cash - End of Period $ 24,058 $ 27,988
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
 3 Months Ended
Mar. 31, 2022
Accounting Policies [Abstract]  
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
A.    Basis of Presentation
Eversource Energy is a public utility holding company primarily engaged, through its wholly-owned regulated utility subsidiaries, in the energy delivery business.  Eversource Energy's wholly-owned regulated utility subsidiaries consist of CL&P, NSTAR Electric and PSNH (electric utilities), Yankee Gas, NSTAR Gas and Eversource Gas Company of Massachusetts (EGMA) (natural gas utilities) and Aquarion (water utilities). Eversource provides energy delivery and/or water service to approximately 4.4 million electric, natural gas and water customers through ten regulated utilities in Connecticut, Massachusetts and New Hampshire.

The unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH include the accounts of each of their respective subsidiaries.  Intercompany transactions have been eliminated in consolidation.  The accompanying unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH and the unaudited condensed financial statements of CL&P are herein collectively referred to as the "financial statements."

The combined notes to the financial statements have been prepared pursuant to the rules and regulations of the SEC.  Certain information and footnote disclosures included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to such rules and regulations.  The accompanying financial statements should be read in conjunction with the Combined Notes to Financial Statements included in Item 8, "Financial Statements and Supplementary Data," of the Eversource 2021 Form 10-K, which was filed with the SEC on February 17, 2022. The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.  Actual results could differ from those estimates.

The financial statements contain, in the opinion of management, all adjustments (including normal, recurring adjustments) necessary to present fairly Eversource's, CL&P's, NSTAR Electric's and PSNH's financial position as of March 31, 2022 and December 31, 2021, and the results of operations, comprehensive income, common shareholders' equity and cash flows for the three months ended March 31, 2022 and 2021. The results of operations, comprehensive income and cash flows for the three months ended March 31, 2022 and 2021 are not necessarily indicative of the results expected for a full year.  

CYAPC and YAEC are inactive regional nuclear power companies engaged in the long-term storage of their spent nuclear fuel. Eversource consolidates the operations of CYAPC and YAEC because CL&P's, NSTAR Electric's and PSNH's combined ownership and voting interests in each of these entities is greater than 50 percent.  Intercompany transactions between CL&P, NSTAR Electric, PSNH and the CYAPC and YAEC companies have been eliminated in consolidation of the Eversource financial statements.

Eversource holds several equity ownership interests that are not consolidated and are accounted for under the equity method.

Eversource's utility subsidiaries' electric, natural gas and water distribution and transmission businesses are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for entities with rate-regulated operations, which considers the effect of regulation on the differences in the timing of the recognition of certain revenues and expenses from those of other businesses and industries. See Note 2, "Regulatory Accounting," for further information.

Certain reclassifications of prior period data were made in the accompanying financial statements to conform to the current period presentation.

On May 4, 2022, Eversource announced that it had initiated a strategic review of its offshore wind investment portfolio. As part of that review, Eversource will explore strategic alternatives that could result in a potential sale of all, or part, of its 50 percent interest in its offshore wind partnership with Ørsted. Eversource expects to complete this review during 2022. Eversource’s offshore wind business includes a 50 percent ownership interest in North East Offshore, which holds PPAs and contracts for the Revolution Wind, South Fork Wind and Sunrise Wind projects, as well as undeveloped offshore lease area. As of March 31, 2022 and December 31, 2021, Eversource's total equity investment balance in its offshore wind business was $1.33 billion and $1.21 billion, respectively. Eversource’s initiation of the strategic review of its offshore wind investment does not impact the March 31, 2022 financial statements, and at this time, Eversource cannot predict the ultimate outcome or estimate the potential impact of such review.
B.    Allowance for Uncollectible Accounts
Receivables, Net on the balance sheets primarily includes trade receivables from retail customers and customers related to wholesale transmission contracts, wholesale market sales, sales of RECs, and property rentals. Receivables, Net also includes customer receivables for the purchase of electricity from a competitive third party supplier, the current portion of customer energy efficiency loans, property damage receivables and other miscellaneous receivables. There is no material concentration of receivables. Receivables are recorded at amortized cost, net of a credit loss provision (or allowance for uncollectible accounts).

Receivables are presented net of expected credit losses at estimated net realizable value by maintaining an allowance for uncollectible accounts. The current expected credit loss (CECL) model is applied to receivables for purposes of calculating the allowance for uncollectible accounts. This model is based on expected losses and results in the recognition of estimated expected credit losses, including uncollectible amounts for both billed and unbilled revenues, over the life of the receivable at the time a receivable is recorded.

The allowance for uncollectible accounts is determined based upon a variety of judgments and factors, including an aging-based quantitative assessment that applies an estimated uncollectible percentage to each receivable aging category.  Factors in determining credit loss include historical collection, write-off experience, analysis of delinquency statistics, and management's assessment of collectability from customers, including current conditions, customer payment trends, the impact on customer bills because of energy usage trends and changes in rates, flexible payment plans and financial hardship arrearage management programs being offered to customers, reasonable forecasts, and expectations of future collectability and collection efforts. Management continuously assesses the collectability of receivables and adjusts estimates based on actual experience and future expectations based on economic conditions, collection efforts and other factors.  Management also monitors the aging analysis of receivables to determine if there are changes in the collections of accounts receivable. Receivable balances are written off against the allowance for uncollectible accounts when the customer accounts are no longer in service and these balances are deemed to be uncollectible. Management concluded that the reserve balance as of March 31, 2022 adequately reflected the collection risk and net realizable value for its receivables.

As of March 31, 2022 and December 31, 2021, the total amount incurred as a result of COVID-19 included in the allowance for uncollectible accounts was $58.5 million and $55.3 million at Eversource, $20.4 million and $23.9 million at CL&P, and $9.0 million and $9.0 million at NSTAR Electric, respectively. At our Connecticut and Massachusetts utilities, the COVID-19 related uncollectible amounts were deferred either as incremental regulatory costs or deferred through existing regulatory tracking mechanisms that recover uncollectible energy supply costs, as management believes it is probable that these costs will ultimately be recovered from customers in future rates. No COVID-19 related uncollectible amounts were deferred at PSNH as a result of a July 2021 NHPUC order. Based on the status of our COVID-19 regulatory dockets, and policies and practices in the jurisdictions in which we operate, we believe our state regulatory commissions in Connecticut and Massachusetts will allow us to recover our incremental uncollectible customer receivable costs associated with COVID-19.

The PURA allows CL&P and Yankee Gas to accelerate the recovery of accounts receivable balances attributable to qualified customers under financial or medical duress (uncollectible hardship accounts receivable) outstanding for greater than 180 days and 90 days, respectively.  The DPU allows NSTAR Electric, NSTAR Gas and EGMA to recover in rates amounts associated with certain uncollectible hardship accounts receivable. These uncollectible hardship customer account balances are included in Regulatory Assets or Other Long-Term Assets on the balance sheets. Hardship customers are protected from shut-off in certain circumstances, and historical collection experience has reflected a higher default risk as compared to the rest of the receivable population. Management uses a higher credit risk profile for this pool of trade receivables as compared to non-hardship receivables. The allowance for uncollectible hardship accounts is included in the total uncollectible allowance balance.

The total allowance for uncollectible accounts is included in Receivables, Net on the balance sheets. The activity in the allowance for uncollectible accounts by portfolio segment as of March 31st is as follows:
EversourceCL&PNSTAR ElectricPSNH
(Millions of Dollars)Hardship AccountsRetail (Non-Hardship),
Wholesale, and Other		Total AllowanceHardship AccountsRetail (Non-Hardship),
Wholesale, and Other		Total AllowanceHardship AccountsRetail (Non-Hardship),
Wholesale, and Other		Total AllowanceTotal Allowance
Three Months Ended 2022
Beginning Balance$226.1 $191.3 $417.4 $144.6 $36.7 $181.3 $43.3 $53.7 $97.0 $24.3 
Uncollectible Expense— 17.1 17.1 — 3.8 3.8 — 4.7 4.7 2.5 
Uncollectible Costs Deferred (1)
0.9 14.8 15.7 (4.0)(2.1)(6.1)(3.3)5.4 2.1 1.0 
Write-Offs(2.3)(22.0)(24.3)(1.1)(0.5)(1.6)(0.3)(10.6)(10.9)(1.8)
Recoveries Collected0.8 5.5 6.3 0.6 2.5 3.1 — 1.9 1.9 0.2 
Ending Balance$225.5 $206.7 $432.2 $140.1 $40.4 $180.5 $39.7 $55.1 $94.8 $26.2 
Three Months Ended 2021
Beginning Balance$194.8 $164.1 $358.9 $129.1 $28.3 $157.4 $39.7 $51.9 $91.6 $17.2 
Uncollectible Expense— 16.3 16.3 — 3.8 3.8 — 3.9 3.9 1.2 
Uncollectible Costs Deferred (1)
5.4 27.1 32.5 11.9 7.5 19.4 (8.5)8.4 (0.1)1.2 
Write-Offs(3.3)(16.7)(20.0)(2.9)(4.0)(6.9)(0.1)(7.5)(7.6)(2.5)
Recoveries Collected0.4 3.6 4.0 0.3 1.1 1.4 — 1.5 1.5 0.2 
Ending Balance$197.3 $194.4 $391.7 $138.4 $36.7 $175.1 $31.1 $58.2 $89.3 $17.3 
(1) These expected credit losses are deferred as regulatory costs on the balance sheets, as these amounts are ultimately recovered in rates. Amounts include uncollectible costs for hardship accounts and other customer receivables, including uncollectible amounts related to uncollectible energy supply costs and COVID-19.

C.    Fair Value Measurements
Fair value measurement guidance is applied to derivative contracts that are not elected or designated as "normal purchases" or "normal sales" (normal) and to the marketable securities held in trusts.  Fair value measurement guidance is also applied to valuations of the investments used to calculate the funded status of pension and PBOP plans, the nonrecurring fair value measurements of nonfinancial assets such as goodwill, long-lived assets, equity method investments, AROs, and in the valuation of acquisitions. The fair value measurement guidance was also applied in estimating the fair value of preferred stock, long-term debt and RRBs.

Fair Value Hierarchy:  In measuring fair value, Eversource uses observable market data when available in order to minimize the use of unobservable inputs.  Inputs used in fair value measurements are categorized into three fair value hierarchy levels for disclosure purposes.  The entire fair value measurement is categorized based on the lowest level of input that is significant to the fair value measurement.  Eversource evaluates the classification of assets and liabilities measured at fair value on a quarterly basis. The levels of the fair value hierarchy are described below:

Level 1 - Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities as of the reporting date.  Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.  

Level 2 - Inputs are quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs are observable.

Level 3 - Quoted market prices are not available.  Fair value is derived from valuation techniques in which one or more significant inputs or assumptions are unobservable.  Where possible, valuation techniques incorporate observable market inputs that can be validated to external sources such as industry exchanges, including prices of energy and energy-related products.  

Uncategorized - Investments that are measured at net asset value are not categorized within the fair value hierarchy.

Determination of Fair Value:  The valuation techniques and inputs used in Eversource's fair value measurements are described in Note 4, "Derivative Instruments," Note 5, "Marketable Securities," and Note 10, "Fair Value of Financial Instruments," to the financial statements.

D.    Other Income, Net
The components of Other Income, Net on the statements of income were as follows:
 For the Three Months Ended
 March 31, 2022March 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR ElectricPSNHEversourceCL&PNSTAR ElectricPSNH
Pension, SERP and PBOP Non-Service
   Income Components		$54.3 $15.9 $21.0 $6.6 $20.1 $2.7 $10.1 $2.7 
AFUDC Equity9.9 2.8 4.9 0.4 9.2 1.7 6.2 0.6 
Equity in Earnings of Unconsolidated Affiliates0.4 — — — 3.7 — 0.1 — 
Investment (Loss)/Income(0.2)(0.4)(0.3)0.2 (0.6)0.4 0.2 0.1 
Interest Income6.7 1.3 3.5 0.3 1.5 0.1 0.1 0.7 
Other0.5 — 0.1 — 0.3 — 0.1 0.1 
Total Other Income, Net$71.6 $19.6 $29.2 $7.5 $34.2 $4.9 $16.8 $4.2 

E.    Other Taxes
Eversource's companies that serve customers in Connecticut collect gross receipts taxes levied by the state of Connecticut from their customers. These gross receipts taxes are recorded separately with collections in Operating Revenues and with payments in Taxes Other Than Income Taxes on the statements of income as follows:
 For the Three Months Ended
(Millions of Dollars)March 31, 2022March 31, 2021
Eversource$48.6 $48.6 
CL&P37.8 39.2 

As agents for state and local governments, Eversource's companies that serve customers in Connecticut and Massachusetts collect certain sales taxes that are recorded on a net basis with no impact on the statements of income. 
F.    Supplemental Cash Flow Information
Non-cash investing activities include plant additions included in Accounts Payable as follows:
(Millions of Dollars)As of March 31, 2022As of March 31, 2021
Eversource$385.6 $262.9 
CL&P102.1 70.9 
NSTAR Electric85.8 68.2 
PSNH49.5 23.5 

The following table reconciles cash as reported on the balance sheets to the cash and restricted cash balance as reported on the statements of cash flows:
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR ElectricPSNHEversourceCL&PNSTAR ElectricPSNH
Cash as reported on the Balance Sheets$46.2 $21.6 $0.7 $3.8 $66.8 $55.8 $0.7 $— 
Restricted cash included in:
Special Deposits73.3 8.7 17.3 16.6 78.2 18.7 17.4 31.4 
Marketable Securities26.0 0.3 0.1 0.5 31.3 0.3 0.1 0.5 
Other Long-Term Assets19.1 — — 3.2 44.7 — — 3.2 
Cash and Restricted Cash as reported on the
    Statements of Cash Flows
$164.6 $30.6 $18.1 $24.1 $221.0 $74.8 $18.2 $35.1 

Special Deposits represent cash collections related to the PSNH RRB customer charges that are held in trust, required ISO-NE cash deposits, and CYAPC and YAEC cash balances. The December 31, 2021 balance also included a $10 million customer assistance fund to provide bill payment assistance to certain existing non-hardship and hardship customers carrying arrearages at CL&P established under the terms of the PURA-approved October 2021 settlement agreement. Those customers were provided with $10 million of bill forgiveness in the first quarter of 2022, which represented a non-cash transaction. Special Deposits are included in Current Assets on the balance sheets. Restricted cash included in Marketable Securities represents money market funds held in trusts to fund certain non-qualified executive benefits and restricted trusts to fund CYAPC and YAEC's spent nuclear fuel storage obligations.

Restricted cash also includes an Energy Relief Fund for energy efficiency and clean energy measures in the Merrimack Valley and an additional energy efficiency program established under the terms of the EGMA 2020 settlement agreement. As of March 31, 2022, $20.0 million of this restricted cash was recorded as short-term in Special Deposits and $15.9 million was recorded in Other Long-Term Assets. As of December 31, 2021, this restricted cash totaled $41.5 million and was recorded in Other Long-Term Assets on the balance sheet.
v3.22.1
REGULATORY ACCOUNTING
 3 Months Ended
Mar. 31, 2022
Regulated Operations [Abstract]  
REGULATORY ACCOUNTING REGULATORY ACCOUNTING
Eversource's utility companies are subject to rate regulation that is based on cost recovery and meets the criteria for application of accounting guidance for rate-regulated operations, which considers the effect of regulation on the timing of the recognition of certain revenues and expenses. The regulated companies' financial statements reflect the effects of the rate-making process.  The rates charged to the customers of Eversource's regulated companies are designed to collect each company's costs to provide service, plus a return on investment.

The application of accounting guidance for rate-regulated enterprises results in recording regulatory assets and liabilities. Regulatory assets represent the deferral of incurred costs that are probable of future recovery in customer rates. Regulatory assets are amortized as the incurred costs are recovered through customer rates. Regulatory liabilities represent either revenues received from customers to fund expected costs that have not yet been incurred or probable future refunds to customers.

Management believes it is probable that each of the regulated companies will recover its respective investments in long-lived assets and the regulatory assets that have been recorded.  If management were to determine that it could no longer apply the accounting guidance applicable to rate-regulated enterprises, or if management could not conclude it is probable that costs would be recovered from customers in future rates, the applicable costs would be charged to net income in the period in which the determination is made.
Regulatory Assets:  The components of regulatory assets were as follows:
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
Benefit Costs$1,452.5 $268.0 $386.9 $116.5 $1,481.0 $272.4 $395.5 $118.9 
Storm Costs, Net1,249.3 735.7 449.4 64.2 1,102.7 695.6 341.3 65.8 
Regulatory Tracking Mechanisms937.7 295.2 375.0 97.0 1,050.5 333.6 376.6 85.4 
Income Taxes, Net791.2 471.8 112.8 14.5 790.7 470.5 112.6 17.5 
Securitized Stranded Costs468.1 — — 468.1 478.9 — — 478.9 
Goodwill-related293.6 — 252.1 — 297.8 — 255.7 — 
Derivative Liabilities229.4 229.4 — — 249.2 249.2 — — 
Asset Retirement Obligations117.5 34.2 61.9 4.2 115.0 33.6 59.8 4.1 
Other Regulatory Assets162.1 28.9 35.4 14.7 150.0 29.9 37.7 15.8 
Total Regulatory Assets5,701.4 2,063.2 1,673.5 779.2 5,715.8 2,084.8 1,579.2 786.4 
Less:  Current Portion1,128.1 382.1 433.7 124.7 1,129.1 371.6 444.0 107.2 
Total Long-Term Regulatory Assets$4,573.3 $1,681.1 $1,239.8 $654.5 $4,586.7 $1,713.2 $1,135.2 $679.2 

Regulatory Costs in Long-Term Assets:  Eversource's regulated companies had $262.5 million (including $113.4 million for CL&P, $84.2 million for NSTAR Electric and $3.4 million for PSNH) and $252.5 million (including $114.9 million for CL&P, $85.0 million for NSTAR Electric and $3.4 million for PSNH) of additional regulatory costs as of March 31, 2022 and December 31, 2021, respectively, that were included in long-term assets on the balance sheets.  These amounts represent incurred costs for which recovery has not yet been specifically approved by the applicable regulatory agency.  However, based on regulatory policies or past precedent on similar costs, management believes it is probable that these costs will ultimately be approved and recovered from customers in rates.

As of March 31, 2022 and December 31, 2021, these regulatory costs included incremental COVID-19 related non-tracked uncollectible expense deferred of $35.0 million and $33.0 million at Eversource, $15.3 million and $18.0 million at CL&P, and $6.1 million and $6.1 million at NSTAR Electric, respectively.

Regulatory Liabilities:  The components of regulatory liabilities were as follows:
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
EDIT due to Tax Cuts and Jobs Act of 2017$2,665.7 $992.7 $973.3 $356.1 $2,685.2 $996.1 $984.5 $359.2 
Cost of Removal667.2 108.6 388.2 19.1 649.6 100.1 381.0 17.2 
Regulatory Tracking Mechanisms571.8 226.7 237.2 94.9 448.4 182.0 185.1 107.0 
Benefit Costs128.3 — 103.1 — 133.5 — 107.4 — 
AFUDC - Transmission85.1 44.0 41.1 — 81.0 43.2 37.8 — 
CL&P Settlement Agreement and Storm
  Performance Penalty		12.9 12.9 — — 81.3 81.3 — — 
Other Regulatory Liabilities416.2 75.0 107.4 25.1 389.7 57.1 91.5 18.2 
Total Regulatory Liabilities4,547.2 1,459.9 1,850.3 495.2 4,468.7 1,459.8 1,787.3 501.6 
Less:  Current Portion652.4 251.6 279.3 106.4 602.4 266.5 228.2 120.2 
Total Long-Term Regulatory Liabilities$3,894.8 $1,208.3 $1,571.0 $388.8 $3,866.3 $1,193.3 $1,559.1 $381.4 
v3.22.1
PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION
 3 Months Ended
Mar. 31, 2022
Property, Plant and Equipment [Abstract]  
PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION
The following tables summarize property, plant and equipment by asset category:
EversourceAs of March 31, 2022As of December 31, 2021
(Millions of Dollars)
Distribution - Electric$17,809.0 $17,679.1 
Distribution - Natural Gas6,713.7 6,694.8 
Transmission - Electric13,011.0 12,882.4 
Distribution - Water1,924.9 1,900.9 
Solar 200.9 200.9 
Utility39,659.5 39,358.1 
Other (1)
1,509.6 1,469.5 
Property, Plant and Equipment, Gross41,169.1 40,827.6 
Less:  Accumulated Depreciation  
Utility   (8,976.2)(8,885.2)
Other(609.8)(580.1)
Total Accumulated Depreciation(9,586.0)(9,465.3)
Property, Plant and Equipment, Net31,583.1 31,362.3 
Construction Work in Progress2,269.5 2,015.4 
Total Property, Plant and Equipment, Net$33,852.6 $33,377.7 
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)CL&PNSTAR
Electric		PSNHCL&PNSTAR
Electric		PSNH
Distribution - Electric$7,188.9 $8,151.1 $2,509.3 $7,117.6 $8,105.5 $2,496.2 
Transmission - Electric5,912.5 5,137.1 1,963.1 5,859.0 5,090.5 1,934.6 
Solar— 200.9 — — 200.9 — 
Property, Plant and Equipment, Gross
13,101.4 13,489.1 4,472.4 12,976.6 13,396.9 4,430.8 
Less:  Accumulated Depreciation
(2,592.6)(3,271.8)(912.8)(2,572.1)(3,227.3)(908.4)
Property, Plant and Equipment, Net
10,508.8 10,217.3 3,559.6 10,404.5 10,169.6 3,522.4 
Construction Work in Progress
432.2 791.6 163.0 399.0 707.0 134.1 
Total Property, Plant and Equipment, Net
$10,941.0 $11,008.9 $3,722.6 $10,803.5 $10,876.6 $3,656.5 

(1)    These assets are primarily comprised of computer software, hardware and equipment at Eversource Service and buildings at The Rocky River Realty Company.
v3.22.1
DERIVATIVE INSTRUMENTS
 3 Months Ended
Mar. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
DERIVATIVE INSTRUMENTS DERIVATIVE INSTRUMENTS
The electric and natural gas companies purchase and procure energy and energy-related products, which are subject to price volatility, for their customers.  The costs associated with supplying energy to customers are recoverable from customers in future rates.  These regulated companies manage the risks associated with the price volatility of energy and energy-related products through the use of derivative and non-derivative contracts.  

Many of the derivative contracts meet the definition of, and are designated as, normal and qualify for accrual accounting under the applicable accounting guidance.  The costs and benefits of derivative contracts that meet the definition of normal are recognized in Operating Expenses on the statements of income as electricity or natural gas is delivered.

Derivative contracts that are not designated as normal are recorded at fair value as current or long-term Derivative Assets or Derivative Liabilities on the balance sheets.  For the electric and natural gas companies, regulatory assets or regulatory liabilities are recorded to offset the fair values of derivatives, as contract settlement amounts are recovered from, or refunded to, customers in their respective energy supply rates.  

The gross fair values of derivative assets and liabilities with the same counterparty are offset and reported as net Derivative Assets or Derivative Liabilities, with current and long-term portions, on the balance sheets.  The following table presents the gross fair values of contracts, categorized by risk type, and the net amounts recorded as current or long-term derivative assets or liabilities:
 As of March 31, 2022As of December 31, 2021
CL&P
(Millions of Dollars)
Fair Value HierarchyCommodity Supply and Price Risk
Management
Netting (1)
Net Amount
Recorded as a Derivative		Commodity Supply and Price Risk
Management
Netting (1)
Net Amount
Recorded as
a Derivative
Current Derivative AssetsLevel 3$14.8 $(0.4)$14.4 $14.7 $(1.0)$13.7 
Long-Term Derivative AssetsLevel 341.4 (1.3)40.1 46.9 (0.9)46.0 
Current Derivative LiabilitiesLevel 3(74.4)— (74.4)(73.5)— (73.5)
Long-Term Derivative LiabilitiesLevel 3(209.5)— (209.5)(235.4)— (235.4)
    
(1)    Amounts represent derivative assets and liabilities that Eversource elected to record net on the balance sheets.  These amounts are subject to master netting agreements or similar agreements for which the right of offset exists.

Derivative Contracts at Fair Value with Offsetting Regulatory Amounts
Commodity Supply and Price Risk Management:  As required by regulation, CL&P, along with UI, has capacity-related contracts with generation facilities.  CL&P has a sharing agreement with UI, with 80 percent of the costs or benefits of each contract borne by or allocated to CL&P and 20 percent borne by or allocated to UI.  The combined capacities of these contracts as of both March 31, 2022 and December 31, 2021 were 675 MW. The capacity contracts extend through 2026 and obligate both CL&P and UI to make or receive payments on a monthly basis to or from the generation facilities based on the difference between a set capacity price and the capacity market price received in the ISO-NE capacity markets. 

For the three months ended March 31, 2022 and 2021, there were gains of $6.2 million and losses of $11.1 million, respectively, deferred as regulatory costs, which reflect the change in fair value associated with Eversource's derivative contracts.

Fair Value Measurements of Derivative Instruments
The fair value of derivative contracts classified as Level 3 utilizes both significant observable and unobservable inputs.  The fair value is modeled using income techniques, such as discounted cash flow valuations adjusted for assumptions related to exit price.  Valuations of derivative contracts using a discounted cash flow methodology include assumptions regarding the timing and likelihood of scheduled payments and also reflect non-performance risk, including credit, using the default probability approach based on the counterparty's credit rating for assets and the Company's credit rating for liabilities.  Significant observable inputs for valuations of these contracts include energy-related product prices in future years for which quoted prices in an active market exist. Valuations incorporate estimates of premiums or discounts that would be required by a market participant to arrive at an exit price, using historical market transactions adjusted for the terms of the contract.  Fair value measurements categorized in Level 3 of the fair value hierarchy are prepared by individuals with expertise in valuation techniques, pricing of energy-related products, and accounting requirements.

The following is a summary of the significant unobservable inputs utilized in the valuations of the derivative contracts classified as Level 3:
 As of March 31, 2022As of December 31, 2021
CL&PRangeAveragePeriod CoveredRangeAveragePeriod Covered
Forward Reserve Prices$0.50 —$1.15$0.82 per kW-Month2022 - 2024$0.50 —$1.15$0.82 per kW-Month2022 - 2024

Exit price premiums of 4.5 percent through 8.8 percent, or a weighted average of 7.7 percent, are also Level 3 significant unobservable inputs applied to these contracts and reflect the uncertainty and illiquidity premiums that would be required based on the most recent market activity available for similar type contracts. The risk premium was weighted by the relative fair value of the net derivative instruments.

As of December 31, 2021, Level 3 unobservable inputs also utilized in the valuation of CL&P’s capacity-related contracts included capacity prices of $2.61 per kW-Month over the period 2025 through 2026. As of March 31, 2022, these capacity price inputs are now observable.

Significant increases or decreases in future capacity or forward reserve prices in isolation would decrease or increase, respectively, the fair value of the derivative liability.  Any increases in risk premiums would increase the fair value of the derivative liability.  Changes in these fair values are recorded as a regulatory asset or liability and do not impact net income.  

The following table presents changes in the Level 3 category of derivative assets and derivative liabilities measured at fair value on a recurring basis.  The derivative assets and liabilities are presented on a net basis.
CL&PFor the Three Months Ended March 31,
(Millions of Dollars)20222021
Derivatives, Net:
Fair Value as of Beginning of Period$(249.2)$(293.1)
Net Realized/Unrealized Gains/(Losses) Included in Regulatory Assets6.2 (12.5)
Settlements13.6 12.5 
Fair Value as of End of Period$(229.4)$(293.1)
v3.22.1
MARKETABLE SECURITIES
 3 Months Ended
Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]  
MARKETABLE SECURITIES MARKETABLE SECURITIES
Eversource holds marketable securities that are primarily used to fund certain non-qualified executive benefits.  The trusts that hold these marketable securities are not subject to regulatory oversight by state or federal agencies.  Eversource’s marketable securities also include CYAPC and YAEC legally restricted trusts that each hold equity and available-for-sale debt securities to fund the spent nuclear fuel removal obligations of their nuclear fuel storage facilities. Equity and available-for-sale debt marketable securities are recorded at fair value, with the current portion recorded in Prepayments and Other Current Assets and the long-term portion recorded in Marketable Securities on the balance sheets.

Equity Securities: Unrealized gains and losses on equity securities held in Eversource's non-qualified executive benefit trust are recorded in Other Income, Net on the statements of income. The fair value of these equity securities as of March 31, 2022 and December 31, 2021 was $31.5 million and $40.2 million, respectively.  For the three months ended March 31, 2022 and 2021, there were unrealized losses of $4.4 million and unrealized gains of $1.1 million recorded in Other Income, Net related to these equity securities, respectively.
Eversource's equity securities also include CYAPC's and YAEC's marketable securities held in spent nuclear fuel trusts, which had fair values of $195.5 million and $214.0 million as of March 31, 2022 and December 31, 2021, respectively.  Unrealized gains and losses for these spent nuclear fuel trusts are subject to regulatory accounting treatment and are recorded in Marketable Securities with the corresponding offset to long-term liabilities on the balance sheets, with no impact on the statements of income.

Available-for-Sale Debt Securities: The following is a summary of the available-for-sale debt securities:
As of March 31, 2022As of December 31, 2021
Eversource
(Millions of Dollars)
Amortized CostPre-Tax
Unrealized Gains		Pre-Tax
Unrealized
Losses		Fair ValueAmortized CostPre-Tax
Unrealized Gains		Pre-Tax
Unrealized
Losses		Fair Value
Debt Securities$211.4 $0.5 $(3.6)$208.3 $214.5 $5.1 $(0.2)$219.4 

Eversource's debt securities include CYAPC's and YAEC's marketable securities held in spent nuclear fuel trusts in the amounts of $183.4 million and $189.9 million as of March 31, 2022 and December 31, 2021, respectively.

Unrealized gains and losses on available-for-sale debt securities held in Eversource's non-qualified benefit trust are recorded in Accumulated Other Comprehensive Income, excluding amounts related to credit losses or losses on securities intended to be sold, which are recorded in Other Income, Net. There have been no significant unrealized losses and no credit losses for the three months ended March 31, 2022 and 2021, and no allowance for credit losses as of March 31, 2022. Factors considered in determining whether a credit loss exists include adverse conditions specifically affecting the issuer, the payment history, ratings and rating changes of the security, and the severity of the impairment.  For asset-backed debt securities, underlying collateral and expected future cash flows are also evaluated. Debt securities included in Eversource's non-qualified benefit trust portfolio are investment-grade bonds with a lower default risk based on their credit quality.

As of March 31, 2022, the contractual maturities of available-for-sale debt securities were as follows:
 
Eversource
(Millions of Dollars)
Amortized CostFair Value
Less than one year (1)
$27.0 $27.0 
One to five years61.9 61.6 
Six to ten years36.3 35.5 
Greater than ten years86.2 84.2 
Total Debt Securities$211.4 $208.3 

(1)    Amounts in the Less than one year category include securities in the CYAPC and YAEC spent nuclear fuel trusts, which are restricted and are classified in long-term Marketable Securities on the balance sheets.

Realized Gains and Losses:  Realized gains and losses are recorded in Other Income, Net for Eversource's benefit trust and are offset in long-term liabilities for CYAPC and YAEC.  Eversource utilizes the specific identification basis method for the Eversource non-qualified benefit trust, and the average cost basis method for the CYAPC and YAEC spent nuclear fuel trusts to compute the realized gains and losses on the sale of marketable securities.

Fair Value Measurements:  The following table presents the marketable securities recorded at fair value on a recurring basis by the level in which they are classified within the fair value hierarchy:
Eversource
(Millions of Dollars)
As of March 31, 2022As of December 31, 2021
Level 1:    
Mutual Funds and Equities$227.0 $254.2 
Money Market Funds26.0 31.3 
Total Level 1$253.0 $285.5 
Level 2:  
U.S. Government Issued Debt Securities (Agency and Treasury)$80.0 $81.3 
Corporate Debt Securities62.5 65.3 
Asset-Backed Debt Securities11.6 12.6 
Municipal Bonds11.7 12.3 
Other Fixed Income Securities16.5 16.6 
Total Level 2$182.3 $188.1 
Total Marketable Securities$435.3 $473.6 
U.S. government issued debt securities are valued using market approaches that incorporate transactions for the same or similar bonds and adjustments for yields and maturity dates.  Corporate debt securities are valued using a market approach, utilizing recent trades of the same or similar instruments and also incorporating yield curves, credit spreads and specific bond terms and conditions.  Asset-backed debt securities include collateralized mortgage obligations, commercial mortgage backed securities, and securities collateralized by auto loans, credit card loans or receivables.  Asset-backed debt securities are valued using recent trades of similar instruments, prepayment assumptions, yield curves, issuance and maturity dates, and tranche information.  Municipal bonds are valued using a market approach that incorporates reported trades and benchmark yields.  Other fixed income securities are valued using pricing models, quoted prices of securities with similar characteristics, and discounted cash flows.
v3.22.1
SHORT-TERM AND LONG-TERM DEBT
 3 Months Ended
Mar. 31, 2022
Debt Disclosure [Abstract]  
SHORT-TERM AND LONG-TERM DEBT SHORT-TERM AND LONG-TERM DEBT
Short-Term Debt - Commercial Paper Programs and Credit Agreements: Eversource parent has a $2.00 billion commercial paper program allowing Eversource parent to issue commercial paper as a form of short-term debt. Eversource parent, CL&P, PSNH, NSTAR Gas, Yankee Gas, EGMA and Aquarion Water Company of Connecticut are parties to a five-year $2.00 billion revolving credit facility, which terminates on October 15, 2026. This revolving credit facility serves to backstop Eversource parent's $2.00 billion commercial paper program.  

NSTAR Electric has a $650 million commercial paper program allowing NSTAR Electric to issue commercial paper as a form of short-term debt. NSTAR Electric is also a party to a five-year $650 million revolving credit facility, which terminates on October 15, 2026. The revolving credit facility serves to backstop NSTAR Electric's $650 million commercial paper program.  

The amount of borrowings outstanding and available under the commercial paper programs were as follows:
Borrowings Outstanding as ofAvailable Borrowing Capacity as ofWeighted-Average Interest Rate as of
March 31, 2022December 31, 2021March 31, 2022December 31, 2021March 31, 2022December 31, 2021
(Millions of Dollars)
Eversource Parent Commercial Paper Program $1,393.8 $1,343.0 $606.2 $657.0 0.93 %0.31 %
NSTAR Electric Commercial Paper Program 275.0 162.5 375.0 487.5 0.43 %0.14 %

There were no borrowings outstanding on the revolving credit facilities as of March 31, 2022 or December 31, 2021.

CL&P and PSNH have uncommitted line of credit agreements totaling $450 million and $300 million, respectively, which will expire on May 12, 2022. There are no borrowings outstanding on either the CL&P or PSNH uncommitted line of credit agreements as of March 31, 2022.

Amounts outstanding under the commercial paper programs are included in Notes Payable and classified in current liabilities on the Eversource and NSTAR Electric balance sheets, as all borrowings are outstanding for no more than 364 days at one time.

The Company expects the future operating cash flows of Eversource, CL&P, NSTAR Electric and PSNH, along with existing borrowing availability and access to both debt and equity markets, will be sufficient to meet any working capital and future operating requirements, and capital investment forecasted opportunities.

Intercompany Borrowings: Eversource parent uses its available capital resources to provide loans to its subsidiaries to assist in meeting their short-term borrowing needs. Eversource parent records intercompany interest income from its loans to subsidiaries, which is eliminated in consolidation. Intercompany loans from Eversource parent to its subsidiaries are eliminated in consolidation on Eversource's balance sheets. As of March 31, 2022, there were intercompany loans from Eversource parent to PSNH of $196.4 million and to a subsidiary of NSTAR Electric of $4.0 million. As of December 31, 2021, there were intercompany loans from Eversource parent to PSNH of $110.6 million. Intercompany loans from Eversource parent are included in Notes Payable to Eversource Parent and classified in current liabilities on the respective subsidiary's balance sheets.

Long-Term Debt Issuances and Repayments: The following table summarizes long-term debt issuances and repayments:

(Millions of Dollars)Issuance/(Repayment)Issue Date or Repayment DateMaturity DateUse of Proceeds for Issuance/
Repayment Information
Eversource Parent 2.90% Series V Senior Notes
$650.0 February 2022March 2027
Repaid Series K Senior Notes at maturity and short-term debt
Eversource Parent 3.38% Series W Senior Notes
650.0 February 2022March 2032
Repaid Series K Senior Notes at maturity and short-term debt
Eversource Parent 2.75% Series K Senior Notes
(750.0)March 2022March 2022Paid at maturity
Yankee Gas 8.48% Series B First Mortgage Bonds
(20.0)March 2022March 2022Paid at maturity
v3.22.1
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES
 3 Months Ended
Mar. 31, 2022
Rate Reduction Bonds and Variable Interest Entity [Abstract]  
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES
Rate Reduction Bonds: In May 2018, PSNH Funding, a wholly-owned subsidiary of PSNH, issued $635.7 million of securitized RRBs in multiple tranches with a weighted average interest rate of 3.66 percent, and final maturity dates ranging from 2026 to 2035.  The RRBs are expected to be repaid by February 1, 2033. RRB payments consist of principal and interest and are paid semi-annually, beginning on February 1, 2019. The RRBs were issued pursuant to a finance order issued by the NHPUC in January 2018 to recover remaining costs resulting from the divestiture of PSNH’s generation assets.

PSNH Funding was formed solely to issue RRBs to finance PSNH's unrecovered remaining costs associated with the divestiture of its generation assets. PSNH Funding is considered a VIE primarily because the equity capitalization is insufficient to support its operations. PSNH has the power to direct the significant activities of the VIE and is most closely associated with the VIE as compared to other interest holders. Therefore, PSNH is considered the primary beneficiary and consolidates PSNH Funding in its consolidated financial statements.

The following tables summarize the impact of PSNH Funding on PSNH's balance sheets and income statements:
(Millions of Dollars)
PSNH Balance Sheets:As of March 31, 2022As of December 31, 2021
Restricted Cash - Current Portion (included in Current Assets)$16.3 $31.1 
Restricted Cash - Long-Term Portion (included in Other Long-Term Assets)3.2 3.2 
Securitized Stranded Cost (included in Regulatory Assets)468.1 478.9 
Other Regulatory Liabilities (included in Regulatory Liabilities)6.0 5.4 
Accrued Interest (included in Other Current Liabilities)2.9 7.5 
Rate Reduction Bonds - Current Portion43.2 43.2 
Rate Reduction Bonds - Long-Term Portion432.1 453.7 

(Millions of Dollars)
PSNH Income Statements:
For the Three Months Ended
March 31, 2022March 31, 2021
Amortization of RRB Principal (included in Amortization of Regulatory Assets, Net)$10.8 $10.8 
Interest Expense on RRB Principal (included in Interest Expense)4.4 4.7 
v3.22.1
PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION
 3 Months Ended
Mar. 31, 2022
Postemployment Benefits [Abstract]  
PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION
Eversource provides defined benefit retirement plans (Pension Plans) that cover eligible employees.  In addition to the Pension Plans, Eversource maintains non-qualified defined benefit retirement plans (SERP Plans), which provide benefits in excess of Internal Revenue Code limitations to eligible participants consisting of current and retired employees. Eversource also provides defined benefit postretirement plans (PBOP Plans) that provide life insurance and a health reimbursement arrangement created for the purpose of reimbursing retirees and dependents for health insurance premiums and certain medical expenses to eligible employees that meet certain age and service eligibility requirements.

The components of net periodic benefit plan expense/(income) for the Pension, SERP and PBOP Plans, prior to amounts capitalized as Property, Plant and Equipment or deferred as regulatory assets/(liabilities) for future recovery or refund, are shown below.  The service cost component of net periodic benefit plan expense/(income), less the capitalized portion, is included in Operations and Maintenance expense on the statements of income. The remaining components of net periodic benefit plan expense/(income), less the deferred portion, are included in Other Income, Net on the statements of income. Pension, SERP and PBOP expense/(income) reflected in the statements of cash flows for CL&P, NSTAR Electric and PSNH does not include intercompany allocations of net periodic benefit plan expense/(income), as these amounts are cash settled on a short-term basis.

Pension and SERPPBOP
For the Three Months Ended March 31, 2022For the Three Months Ended March 31, 2022
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
Service Cost$17.7 $4.5 $3.6 $1.8 $2.8 $0.5 $0.5 $0.2 
Interest Cost38.6 7.8 8.1 4.2 5.0 0.9 1.3 0.5 
Expected Return on Plan Assets(131.7)(26.6)(32.0)(14.1)(22.4)(2.8)(10.6)(1.6)
Actuarial Losses, net30.7 4.2 8.5 2.2 — — — — 
Prior Service Cost/(Credit)0.4 — 0.1 — (5.4)0.2 (4.3)0.1 
Total Net Periodic Benefit Plan Income$(44.3)$(10.1)$(11.7)$(5.9)$(20.0)$(1.2)$(13.1)$(0.8)
Intercompany Income AllocationsN/A$(3.8)$(2.9)$(0.8)N/A$(0.9)$(0.9)$(0.3)
Pension and SERPPBOP
For the Three Months Ended March 31, 2021For the Three Months Ended March 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
Service Cost$21.3 $6.3 $4.0 $2.2 $3.5 $0.6 $0.6 $0.3 
Interest Cost32.6 7.3 6.7 3.6 4.4 0.8 1.1 0.5 
Expected Return on Plan Assets(108.9)(21.6)(26.9)(11.9)(19.7)(2.6)(9.3)(1.5)
Actuarial Loss61.6 13.0 15.5 4.9 2.6 0.4 0.6 0.3 
Prior Service Cost/(Credit)0.3 — 0.1 — (5.3)0.2 (4.2)0.1 
Total Net Periodic Benefit Plan Expense/(Income)$6.9 $5.0 $(0.6)$(1.2)$(14.5)$(0.6)$(11.2)$(0.3)
Intercompany Expense/(Income) AllocationsN/A$1.3 $1.5 $0.5 N/A$(0.3)$(0.4)$(0.1)
Eversource Contributions: Based on the current status of the Pension Plans and federal pension funding requirements, there is no minimum funding requirement for our Pension Plans for 2022. Eversource currently expects to make contributions between $100 million to $175 million in 2022, most of which will be contributed by Eversource Service, however the planned contribution is discretionary and subject to change. Eversource currently estimates contributing $2.4 million to the PBOP Plans in 2022.
v3.22.1
COMMITMENTS AND CONTINGENCIES
 3 Months Ended
Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]  
COMMITMENTS AND CONTINGENCIES COMMITMENTS AND CONTINGENCIES
A.    Environmental Matters
Eversource, CL&P, NSTAR Electric and PSNH are subject to environmental laws and regulations intended to mitigate or remove the effect of past operations and improve or maintain the quality of the environment. These laws and regulations require the removal or the remedy of the effect on the environment of the disposal or release of certain specified hazardous substances at current and former operating sites. Eversource, CL&P, NSTAR Electric and PSNH have an active environmental auditing and training program and each believes it is substantially in compliance with all enacted laws and regulations.

The number of environmental sites and related reserves for which remediation or long-term monitoring, preliminary site work or site assessment is being performed are as follows:
 As of March 31, 2022As of December 31, 2021
Number of SitesReserve
(in millions)		Number of SitesReserve
(in millions)
Eversource61 $117.8 61 $115.4 
CL&P14 14.3 14 13.9 
NSTAR Electric11 3.2 11 3.3 
PSNH9 6.4 9 6.3 

Included in the number of sites and reserve amounts above are former MGP sites that were operated several decades ago and manufactured natural gas from coal and other processes, which resulted in certain by-products remaining in the environment that may pose a potential risk to human health and the environment, for which Eversource may have potential liability.  The reserve balances related to these former MGP sites were $108.3 million and $105.6 million as of March 31, 2022 and December 31, 2021, respectively, and related primarily to the natural gas business segment.

These reserve estimates are subjective in nature as they take into consideration several different remediation options at each specific site.  The reliability and precision of these estimates can be affected by several factors, including new information concerning either the level of contamination at the site, the extent of Eversource's, CL&P's, NSTAR Electric's and PSNH's responsibility for remediation or the extent of remediation required, recently enacted laws and regulations or changes in cost estimates due to certain economic factors.  It is possible that new information or future developments could require a reassessment of the potential exposure to required environmental remediation.  As this information becomes available, management will continue to assess the potential exposure and adjust the reserves accordingly.

B.    Long-Term Contractual Arrangements
The following is an update to the current status of long-term contractual arrangements set forth in Note 13B of the Eversource 2021 Form 10-K.

Renewable Energy: Renewable energy contracts include non-cancelable commitments under contracts of NSTAR Electric for the purchase of energy and RECs from renewable energy facilities.
NSTAR Electric      
(Millions of Dollars)20222023202420252026ThereafterTotal
Renewable Energy$75.6 $78.3 $269.4 $315.8 $322.1 $5,812.2 $6,873.4 

The table has been updated to include long-term commitments of NSTAR Electric pertaining to the Vineyard Wind LLC contract awarded under the Massachusetts Clean Energy 83C procurement solicitation. NSTAR Electric, along with other Massachusetts distribution companies, entered into 20-year contracts for this 800 megawatt offshore wind project. Construction on the Vineyard Wind project commenced in 2022. Estimated costs under this contract are expected to begin in 2024 and range between $240 million and $375 million per year under NSTAR Electric’s 20-year contract, totaling approximately $6.0 billion.
C.    Guarantees and Indemnifications
In the normal course of business, Eversource parent provides credit assurances on behalf of its subsidiaries, including CL&P, NSTAR Electric and PSNH, in the form of guarantees. Management does not anticipate a material impact to net income or cash flows as a result of these various guarantees and indemnifications. 

Guarantees issued on behalf of unconsolidated entities, including equity method offshore wind investments, for which Eversource parent is the guarantor, are recorded at fair value as a liability on the balance sheet at the inception of the guarantee. Eversource regularly reviews performance risk under these guarantee arrangements, and in the event it becomes probable that Eversource parent will be required to perform under the guarantee, the amount of probable payment will be recorded. The fair value of guarantees issued on behalf of unconsolidated entities are recorded within Other Long-Term Liabilities on the balance sheet, and were $7.0 million and $7.3 million as of March 31, 2022 and December 31, 2021, respectively.

The following table summarizes Eversource parent's exposure to guarantees and indemnifications of its subsidiaries and affiliates to external parties:  
As of March 31, 2022
Company (Obligor)DescriptionMaximum Exposure
(in millions)		Expiration Dates
North East Offshore LLC
Construction-related purchase agreements with third-party contractors (1)
$936.3 
 (1)
Sunrise Wind LLC
Construction-related purchase agreements with third-party contractors (2)
330.6 
2026
Revolution Wind, LLC
Construction-related purchase agreements with third-party contractors (3)
254.7 2024 - 2027
South Fork Wind, LLC
Construction-related purchase agreements with third-party contractors (4)
165.3 2023 - 2026
Eversource Investment LLC
Funding and indemnification obligations of North East Offshore LLC (5)
107.8 
 (5)
South Fork Wind, LLC
Power Purchase Agreement Security (6)
7.1 
 (6)
Sunrise Wind LLC
OREC capacity production (7)
2.2 
 (7)
Bay State Wind LLCReal estate purchase2.5 2022
South Fork Wind, LLC
Transmission interconnection
1.2 —
Eversource Investment LLC
Letters of Credit (8)
4.3 —
Various
Surety bonds (9)
35.0 2022 - 2023
Eversource ServiceLease payments for real estate0.7 2024

(1)    Eversource parent issued guarantees on behalf of its 50 percent-owned affiliate, North East Offshore LLC (NEO), under which Eversource parent agreed to guarantee 50 percent of NEO’s performance of obligations under certain purchase agreements with third-party contactors, in an aggregate amount not to exceed $1.3 billion with an expiration date in 2025. Eversource parent also issued a separate guarantee to Ørsted on behalf of NEO, under which Eversource parent agreed to guarantee 50 percent of NEO’s payment obligations under certain offshore wind project construction-related agreements with Ørsted in an aggregate amount not to exceed $62.5 million and expiring upon full performance of the guaranteed obligation. Any amounts paid under this guarantee to Ørsted will count toward, but not increase, the maximum amount of the Funding Guarantee described in Note 5, below. The guarantee expires upon the full performance of the guaranteed obligations.

(2)     Eversource parent issued a guaranty on behalf of its 50 percent-owned affiliate, Sunrise Wind LLC, whereby Eversource parent will guarantee Sunrise Wind LLC's performance of certain obligations, in an aggregate amount not to exceed $420.6 million, in connection with a construction-related purchase agreement. Eversource parent’s obligations under the guarantee expire upon the earlier of (i) April 2026 and (ii) full performance of the guaranteed obligations.     

(3)    Eversource parent issued guarantees on behalf of its 50 percent-owned affiliate, Revolution Wind, LLC, whereby Eversource parent will guarantee Revolution Wind, LLC's performance of certain obligations, in an aggregate amount not to exceed $268.5 million, in connection with construction-related purchase agreements. Eversource parent’s obligations under the guarantees expire upon the earlier of (i) dates ranging from November 2024 and November 2027 and (ii) full performance of the guaranteed obligations.

(4)    Eversource parent issued guarantees on behalf of its 50 percent-owned affiliate, South Fork Wind, LLC, whereby Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations in connection with construction-related purchase agreements. Under these guarantees, Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations, in a total aggregate amount not to exceed $184.0 million. Eversource parent’s obligations under these guarantees expire upon the earlier of (i) dates ranging from June 2023 and August 2026 and (ii) full performance of the guaranteed obligations.

(5)    Eversource parent issued a guarantee (Funding Guarantee) on behalf of Eversource Investment LLC (EI), its wholly-owned subsidiary that holds a 50 percent ownership interest in NEO, under which Eversource parent agreed to guarantee certain funding obligations and certain indemnification payments of EI under the operating agreement of NEO, in an amount not to exceed $910 million. The guaranteed obligations include payment of EI's funding obligations during the construction phase of NEO’s underlying offshore wind projects and indemnification obligations associated with third party credit support for its investment in NEO. Eversource parent’s obligations under the Funding Guarantee expire upon the full performance of the guaranteed obligations.
(6)    Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, South Fork Wind, LLC, whereby Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations, in an amount not to exceed $7.1 million, under a Power Purchase Agreement between the Long Island Power Authority and South Fork Wind, LLC (the Agreement). The guarantee expires upon the later of (i) the end of the Agreement term and (ii) full performance of the guarantee obligations.

(7)    Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, Sunrise Wind LLC, whereby Eversource parent will guarantee Sunrise Wind LLC's performance of certain obligations, in an amount not to exceed $15.4 million, under the Offshore Wind Renewable Energy Certificate Purchase and Sale Agreement (the Agreement). The Agreement was executed by and between the New York State Energy Research and Development Authority (NYSERDA) and Sunrise Wind LLC. The guarantee expires upon the full performance of the guaranteed obligations.    

(8)    On September 16, 2020, Eversource parent entered into a guarantee on behalf of EI, which holds Eversource's investments in offshore wind-related equity method investments, under which Eversource parent would guarantee EI's obligations under a letter of credit facility with a financial institution that EI may request in an aggregate amount of up to approximately $25 million. In January 2022, Eversource parent issued two letters of credit on behalf of South Fork Wind, LLC related to future decommissioning obligations of certain onshore transmission assets totaling $4.3 million.

(9)    Surety bond expiration dates reflect termination dates, the majority of which will be renewed or extended.  Certain surety bonds contain credit ratings triggers that would require Eversource parent to post collateral in the event that the unsecured debt credit ratings of Eversource parent are downgraded.

Second Quarter 2022 Guarantees: In April 2022, Eversource parent issued three additional guarantees, two on behalf of Revolution Wind, LLC and one on behalf of South Fork Wind, LLC, whereby Eversource parent will guarantee performance of construction-related purchase agreements in an aggregate amount not to exceed $160.2 million.

D.     Spent Nuclear Fuel Obligations - Yankee Companies
CL&P, NSTAR Electric and PSNH have plant closure and fuel storage cost obligations to the Yankee Companies, which have each completed the physical decommissioning of their respective nuclear power facilities and are now engaged in the long-term storage of their spent fuel. The Yankee Companies fund these costs through litigation proceeds received from the DOE and, to the extent necessary, through wholesale, FERC-approved rates charged under power purchase agreements with several New England utilities, including CL&P, NSTAR Electric and PSNH. CL&P, NSTAR Electric and PSNH, in turn recover these costs from their customers through state regulatory commission-approved retail rates. The Yankee Companies collect amounts that management believes are adequate to recover the remaining plant closure and fuel storage cost estimates for the respective plants. Management believes CL&P and NSTAR Electric will recover their shares of these obligations from their customers. PSNH has recovered its total share of these costs from its customers.

Spent Nuclear Fuel Litigation:
The Yankee Companies have filed complaints against the DOE in the Court of Federal Claims seeking monetary damages resulting from the DOE's failure to accept delivery of, and provide for a permanent facility to store, spent nuclear fuel pursuant to the terms of the 1983 spent fuel and high-level waste disposal contracts between the Yankee Companies and the DOE. The court previously awarded the Yankee Companies damages for Phases I, II, III and IV of litigation resulting from the DOE's failure to meet its contractual obligations. These Phases covered damages incurred in the years 1998 through 2016, and the awarded damages have been received by the Yankee Companies with certain amounts of the damages refunded to their customers.

DOE Phase V Damages - On March 25, 2021, each of the Yankee Companies filed a fifth set of lawsuits against the DOE in the Court of Federal Claims. The Yankee Companies filed claims seeking monetary damages totaling $120.4 million for CYAPC, YAEC and MYAPC, resulting from the DOE's failure to begin accepting spent nuclear fuel for disposal covering the years from 2017 to 2020 (DOE Phase V). The DOE Phase V trial is expected to begin in the third quarter of 2023.

E.    FERC ROE Complaints
Four separate complaints were filed at the FERC by combinations of New England state attorneys general, state regulatory commissions, consumer advocates, consumer groups, municipal parties and other parties (collectively, the Complainants). In each of the first three complaints, filed on October 1, 2011, December 27, 2012, and July 31, 2014, respectively, the Complainants challenged the NETOs' base ROE of 11.14 percent that had been utilized since 2005 and sought an order to reduce it prospectively from the date of the final FERC order and for the separate 15-month complaint periods. In the fourth complaint, filed April 29, 2016, the Complainants challenged the NETOs' base ROE billed of 10.57 percent and the maximum ROE for transmission incentive (incentive cap) of 11.74 percent, asserting that these ROEs were unjust and unreasonable.

The ROE originally billed during the period October 1, 2011 (beginning of the first complaint period) through October 15, 2014 consisted of a base ROE of 11.14 percent and incentives up to 13.1 percent. On October 16, 2014, the FERC set the base ROE at 10.57 percent and the incentive cap at 11.74 percent for the first complaint period. This was also effective for all prospective billings to customers beginning October 16, 2014. This FERC order was vacated on April 14, 2017 by the U.S. Court of Appeals for the D.C. Circuit (the Court).

All amounts associated with the first complaint period have been refunded, which totaled $38.9 million (pre-tax and excluding interest) at Eversource and reflected both the base ROE and incentive cap prescribed by the FERC order. The refund consisted of $22.4 million for CL&P, $13.7 million for NSTAR Electric and $2.8 million for PSNH.
Eversource has recorded a reserve of $39.1 million (pre-tax and excluding interest) for the second complaint period as of both March 31, 2022 and December 31, 2021. This reserve represents the difference between the billed rates during the second complaint period and a 10.57 percent base ROE and 11.74 percent incentive cap. The reserve consisted of $21.4 million for CL&P, $14.6 million for NSTAR Electric and $3.1 million for PSNH as of both March 31, 2022 and December 31, 2021.

On October 16, 2018, FERC issued an order on all four complaints describing how it intends to address the issues that were remanded by the Court. FERC proposed a new framework to determine (1) whether an existing ROE is unjust and unreasonable and, if so, (2) how to calculate a replacement ROE. Initial briefs were filed by the NETOs, Complainants and FERC Trial Staff on January 11, 2019 and reply briefs were filed on March 8, 2019. The NETOs' brief was supportive of the overall ROE methodology determined in the October 16, 2018 order provided the FERC does not change the proposed methodology or alter its implementation in a manner that has a material impact on the results.

The FERC order included illustrative calculations for the first complaint using FERC's proposed frameworks with financial data from that complaint. Those illustrative calculations indicated that for the first complaint period, for the NETOs, which FERC concludes are of average financial risk, the preliminary just and reasonable base ROE is 10.41 percent and the preliminary incentive cap on total ROE is 13.08 percent.

If the results of the illustrative calculations were included in a final FERC order for each of the complaint periods, then a 10.41 percent base ROE and a 13.08 percent incentive cap would not have a significant impact on our financial statements for all of the complaint periods. These preliminary calculations are not binding and do not represent what we believe to be the most likely outcome of a final FERC order.

On November 21, 2019, FERC issued Opinion No. 569 affecting the two pending transmission ROE complaints against the Midcontinent ISO (MISO) transmission owners, in which FERC adopted a new methodology for determining base ROEs. Various parties sought rehearing. On December 23, 2019, the NETOs filed supplementary materials in the NETOs' four pending cases to respond to this new methodology because of the uncertainty of the applicability to the NETOs' cases.

On May 21, 2020, the FERC issued its order in Opinion No. 569-A on the rehearing of the MISO transmission owners' cases, in which FERC again changed its methodology for determining the MISO transmission owners' base ROEs. On November 19, 2020, the FERC issued Opinion No. 569-B denying rehearing of Opinion No. 569-A and reaffirmed the methodology previously adopted in Opinion No. 569-A. The new methodology differs significantly from the methodology proposed by FERC in its October 16, 2018 order to determine the NETOs' base ROEs in its four pending cases. FERC Opinion Nos. 569-A and 569-B are currently under appeal with the Court.

Given the significant uncertainty regarding the applicability of the FERC opinions in the MISO transmission owners' two complaint cases to the NETOs' pending four complaint cases, Eversource concluded that there is no reasonable basis for a change to the reserve or recognized ROEs for any of the complaint periods at this time. As well, Eversource cannot reasonably estimate a range of loss for any of the four complaint proceedings at this time.

Eversource, CL&P, NSTAR Electric and PSNH currently record revenues at the 10.57 percent base ROE and incentive cap at 11.74 percent established in the October 16, 2014 FERC order.

A change of 10 basis points to the base ROE used to establish the reserves would impact Eversource's after-tax earnings by an average of approximately $3 million for each of the four 15-month complaint periods.

F.    Eversource and NSTAR Electric Boston Harbor Civil Action
In 2016, the United States Attorney on behalf of the United States Army Corps of Engineers filed a civil action in the United States District Court for the District of Massachusetts against NSTAR Electric, HEEC, and the Massachusetts Water Resources Authority (together with NSTAR Electric and HEEC, the "Defendants").  The action alleged that the Defendants failed to comply with certain permitting requirements related to the placement of the HEEC-owned electric distribution cable beneath Boston Harbor.

The parties reached a settlement pursuant to which HEEC agreed to install a new 115kV distribution cable across Boston Harbor to Deer Island, utilizing a different route, and remove portions of the existing cable. Construction of the new distribution cable was completed in August 2019, and removal of the portions of the existing cable was completed in January 2020. All issues surrounding the current permit from the United States Army Corps of Engineers are expected to be resolved and remaining restoration efforts completed, at which time such litigation is expected to be dismissed with prejudice.

G.    CL&P Regulatory Matters
CL&P Tropical Storm Isaias Response Investigation: In August 2020, PURA opened a docket to investigate the preparation for and response to Tropical Storm Isaias by Connecticut utilities, including CL&P. On April 28, 2021, PURA issued a final decision on CL&P’s compliance with its emergency response plan that concluded CL&P failed to comply with certain storm performance standards and was imprudent in certain instances. Specifically, PURA concluded that CL&P did not satisfy the performance standards for managing its municipal liaison program, timely removing electrical hazards from blocked roads, communicating critical information to its customers, or meeting its obligation to secure adequate external contractor and mutual aid resources in a timely manner. Based on its findings, PURA ordered CL&P to adjust its future rates in a pending or future rate proceeding to reflect a monetary penalty in the form of a downward adjustment of 90 basis points in its allowed rate of return on equity (ROE), which is currently 9.25 percent. In its decision, PURA explained that additional monetary penalties and further enforcement orders pursuant to Connecticut statute would be considered in a separate proceeding that was initiated on May 6, 2021.
On May 6, 2021, as part of the penalty proceeding, PURA issued a notice of violation that included an assessment of $30 million, consisting of a $28.4 million civil penalty for non-compliance with storm performance standards to be provided as credits on customer bills and a $1.6 million fine for violations of accident reporting requirements to be paid to the State of Connecticut’s general fund. On July 14, 2021, PURA issued a final decision in this penalty proceeding that included an assessment of $28.6 million, maintaining the $28.4 million performance penalty and reducing the $1.6 million fine for accident reporting to $0.2 million. The $28.4 million performance penalty is currently being credited to customers on electric bills beginning on September 1, 2021 over a one-year period. The $28.4 million is the maximum statutory penalty amount under applicable Connecticut law in effect at the time of Tropical Storm Isaias, which is 2.5 percent of CL&P’s annual distribution revenues. In the first quarter of 2021, the liability for the performance penalty of $30 million was recorded as a current regulatory liability on CL&P’s balance sheet and as a charge to Operations and Maintenance expense on the income statement. The after-tax earnings impact of this charge was $0.07 per share. The penalty was subsequently reclassified from Operations and Maintenance expense to a reduction of Operating Revenues in the third quarter of 2021 in connection with the finalization of an October 1, 2021 settlement agreement that was approved by PURA on October 27, 2021.
v3.22.1
FAIR VALUE OF FINANCIAL INSTRUMENTS
 3 Months Ended
Mar. 31, 2022
Fair Value Disclosures [Abstract]  
FAIR VALUE OF FINANCIAL INSTRUMENTS FAIR VALUE OF FINANCIAL INSTRUMENTS
The following methods and assumptions were used to estimate the fair value of each of the following financial instruments:

Preferred Stock, Long-Term Debt and Rate Reduction Bonds:  The fair value of CL&P's and NSTAR Electric's preferred stock is based upon pricing models that incorporate interest rates and other market factors, valuations or trades of similar securities and cash flow projections.  The fair value of long-term debt and RRB debt securities is based upon pricing models that incorporate quoted market prices for those issues or similar issues adjusted for market conditions, credit ratings of the respective companies and treasury benchmark yields.  The fair values provided in the table below are classified as Level 2 within the fair value hierarchy.  Carrying amounts and estimated fair values are as follows:
 EversourceCL&PNSTAR ElectricPSNH
(Millions of Dollars)Carrying
Amount		Fair
Value		Carrying
Amount		Fair
Value		Carrying
Amount		Fair
Value		Carrying
Amount		Fair
Value
As of March 31, 2022:        
Preferred Stock Not Subject to Mandatory Redemption
$155.6 $158.3 $116.2 $115.5 $43.0 $42.8 $— $— 
Long-Term Debt18,729.6 18,562.3 4,215.7 4,392.2 3,986.3 4,094.1 1,164.0 1,086.3 
Rate Reduction Bonds475.3 492.8 — — — — 475.3 492.8 
As of December 31, 2021:        
Preferred Stock Not Subject to Mandatory Redemption
$155.6 $166.3 $116.2 $122.3 $43.0 $44.0 $— $— 
Long-Term Debt18,216.7 19,636.3 4,215.4 4,848.9 3,985.4 4,453.5 1,163.8 1,220.6 
Rate Reduction Bonds496.9 543.3 — — — — 496.9 543.3 

Derivative Instruments and Marketable Securities: Derivative instruments and investments in marketable securities are carried at fair value.  For further information, see Note 4, "Derivative Instruments," and Note 5, "Marketable Securities," to the financial statements.  

See Note 1C, "Summary of Significant Accounting Policies – Fair Value Measurements," for the fair value measurement policy and the fair value hierarchy.
v3.22.1
ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS)
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS)
The changes in accumulated other comprehensive income/(loss) by component, net of tax, are as follows:
For the Three Months Ended March 31, 2022For the Three Months Ended March 31, 2021
Eversource
(Millions of Dollars)
Qualified
Cash Flow
Hedging
Instruments		Unrealized
Gains/(Losses) on Marketable
Securities		Defined
Benefit Plans		TotalQualified
Cash Flow
Hedging
Instruments		Unrealized
Gains/(Losses) on Marketable
Securities		Defined
Benefit Plans		Total
Balance as of Beginning of Period$(0.4)$0.4 $(42.3)$(42.3)$(1.4)$1.1 $(76.1)$(76.4)
OCI Before Reclassifications
— (0.8)— (0.8)— (0.7)— (0.7)
Amounts Reclassified from AOCI
— — 1.5 1.5 0.4 — 1.5 1.9 
Net OCI— (0.8)1.5 0.7 0.4 (0.7)1.5 1.2 
Balance as of End of Period$(0.4)$(0.4)$(40.8)$(41.6)$(1.0)$0.4 $(74.6)$(75.2)

Defined benefit plan OCI amounts before reclassifications relate to actuarial gains and losses that arose during the year and were recognized in AOCI. The unamortized actuarial gains and losses and prior service costs on the defined benefit plans are amortized from AOCI into Other Income, Net over the average future employee service period, and are reflected in amounts reclassified from AOCI.
v3.22.1
COMMON SHARES
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
COMMON SHARES COMMON SHARES
The following table sets forth the Eversource parent common shares and the shares of common stock of CL&P, NSTAR Electric and PSNH that were authorized and issued, as well as the respective per share par values:  
 Shares
 Authorized as of March 31, 2022 and December 31, 2021Issued as of
 Par ValueMarch 31, 2022December 31, 2021
Eversource$5 380,000,000 357,818,402 357,818,402 
CL&P$10 24,500,000 6,035,205 6,035,205 
NSTAR Electric$1 100,000,000 200 200 
PSNH$1 100,000,000 301 301 

Treasury Shares: As of March 31, 2022 and December 31, 2021, there were 12,968,130 and 13,415,206 Eversource common shares held as treasury shares, respectively. As of March 31, 2022 and December 31, 2021, there were 344,850,272 and 344,403,196 Eversource common shares outstanding, respectively.
Eversource issues treasury shares to satisfy awards under the Company's incentive plans, shares issued under the dividend reinvestment and share purchase plan, and matching contributions under the Eversource 401k Plan. Eversource also issued treasury shares for its 2021 water business acquisition. The issuance of treasury shares represents a non-cash transaction, as the treasury shares were used to fulfill Eversource's obligations that require the issuance of common shares.COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTSDividends on the preferred stock of CL&P and NSTAR Electric totaled $1.9 million for each of the three months ended March 31, 2022 and 2021. These dividends were presented as Net Income Attributable to Noncontrolling Interests on the Eversource statements of income. Noncontrolling Interest – Preferred Stock of Subsidiaries on the Eversource balance sheets totaled $155.6 million as of March 31, 2022 and December 31, 2021. On the Eversource balance sheets, Common Shareholders' Equity was fully attributable to Eversource parent and Noncontrolling Interest – Preferred Stock of Subsidiaries was fully attributable to the noncontrolling interest.
v3.22.1
COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS COMMON SHARES
The following table sets forth the Eversource parent common shares and the shares of common stock of CL&P, NSTAR Electric and PSNH that were authorized and issued, as well as the respective per share par values:  
 Shares
 Authorized as of March 31, 2022 and December 31, 2021Issued as of
 Par ValueMarch 31, 2022December 31, 2021
Eversource$5 380,000,000 357,818,402 357,818,402 
CL&P$10 24,500,000 6,035,205 6,035,205 
NSTAR Electric$1 100,000,000 200 200 
PSNH$1 100,000,000 301 301 

Treasury Shares: As of March 31, 2022 and December 31, 2021, there were 12,968,130 and 13,415,206 Eversource common shares held as treasury shares, respectively. As of March 31, 2022 and December 31, 2021, there were 344,850,272 and 344,403,196 Eversource common shares outstanding, respectively.
Eversource issues treasury shares to satisfy awards under the Company's incentive plans, shares issued under the dividend reinvestment and share purchase plan, and matching contributions under the Eversource 401k Plan. Eversource also issued treasury shares for its 2021 water business acquisition. The issuance of treasury shares represents a non-cash transaction, as the treasury shares were used to fulfill Eversource's obligations that require the issuance of common shares.COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTSDividends on the preferred stock of CL&P and NSTAR Electric totaled $1.9 million for each of the three months ended March 31, 2022 and 2021. These dividends were presented as Net Income Attributable to Noncontrolling Interests on the Eversource statements of income. Noncontrolling Interest – Preferred Stock of Subsidiaries on the Eversource balance sheets totaled $155.6 million as of March 31, 2022 and December 31, 2021. On the Eversource balance sheets, Common Shareholders' Equity was fully attributable to Eversource parent and Noncontrolling Interest – Preferred Stock of Subsidiaries was fully attributable to the noncontrolling interest.
v3.22.1
EARNINGS PER SHARE
 3 Months Ended
Mar. 31, 2022
Earnings Per Share [Abstract]  
EARNINGS PER SHARE EARNINGS PER SHARE
Basic EPS is computed based upon the weighted average number of common shares outstanding during each period.  Diluted EPS is computed on the basis of the weighted average number of common shares outstanding plus the potential dilutive effect of certain share-based compensation awards as if they were converted into outstanding common shares.  The dilutive effect of unvested RSU and performance share awards is calculated using the treasury stock method.  RSU and performance share awards are included in basic weighted average common shares outstanding as of the date that all necessary vesting conditions have been satisfied. For the three months ended March 31, 2022 and 2021, there were no antidilutive share awards excluded from the computation of diluted EPS.

The following table sets forth the components of basic and diluted EPS:
Eversource
(Millions of Dollars, except share information)
For the Three Months Ended
March 31, 2022March 31, 2021
Net Income Attributable to Common Shareholders$443.4 $366.1 
Weighted Average Common Shares Outstanding:  
Basic345,156,346 343,678,243 
Dilutive Effect504,787 656,446 
Diluted345,661,133 344,334,689 
Basic EPS$1.28 $1.07 
Diluted EPS$1.28 $1.06 
v3.22.1
REVENUES
 3 Months Ended
Mar. 31, 2022
Revenue from Contract with Customer [Abstract]  
REVENUES REVENUES
The following tables present operating revenues disaggregated by revenue source:
For the Three Months Ended March 31, 2022
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
Revenues from Contracts with Customers
Retail Tariff Sales
Residential $1,186.2 $556.8 $— $28.2 $— $— $1,771.2 
Commercial 661.3 257.6 — 14.6 — (1.1)932.4 
Industrial89.6 68.1 — 1.1 — (4.5)154.3 
Total Retail Tariff Sales Revenues1,937.1 882.5 — 43.9 — (5.6)2,857.9 
Wholesale Transmission Revenues— — 446.2 — 24.4 (364.7)105.9 
Wholesale Market Sales Revenues365.5 33.5 — 0.8 — — 399.8 
Other Revenues from Contracts with Customers17.7 1.0 3.8 1.9 359.1 (353.1)30.4 
Amortization of/(Reserve for)
    Revenues Subject to Refund (1)
58.4 — — (0.4)— — 58.0 
Total Revenues from Contracts with Customers2,378.7 917.0 450.0 46.2 383.5 (723.4)3,452.0 
Alternative Revenue Programs4.8 10.2 (15.0)2.2 — 13.6 15.8 
Other Revenues (2)
2.8 0.4 0.2 0.1 — — 3.5 
Total Operating Revenues$2,386.3 $927.6 $435.2 $48.5 $383.5 $(709.8)$3,471.3 
For the Three Months Ended March 31, 2021
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
Revenues from Contracts with Customers
Retail Tariff Sales
Residential $1,066.0 $466.3 $— $27.7 $— $— $1,560.0 
Commercial 559.9 207.6 — 13.8 — (1.4)779.9 
Industrial83.0 55.9 — 1.0 — (3.5)136.4 
Total Retail Tariff Sales Revenues1,708.9 729.8 — 42.5 — (4.9)2,476.3 
Wholesale Transmission Revenues— — 394.3 — 19.2 (321.0)92.5 
Wholesale Market Sales Revenues149.1 26.4 — 0.8 — — 176.3 
Other Revenues from Contracts with Customers18.2 1.3 3.4 1.2 323.8 (321.3)26.6 
Total Revenues from Contracts with Customers1,876.2 757.5 397.7 44.5 343.0 (647.2)2,771.7 
Alternative Revenue Programs23.0 22.8 2.7 1.8 — 2.2 52.5 
Other Revenues (2)
1.1 0.2 0.2 0.1 — — 1.6 
Total Operating Revenues$1,900.3 $780.5 $400.6 $46.4 $343.0 $(645.0)$2,825.8 
For the Three Months Ended March 31, 2022For the Three Months Ended March 31, 2021
(Millions of Dollars)CL&PNSTAR ElectricPSNHCL&PNSTAR ElectricPSNH
Revenues from Contracts with Customers
Retail Tariff Sales
Residential $599.1 $404.6 $182.5 $545.8 $362.4 $157.8 
Commercial 242.2 331.3 88.4 214.2 268.3 77.8 
Industrial33.5 34.1 22.0 36.7 24.6 21.7 
Total Retail Tariff Sales Revenues874.8 770.0 292.9 796.7 655.3 257.3 
Wholesale Transmission Revenues209.1 165.2 71.9 189.0 147.1 58.2 
Wholesale Market Sales Revenues279.9 57.9 27.7 109.7 24.4 15.0 
Other Revenues from Contracts with Customers7.9 11.6 2.6 7.3 11.7 3.2 
Amortization of Revenues Subject to Refund (1)
58.4 — — — — — 
Total Revenues from Contracts with Customers1,430.1 1,004.7 395.1 1,102.7 838.5 333.7 
Alternative Revenue Programs1.3 (8.2)(3.3)8.9 13.8 3.0 
Other Revenues (2)
0.1 2.0 0.9 0.2 1.1 — 
Eliminations(145.7)(135.3)(53.3)(124.5)(116.4)(43.3)
Total Operating Revenues$1,285.8 $863.2 $339.4 $987.3 $737.0 $293.4 
(1)    Amortization of Revenues Subject to Refund within the Electric Distribution segment in the first quarter of 2022 represents customer credits being distributed to CL&P’s customers on retail electric bills as a result of the October 2021 CL&P settlement agreement and the 2021 civil penalty for non-compliance with storm performance standards. Total customer credits as a result of the 2021 settlement and civil penalty were $93.4 million. The settlement amount of $65 million was refunded over a two-month billing period from December 1, 2021 to January 31, 2022 and the civil penalty of $28.4 million is being refunded over a one year billing period, which began September 1, 2021. (2)    Other Revenues include certain fees charged to customers that are not considered revenue from contracts with customers. Other Revenues also include lease revenues under lessor accounting guidance of $1.0 million (including $0.2 million at CL&P and $0.6 million at NSTAR Electric) and $1.6 million (including $0.2 million at CL&P and $1.1 million at NSTAR Electric) for the three months ended March 31, 2022 and 2021, respectively.
v3.22.1
SEGMENT INFORMATION
 3 Months Ended
Mar. 31, 2022
Segment Reporting [Abstract]  
SEGMENT INFORMATION SEGMENT INFORMATION
Eversource is organized into the Electric Distribution, Electric Transmission, Natural Gas Distribution and Water Distribution reportable segments and Other based on a combination of factors, including the characteristics of each segments' services, the sources of operating revenues and expenses and the regulatory environment in which each segment operates.  These reportable segments represent substantially all of Eversource's total consolidated revenues.  Revenues from the sale of electricity, natural gas and water primarily are derived from residential, commercial and industrial customers and are not dependent on any single customer.  The Electric Distribution reportable segment includes the results of NSTAR Electric's solar power facilities. Eversource's reportable segments are determined based upon the level at which Eversource's chief operating decision maker assesses performance and makes decisions about the allocation of company resources.
 
The remainder of Eversource's operations is presented as Other in the tables below and primarily consists of 1) the equity in earnings of Eversource parent from its subsidiaries and intercompany interest income, both of which are eliminated in consolidation, and interest expense related to the debt of Eversource parent, 2) the revenues and expenses of Eversource Service, most of which are eliminated in consolidation, 3) the operations of CYAPC and YAEC, 4) the results of other unregulated subsidiaries, which are not part of its core business, and 5) Eversource parent's equity ownership interests that are not consolidated, which primarily include the offshore wind business, a natural gas pipeline owned by Enbridge, Inc., and a renewable energy investment fund.

In the ordinary course of business, Yankee Gas, NSTAR Gas and EGMA purchase natural gas transmission services from the Enbridge, Inc. natural gas pipeline project described above. These affiliate transaction costs total $77.7 million annually and are classified as Purchased Power, Fuel and Transmission on the Eversource statements of income.

Each of Eversource's subsidiaries, including CL&P, NSTAR Electric and PSNH, has one reportable segment.

Cash flows used for investments in plant included in the segment information below are cash capital expenditures that do not include amounts incurred but not paid, cost of removal, AFUDC related to equity funds, and the capitalized portions of pension and PBOP expense.   

Eversource's segment information is as follows:
For the Three Months Ended March 31, 2022
Eversource
(Millions of Dollars)
Electric DistributionNatural Gas DistributionElectric TransmissionWater DistributionOtherEliminationsTotal
Operating Revenues$2,386.3 $927.6 $435.2 $48.5 $383.5 $(709.8)$3,471.3 
Depreciation and Amortization(351.6)(51.9)(81.9)(12.3)(30.2)1.6 (526.3)
Other Operating Expenses(1,845.6)(657.3)(129.3)(27.1)(331.4)708.8 (2,281.9)
Operating Income$189.1 $218.4 $224.0 $9.1 $21.9 $0.6 $663.1 
Interest Expense$(59.4)$(15.8)$(33.2)$(8.2)$(46.8)$10.1 $(153.3)
Other Income, Net47.6 10.1 8.9 2.2 495.9 (493.1)71.6 
Net Income Attributable to Common Shareholders140.9 164.0 148.5 3.7 468.7 (482.4)443.4 
Cash Flows Used for Investments in Plant280.5 127.3 266.9 27.8 62.1 — 764.6 
For the Three Months Ended March 31, 2021
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
Operating Revenues$1,900.3 $780.5 $400.6 $46.4 $343.0 $(645.0)$2,825.8 
Depreciation and Amortization(221.9)(45.7)(73.5)(11.3)(27.3)1.0 (378.7)
Other Operating Expenses(1,530.5)(535.8)(115.4)(25.1)(299.5)644.8 (1,861.5)
Operating Income$147.9 $199.0 $211.7 $10.0 $16.2 $0.8 $585.6 
Interest Expense$(53.3)$(13.9)$(32.7)$(7.9)$(41.6)$11.6 $(137.8)
Other Income, Net20.7 3.9 5.5 1.0 424.1 (421.0)34.2 
Net Income Attributable to Common Shareholders93.2 147.6 135.4 3.6 394.9 (408.6)366.1 
Cash Flows Used for Investments in Plant256.6 131.8 225.2 27.6 47.8 — 689.0 
The following table summarizes Eversource's segmented total assets:
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
As of March 31, 2022$25,883.2 $7,329.7 $12,757.8 $2,572.1 $23,394.3 $(22,647.9)$49,289.2 
As of December 31, 202125,411.2 7,215.9 12,377.8 2,551.1 22,674.7 (21,738.6)48,492.1 
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
 3 Months Ended
Mar. 31, 2022
Accounting Policies [Abstract]  
Basis of Presentation Basis of Presentation
Eversource Energy is a public utility holding company primarily engaged, through its wholly-owned regulated utility subsidiaries, in the energy delivery business.  Eversource Energy's wholly-owned regulated utility subsidiaries consist of CL&P, NSTAR Electric and PSNH (electric utilities), Yankee Gas, NSTAR Gas and Eversource Gas Company of Massachusetts (EGMA) (natural gas utilities) and Aquarion (water utilities). Eversource provides energy delivery and/or water service to approximately 4.4 million electric, natural gas and water customers through ten regulated utilities in Connecticut, Massachusetts and New Hampshire.

The unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH include the accounts of each of their respective subsidiaries.  Intercompany transactions have been eliminated in consolidation.  The accompanying unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH and the unaudited condensed financial statements of CL&P are herein collectively referred to as the "financial statements."

The combined notes to the financial statements have been prepared pursuant to the rules and regulations of the SEC.  Certain information and footnote disclosures included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to such rules and regulations.  The accompanying financial statements should be read in conjunction with the Combined Notes to Financial Statements included in Item 8, "Financial Statements and Supplementary Data," of the Eversource 2021 Form 10-K, which was filed with the SEC on February 17, 2022. The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.  Actual results could differ from those estimates.

The financial statements contain, in the opinion of management, all adjustments (including normal, recurring adjustments) necessary to present fairly Eversource's, CL&P's, NSTAR Electric's and PSNH's financial position as of March 31, 2022 and December 31, 2021, and the results of operations, comprehensive income, common shareholders' equity and cash flows for the three months ended March 31, 2022 and 2021. The results of operations, comprehensive income and cash flows for the three months ended March 31, 2022 and 2021 are not necessarily indicative of the results expected for a full year.  

CYAPC and YAEC are inactive regional nuclear power companies engaged in the long-term storage of their spent nuclear fuel. Eversource consolidates the operations of CYAPC and YAEC because CL&P's, NSTAR Electric's and PSNH's combined ownership and voting interests in each of these entities is greater than 50 percent.  Intercompany transactions between CL&P, NSTAR Electric, PSNH and the CYAPC and YAEC companies have been eliminated in consolidation of the Eversource financial statements.

Eversource holds several equity ownership interests that are not consolidated and are accounted for under the equity method.

Eversource's utility subsidiaries' electric, natural gas and water distribution and transmission businesses are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for entities with rate-regulated operations, which considers the effect of regulation on the differences in the timing of the recognition of certain revenues and expenses from those of other businesses and industries. See Note 2, "Regulatory Accounting," for further information.

Certain reclassifications of prior period data were made in the accompanying financial statements to conform to the current period presentation.

On May 4, 2022, Eversource announced that it had initiated a strategic review of its offshore wind investment portfolio. As part of that review, Eversource will explore strategic alternatives that could result in a potential sale of all, or part, of its 50 percent interest in its offshore wind partnership with Ørsted. Eversource expects to complete this review during 2022. Eversource’s offshore wind business includes a 50 percent ownership interest in North East Offshore, which holds PPAs and contracts for the Revolution Wind, South Fork Wind and Sunrise Wind projects, as well as undeveloped offshore lease area. As of March 31, 2022 and December 31, 2021, Eversource's total equity investment balance in its offshore wind business was $1.33 billion and $1.21 billion, respectively. Eversource’s initiation of the strategic review of its offshore wind investment does not impact the March 31, 2022 financial statements, and at this time, Eversource cannot predict the ultimate outcome or estimate the potential impact of such review.
Allowance for Uncollectible Accounts Allowance for Uncollectible Accounts
Receivables, Net on the balance sheets primarily includes trade receivables from retail customers and customers related to wholesale transmission contracts, wholesale market sales, sales of RECs, and property rentals. Receivables, Net also includes customer receivables for the purchase of electricity from a competitive third party supplier, the current portion of customer energy efficiency loans, property damage receivables and other miscellaneous receivables. There is no material concentration of receivables. Receivables are recorded at amortized cost, net of a credit loss provision (or allowance for uncollectible accounts).

Receivables are presented net of expected credit losses at estimated net realizable value by maintaining an allowance for uncollectible accounts. The current expected credit loss (CECL) model is applied to receivables for purposes of calculating the allowance for uncollectible accounts. This model is based on expected losses and results in the recognition of estimated expected credit losses, including uncollectible amounts for both billed and unbilled revenues, over the life of the receivable at the time a receivable is recorded.

The allowance for uncollectible accounts is determined based upon a variety of judgments and factors, including an aging-based quantitative assessment that applies an estimated uncollectible percentage to each receivable aging category.  Factors in determining credit loss include historical collection, write-off experience, analysis of delinquency statistics, and management's assessment of collectability from customers, including current conditions, customer payment trends, the impact on customer bills because of energy usage trends and changes in rates, flexible payment plans and financial hardship arrearage management programs being offered to customers, reasonable forecasts, and expectations of future collectability and collection efforts. Management continuously assesses the collectability of receivables and adjusts estimates based on actual experience and future expectations based on economic conditions, collection efforts and other factors.  Management also monitors the aging analysis of receivables to determine if there are changes in the collections of accounts receivable. Receivable balances are written off against the allowance for uncollectible accounts when the customer accounts are no longer in service and these balances are deemed to be uncollectible. Management concluded that the reserve balance as of March 31, 2022 adequately reflected the collection risk and net realizable value for its receivables.

As of March 31, 2022 and December 31, 2021, the total amount incurred as a result of COVID-19 included in the allowance for uncollectible accounts was $58.5 million and $55.3 million at Eversource, $20.4 million and $23.9 million at CL&P, and $9.0 million and $9.0 million at NSTAR Electric, respectively. At our Connecticut and Massachusetts utilities, the COVID-19 related uncollectible amounts were deferred either as incremental regulatory costs or deferred through existing regulatory tracking mechanisms that recover uncollectible energy supply costs, as management believes it is probable that these costs will ultimately be recovered from customers in future rates. No COVID-19 related uncollectible amounts were deferred at PSNH as a result of a July 2021 NHPUC order. Based on the status of our COVID-19 regulatory dockets, and policies and practices in the jurisdictions in which we operate, we believe our state regulatory commissions in Connecticut and Massachusetts will allow us to recover our incremental uncollectible customer receivable costs associated with COVID-19.

The PURA allows CL&P and Yankee Gas to accelerate the recovery of accounts receivable balances attributable to qualified customers under financial or medical duress (uncollectible hardship accounts receivable) outstanding for greater than 180 days and 90 days, respectively.  The DPU allows NSTAR Electric, NSTAR Gas and EGMA to recover in rates amounts associated with certain uncollectible hardship accounts receivable. These uncollectible hardship customer account balances are included in Regulatory Assets or Other Long-Term Assets on the balance sheets. Hardship customers are protected from shut-off in certain circumstances, and historical collection experience has reflected a higher default risk as compared to the rest of the receivable population. Management uses a higher credit risk profile for this pool of trade receivables as compared to non-hardship receivables. The allowance for uncollectible hardship accounts is included in the total uncollectible allowance balance.
The total allowance for uncollectible accounts is included in Receivables, Net on the balance sheets.
Fair Value Measurements Fair Value Measurements
Fair value measurement guidance is applied to derivative contracts that are not elected or designated as "normal purchases" or "normal sales" (normal) and to the marketable securities held in trusts.  Fair value measurement guidance is also applied to valuations of the investments used to calculate the funded status of pension and PBOP plans, the nonrecurring fair value measurements of nonfinancial assets such as goodwill, long-lived assets, equity method investments, AROs, and in the valuation of acquisitions. The fair value measurement guidance was also applied in estimating the fair value of preferred stock, long-term debt and RRBs.

Fair Value Hierarchy:  In measuring fair value, Eversource uses observable market data when available in order to minimize the use of unobservable inputs.  Inputs used in fair value measurements are categorized into three fair value hierarchy levels for disclosure purposes.  The entire fair value measurement is categorized based on the lowest level of input that is significant to the fair value measurement.  Eversource evaluates the classification of assets and liabilities measured at fair value on a quarterly basis. The levels of the fair value hierarchy are described below:

Level 1 - Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities as of the reporting date.  Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.  

Level 2 - Inputs are quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs are observable.

Level 3 - Quoted market prices are not available.  Fair value is derived from valuation techniques in which one or more significant inputs or assumptions are unobservable.  Where possible, valuation techniques incorporate observable market inputs that can be validated to external sources such as industry exchanges, including prices of energy and energy-related products.  

Uncategorized - Investments that are measured at net asset value are not categorized within the fair value hierarchy.
Other Taxes Other TaxesEversource's companies that serve customers in Connecticut collect gross receipts taxes levied by the state of Connecticut from their customers. These gross receipts taxes are recorded separately with collections in Operating Revenues and with payments in Taxes Other Than Income Taxes on the statements of incomeAs agents for state and local governments, Eversource's companies that serve customers in Connecticut and Massachusetts collect certain sales taxes that are recorded on a net basis with no impact on the statements of income.
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)
 3 Months Ended
Mar. 31, 2022
Accounting Policies [Abstract]  
Allowance for Uncollectible Accounts The activity in the allowance for uncollectible accounts by portfolio segment as of March 31st is as follows:
EversourceCL&PNSTAR ElectricPSNH
(Millions of Dollars)Hardship AccountsRetail (Non-Hardship),
Wholesale, and Other		Total AllowanceHardship AccountsRetail (Non-Hardship),
Wholesale, and Other		Total AllowanceHardship AccountsRetail (Non-Hardship),
Wholesale, and Other		Total AllowanceTotal Allowance
Three Months Ended 2022
Beginning Balance$226.1 $191.3 $417.4 $144.6 $36.7 $181.3 $43.3 $53.7 $97.0 $24.3 
Uncollectible Expense— 17.1 17.1 — 3.8 3.8 — 4.7 4.7 2.5 
Uncollectible Costs Deferred (1)
0.9 14.8 15.7 (4.0)(2.1)(6.1)(3.3)5.4 2.1 1.0 
Write-Offs(2.3)(22.0)(24.3)(1.1)(0.5)(1.6)(0.3)(10.6)(10.9)(1.8)
Recoveries Collected0.8 5.5 6.3 0.6 2.5 3.1 — 1.9 1.9 0.2 
Ending Balance$225.5 $206.7 $432.2 $140.1 $40.4 $180.5 $39.7 $55.1 $94.8 $26.2 
Three Months Ended 2021
Beginning Balance$194.8 $164.1 $358.9 $129.1 $28.3 $157.4 $39.7 $51.9 $91.6 $17.2 
Uncollectible Expense— 16.3 16.3 — 3.8 3.8 — 3.9 3.9 1.2 
Uncollectible Costs Deferred (1)
5.4 27.1 32.5 11.9 7.5 19.4 (8.5)8.4 (0.1)1.2 
Write-Offs(3.3)(16.7)(20.0)(2.9)(4.0)(6.9)(0.1)(7.5)(7.6)(2.5)
Recoveries Collected0.4 3.6 4.0 0.3 1.1 1.4 — 1.5 1.5 0.2 
Ending Balance$197.3 $194.4 $391.7 $138.4 $36.7 $175.1 $31.1 $58.2 $89.3 $17.3 
(1) These expected credit losses are deferred as regulatory costs on the balance sheets, as these amounts are ultimately recovered in rates. Amounts include uncollectible costs for hardship accounts and other customer receivables, including uncollectible amounts related to uncollectible energy supply costs and COVID-19.
Components of Other Income, Net
The components of Other Income, Net on the statements of income were as follows:
 For the Three Months Ended
 March 31, 2022March 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR ElectricPSNHEversourceCL&PNSTAR ElectricPSNH
Pension, SERP and PBOP Non-Service
   Income Components		$54.3 $15.9 $21.0 $6.6 $20.1 $2.7 $10.1 $2.7 
AFUDC Equity9.9 2.8 4.9 0.4 9.2 1.7 6.2 0.6 
Equity in Earnings of Unconsolidated Affiliates0.4 — — — 3.7 — 0.1 — 
Investment (Loss)/Income(0.2)(0.4)(0.3)0.2 (0.6)0.4 0.2 0.1 
Interest Income6.7 1.3 3.5 0.3 1.5 0.1 0.1 0.7 
Other0.5 — 0.1 — 0.3 — 0.1 0.1 
Total Other Income, Net$71.6 $19.6 $29.2 $7.5 $34.2 $4.9 $16.8 $4.2 
Other Taxes These gross receipts taxes are recorded separately with collections in Operating Revenues and with payments in Taxes Other Than Income Taxes on the statements of income as follows:
 For the Three Months Ended
(Millions of Dollars)March 31, 2022March 31, 2021
Eversource$48.6 $48.6 
CL&P37.8 39.2 
Non-cash Investing Activities
Non-cash investing activities include plant additions included in Accounts Payable as follows:
(Millions of Dollars)As of March 31, 2022As of March 31, 2021
Eversource$385.6 $262.9 
CL&P102.1 70.9 
NSTAR Electric85.8 68.2 
PSNH49.5 23.5 
Reconciliation of Cash Balances to Cash and Restricted Cash The following table reconciles cash as reported on the balance sheets to the cash and restricted cash balance as reported on the statements of cash flows:
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR ElectricPSNHEversourceCL&PNSTAR ElectricPSNH
Cash as reported on the Balance Sheets$46.2 $21.6 $0.7 $3.8 $66.8 $55.8 $0.7 $— 
Restricted cash included in:
Special Deposits73.3 8.7 17.3 16.6 78.2 18.7 17.4 31.4 
Marketable Securities26.0 0.3 0.1 0.5 31.3 0.3 0.1 0.5 
Other Long-Term Assets19.1 — — 3.2 44.7 — — 3.2 
Cash and Restricted Cash as reported on the
    Statements of Cash Flows
$164.6 $30.6 $18.1 $24.1 $221.0 $74.8 $18.2 $35.1 
v3.22.1
REGULATORY ACCOUNTING (Tables)
 3 Months Ended
Mar. 31, 2022
Regulated Operations [Abstract]  
Components of Regulatory Assets The components of regulatory assets were as follows:
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
Benefit Costs$1,452.5 $268.0 $386.9 $116.5 $1,481.0 $272.4 $395.5 $118.9 
Storm Costs, Net1,249.3 735.7 449.4 64.2 1,102.7 695.6 341.3 65.8 
Regulatory Tracking Mechanisms937.7 295.2 375.0 97.0 1,050.5 333.6 376.6 85.4 
Income Taxes, Net791.2 471.8 112.8 14.5 790.7 470.5 112.6 17.5 
Securitized Stranded Costs468.1 — — 468.1 478.9 — — 478.9 
Goodwill-related293.6 — 252.1 — 297.8 — 255.7 — 
Derivative Liabilities229.4 229.4 — — 249.2 249.2 — — 
Asset Retirement Obligations117.5 34.2 61.9 4.2 115.0 33.6 59.8 4.1 
Other Regulatory Assets162.1 28.9 35.4 14.7 150.0 29.9 37.7 15.8 
Total Regulatory Assets5,701.4 2,063.2 1,673.5 779.2 5,715.8 2,084.8 1,579.2 786.4 
Less:  Current Portion1,128.1 382.1 433.7 124.7 1,129.1 371.6 444.0 107.2 
Total Long-Term Regulatory Assets$4,573.3 $1,681.1 $1,239.8 $654.5 $4,586.7 $1,713.2 $1,135.2 $679.2 
Components of Regulatory Liabilities The components of regulatory liabilities were as follows:
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
EDIT due to Tax Cuts and Jobs Act of 2017$2,665.7 $992.7 $973.3 $356.1 $2,685.2 $996.1 $984.5 $359.2 
Cost of Removal667.2 108.6 388.2 19.1 649.6 100.1 381.0 17.2 
Regulatory Tracking Mechanisms571.8 226.7 237.2 94.9 448.4 182.0 185.1 107.0 
Benefit Costs128.3 — 103.1 — 133.5 — 107.4 — 
AFUDC - Transmission85.1 44.0 41.1 — 81.0 43.2 37.8 — 
CL&P Settlement Agreement and Storm
  Performance Penalty		12.9 12.9 — — 81.3 81.3 — — 
Other Regulatory Liabilities416.2 75.0 107.4 25.1 389.7 57.1 91.5 18.2 
Total Regulatory Liabilities4,547.2 1,459.9 1,850.3 495.2 4,468.7 1,459.8 1,787.3 501.6 
Less:  Current Portion652.4 251.6 279.3 106.4 602.4 266.5 228.2 120.2 
Total Long-Term Regulatory Liabilities$3,894.8 $1,208.3 $1,571.0 $388.8 $3,866.3 $1,193.3 $1,559.1 $381.4 
v3.22.1
PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION (Tables)
 3 Months Ended
Mar. 31, 2022
Property, Plant and Equipment [Abstract]  
Summary of Property, Plant, and Equipment
The following tables summarize property, plant and equipment by asset category:
EversourceAs of March 31, 2022As of December 31, 2021
(Millions of Dollars)
Distribution - Electric$17,809.0 $17,679.1 
Distribution - Natural Gas6,713.7 6,694.8 
Transmission - Electric13,011.0 12,882.4 
Distribution - Water1,924.9 1,900.9 
Solar 200.9 200.9 
Utility39,659.5 39,358.1 
Other (1)
1,509.6 1,469.5 
Property, Plant and Equipment, Gross41,169.1 40,827.6 
Less:  Accumulated Depreciation  
Utility   (8,976.2)(8,885.2)
Other(609.8)(580.1)
Total Accumulated Depreciation(9,586.0)(9,465.3)
Property, Plant and Equipment, Net31,583.1 31,362.3 
Construction Work in Progress2,269.5 2,015.4 
Total Property, Plant and Equipment, Net$33,852.6 $33,377.7 
 As of March 31, 2022As of December 31, 2021
(Millions of Dollars)CL&PNSTAR
Electric		PSNHCL&PNSTAR
Electric		PSNH
Distribution - Electric$7,188.9 $8,151.1 $2,509.3 $7,117.6 $8,105.5 $2,496.2 
Transmission - Electric5,912.5 5,137.1 1,963.1 5,859.0 5,090.5 1,934.6 
Solar— 200.9 — — 200.9 — 
Property, Plant and Equipment, Gross
13,101.4 13,489.1 4,472.4 12,976.6 13,396.9 4,430.8 
Less:  Accumulated Depreciation
(2,592.6)(3,271.8)(912.8)(2,572.1)(3,227.3)(908.4)
Property, Plant and Equipment, Net
10,508.8 10,217.3 3,559.6 10,404.5 10,169.6 3,522.4 
Construction Work in Progress
432.2 791.6 163.0 399.0 707.0 134.1 
Total Property, Plant and Equipment, Net
$10,941.0 $11,008.9 $3,722.6 $10,803.5 $10,876.6 $3,656.5 

(1)    These assets are primarily comprised of computer software, hardware and equipment at Eversource Service and buildings at The Rocky River Realty Company.
v3.22.1
DERIVATIVE INSTRUMENTS (Tables)
 3 Months Ended
Mar. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Gross Fair Values and Net Amounts of Contracts The following table presents the gross fair values of contracts, categorized by risk type, and the net amounts recorded as current or long-term derivative assets or liabilities:
 As of March 31, 2022As of December 31, 2021
CL&P
(Millions of Dollars)
Fair Value HierarchyCommodity Supply and Price Risk
Management
Netting (1)
Net Amount
Recorded as a Derivative		Commodity Supply and Price Risk
Management
Netting (1)
Net Amount
Recorded as
a Derivative
Current Derivative AssetsLevel 3$14.8 $(0.4)$14.4 $14.7 $(1.0)$13.7 
Long-Term Derivative AssetsLevel 341.4 (1.3)40.1 46.9 (0.9)46.0 
Current Derivative LiabilitiesLevel 3(74.4)— (74.4)(73.5)— (73.5)
Long-Term Derivative LiabilitiesLevel 3(209.5)— (209.5)(235.4)— (235.4)
    (1)    Amounts represent derivative assets and liabilities that Eversource elected to record net on the balance sheets.  These amounts are subject to master netting agreements or similar agreements for which the right of offset exists.
Summary of Level 3 Derivative Contracts and Significant Unobservable Inputs Used
The following is a summary of the significant unobservable inputs utilized in the valuations of the derivative contracts classified as Level 3:
 As of March 31, 2022As of December 31, 2021
CL&PRangeAveragePeriod CoveredRangeAveragePeriod Covered
Forward Reserve Prices$0.50 —$1.15$0.82 per kW-Month2022 - 2024$0.50 —$1.15$0.82 per kW-Month2022 - 2024
Changes in the Level 3 Category of Derivative Assets Measured at Fair Value on a Recurring Basis
The following table presents changes in the Level 3 category of derivative assets and derivative liabilities measured at fair value on a recurring basis.  The derivative assets and liabilities are presented on a net basis.
CL&PFor the Three Months Ended March 31,
(Millions of Dollars)20222021
Derivatives, Net:
Fair Value as of Beginning of Period$(249.2)$(293.1)
Net Realized/Unrealized Gains/(Losses) Included in Regulatory Assets6.2 (12.5)
Settlements13.6 12.5 
Fair Value as of End of Period$(229.4)$(293.1)
v3.22.1
MARKETABLE SECURITIES (Tables)
 3 Months Ended
Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]  
Summary of Available-for-Sale Debt Securities The following is a summary of the available-for-sale debt securities:
As of March 31, 2022As of December 31, 2021
Eversource
(Millions of Dollars)
Amortized CostPre-Tax
Unrealized Gains		Pre-Tax
Unrealized
Losses		Fair ValueAmortized CostPre-Tax
Unrealized Gains		Pre-Tax
Unrealized
Losses		Fair Value
Debt Securities$211.4 $0.5 $(3.6)$208.3 $214.5 $5.1 $(0.2)$219.4 
Contractual Maturities of Available-for-Sale Debt Securities
As of March 31, 2022, the contractual maturities of available-for-sale debt securities were as follows:
 
Eversource
(Millions of Dollars)
Amortized CostFair Value
Less than one year (1)
$27.0 $27.0 
One to five years61.9 61.6 
Six to ten years36.3 35.5 
Greater than ten years86.2 84.2 
Total Debt Securities$211.4 $208.3 

(1)    Amounts in the Less than one year category include securities in the CYAPC and YAEC spent nuclear fuel trusts, which are restricted and are classified in long-term Marketable Securities on the balance sheets.
Marketable Securities Recorded at Fair Value on a Recurring Basis by Level The following table presents the marketable securities recorded at fair value on a recurring basis by the level in which they are classified within the fair value hierarchy:
Eversource
(Millions of Dollars)
As of March 31, 2022As of December 31, 2021
Level 1:    
Mutual Funds and Equities$227.0 $254.2 
Money Market Funds26.0 31.3 
Total Level 1$253.0 $285.5 
Level 2:  
U.S. Government Issued Debt Securities (Agency and Treasury)$80.0 $81.3 
Corporate Debt Securities62.5 65.3 
Asset-Backed Debt Securities11.6 12.6 
Municipal Bonds11.7 12.3 
Other Fixed Income Securities16.5 16.6 
Total Level 2$182.3 $188.1 
Total Marketable Securities$435.3 $473.6 
v3.22.1
SHORT-TERM AND LONG-TERM DEBT (Tables)
 3 Months Ended
Mar. 31, 2022
Debt Disclosure [Abstract]  
Borrowings Outstanding and Available under the Commercial Paper Programs
The amount of borrowings outstanding and available under the commercial paper programs were as follows:
Borrowings Outstanding as ofAvailable Borrowing Capacity as ofWeighted-Average Interest Rate as of
March 31, 2022December 31, 2021March 31, 2022December 31, 2021March 31, 2022December 31, 2021
(Millions of Dollars)
Eversource Parent Commercial Paper Program $1,393.8 $1,343.0 $606.2 $657.0 0.93 %0.31 %
NSTAR Electric Commercial Paper Program 275.0 162.5 375.0 487.5 0.43 %0.14 %
Summary of Long-Term Debt Issuance and Repayments The following table summarizes long-term debt issuances and repayments:
(Millions of Dollars)Issuance/(Repayment)Issue Date or Repayment DateMaturity DateUse of Proceeds for Issuance/
Repayment Information
Eversource Parent 2.90% Series V Senior Notes
$650.0 February 2022March 2027
Repaid Series K Senior Notes at maturity and short-term debt
Eversource Parent 3.38% Series W Senior Notes
650.0 February 2022March 2032
Repaid Series K Senior Notes at maturity and short-term debt
Eversource Parent 2.75% Series K Senior Notes
(750.0)March 2022March 2022Paid at maturity
Yankee Gas 8.48% Series B First Mortgage Bonds
(20.0)March 2022March 2022Paid at maturity
v3.22.1
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES (Tables)
 3 Months Ended
Mar. 31, 2022
Rate Reduction Bonds and Variable Interest Entity [Abstract]  
Summary of the Impact of Funding on the Balance Sheets and Income Statements
The following tables summarize the impact of PSNH Funding on PSNH's balance sheets and income statements:
(Millions of Dollars)
PSNH Balance Sheets:As of March 31, 2022As of December 31, 2021
Restricted Cash - Current Portion (included in Current Assets)$16.3 $31.1 
Restricted Cash - Long-Term Portion (included in Other Long-Term Assets)3.2 3.2 
Securitized Stranded Cost (included in Regulatory Assets)468.1 478.9 
Other Regulatory Liabilities (included in Regulatory Liabilities)6.0 5.4 
Accrued Interest (included in Other Current Liabilities)2.9 7.5 
Rate Reduction Bonds - Current Portion43.2 43.2 
Rate Reduction Bonds - Long-Term Portion432.1 453.7 

(Millions of Dollars)
PSNH Income Statements:
For the Three Months Ended
March 31, 2022March 31, 2021
Amortization of RRB Principal (included in Amortization of Regulatory Assets, Net)$10.8 $10.8 
Interest Expense on RRB Principal (included in Interest Expense)4.4 4.7 
v3.22.1
PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION (Tables)
 3 Months Ended
Mar. 31, 2022
Postemployment Benefits [Abstract]  
Components of Net Periodic Benefit Expense/(Income)
The components of net periodic benefit plan expense/(income) for the Pension, SERP and PBOP Plans, prior to amounts capitalized as Property, Plant and Equipment or deferred as regulatory assets/(liabilities) for future recovery or refund, are shown below.  The service cost component of net periodic benefit plan expense/(income), less the capitalized portion, is included in Operations and Maintenance expense on the statements of income. The remaining components of net periodic benefit plan expense/(income), less the deferred portion, are included in Other Income, Net on the statements of income. Pension, SERP and PBOP expense/(income) reflected in the statements of cash flows for CL&P, NSTAR Electric and PSNH does not include intercompany allocations of net periodic benefit plan expense/(income), as these amounts are cash settled on a short-term basis.

Pension and SERPPBOP
For the Three Months Ended March 31, 2022For the Three Months Ended March 31, 2022
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
Service Cost$17.7 $4.5 $3.6 $1.8 $2.8 $0.5 $0.5 $0.2 
Interest Cost38.6 7.8 8.1 4.2 5.0 0.9 1.3 0.5 
Expected Return on Plan Assets(131.7)(26.6)(32.0)(14.1)(22.4)(2.8)(10.6)(1.6)
Actuarial Losses, net30.7 4.2 8.5 2.2 — — — — 
Prior Service Cost/(Credit)0.4 — 0.1 — (5.4)0.2 (4.3)0.1 
Total Net Periodic Benefit Plan Income$(44.3)$(10.1)$(11.7)$(5.9)$(20.0)$(1.2)$(13.1)$(0.8)
Intercompany Income AllocationsN/A$(3.8)$(2.9)$(0.8)N/A$(0.9)$(0.9)$(0.3)
Pension and SERPPBOP
For the Three Months Ended March 31, 2021For the Three Months Ended March 31, 2021
(Millions of Dollars)EversourceCL&PNSTAR
Electric		PSNHEversourceCL&PNSTAR
Electric		PSNH
Service Cost$21.3 $6.3 $4.0 $2.2 $3.5 $0.6 $0.6 $0.3 
Interest Cost32.6 7.3 6.7 3.6 4.4 0.8 1.1 0.5 
Expected Return on Plan Assets(108.9)(21.6)(26.9)(11.9)(19.7)(2.6)(9.3)(1.5)
Actuarial Loss61.6 13.0 15.5 4.9 2.6 0.4 0.6 0.3 
Prior Service Cost/(Credit)0.3 — 0.1 — (5.3)0.2 (4.2)0.1 
Total Net Periodic Benefit Plan Expense/(Income)$6.9 $5.0 $(0.6)$(1.2)$(14.5)$(0.6)$(11.2)$(0.3)
Intercompany Expense/(Income) AllocationsN/A$1.3 $1.5 $0.5 N/A$(0.3)$(0.4)$(0.1)
v3.22.1
COMMITMENTS AND CONTINGENCIES (Tables)
 3 Months Ended
Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]  
Environmental Sites and Related Reserves
The number of environmental sites and related reserves for which remediation or long-term monitoring, preliminary site work or site assessment is being performed are as follows:
 As of March 31, 2022As of December 31, 2021
Number of SitesReserve
(in millions)		Number of SitesReserve
(in millions)
Eversource61 $117.8 61 $115.4 
CL&P14 14.3 14 13.9 
NSTAR Electric11 3.2 11 3.3 
PSNH9 6.4 9 6.3 
Non-Cancelable Commitments under Purchase Commitment Contracts Renewable energy contracts include non-cancelable commitments under contracts of NSTAR Electric for the purchase of energy and RECs from renewable energy facilities.
NSTAR Electric      
(Millions of Dollars)20222023202420252026ThereafterTotal
Renewable Energy$75.6 $78.3 $269.4 $315.8 $322.1 $5,812.2 $6,873.4 
Summary of Exposure to Guarantees and Indemnifications
The following table summarizes Eversource parent's exposure to guarantees and indemnifications of its subsidiaries and affiliates to external parties:  
As of March 31, 2022
Company (Obligor)DescriptionMaximum Exposure
(in millions)		Expiration Dates
North East Offshore LLC
Construction-related purchase agreements with third-party contractors (1)
$936.3 
 (1)
Sunrise Wind LLC
Construction-related purchase agreements with third-party contractors (2)
330.6 
2026
Revolution Wind, LLC
Construction-related purchase agreements with third-party contractors (3)
254.7 2024 - 2027
South Fork Wind, LLC
Construction-related purchase agreements with third-party contractors (4)
165.3 2023 - 2026
Eversource Investment LLC
Funding and indemnification obligations of North East Offshore LLC (5)
107.8 
 (5)
South Fork Wind, LLC
Power Purchase Agreement Security (6)
7.1 
 (6)
Sunrise Wind LLC
OREC capacity production (7)
2.2 
 (7)
Bay State Wind LLCReal estate purchase2.5 2022
South Fork Wind, LLC
Transmission interconnection
1.2 —
Eversource Investment LLC
Letters of Credit (8)
4.3 —
Various
Surety bonds (9)
35.0 2022 - 2023
Eversource ServiceLease payments for real estate0.7 2024

(1)    Eversource parent issued guarantees on behalf of its 50 percent-owned affiliate, North East Offshore LLC (NEO), under which Eversource parent agreed to guarantee 50 percent of NEO’s performance of obligations under certain purchase agreements with third-party contactors, in an aggregate amount not to exceed $1.3 billion with an expiration date in 2025. Eversource parent also issued a separate guarantee to Ørsted on behalf of NEO, under which Eversource parent agreed to guarantee 50 percent of NEO’s payment obligations under certain offshore wind project construction-related agreements with Ørsted in an aggregate amount not to exceed $62.5 million and expiring upon full performance of the guaranteed obligation. Any amounts paid under this guarantee to Ørsted will count toward, but not increase, the maximum amount of the Funding Guarantee described in Note 5, below. The guarantee expires upon the full performance of the guaranteed obligations.

(2)     Eversource parent issued a guaranty on behalf of its 50 percent-owned affiliate, Sunrise Wind LLC, whereby Eversource parent will guarantee Sunrise Wind LLC's performance of certain obligations, in an aggregate amount not to exceed $420.6 million, in connection with a construction-related purchase agreement. Eversource parent’s obligations under the guarantee expire upon the earlier of (i) April 2026 and (ii) full performance of the guaranteed obligations.     

(3)    Eversource parent issued guarantees on behalf of its 50 percent-owned affiliate, Revolution Wind, LLC, whereby Eversource parent will guarantee Revolution Wind, LLC's performance of certain obligations, in an aggregate amount not to exceed $268.5 million, in connection with construction-related purchase agreements. Eversource parent’s obligations under the guarantees expire upon the earlier of (i) dates ranging from November 2024 and November 2027 and (ii) full performance of the guaranteed obligations.

(4)    Eversource parent issued guarantees on behalf of its 50 percent-owned affiliate, South Fork Wind, LLC, whereby Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations in connection with construction-related purchase agreements. Under these guarantees, Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations, in a total aggregate amount not to exceed $184.0 million. Eversource parent’s obligations under these guarantees expire upon the earlier of (i) dates ranging from June 2023 and August 2026 and (ii) full performance of the guaranteed obligations.

(5)    Eversource parent issued a guarantee (Funding Guarantee) on behalf of Eversource Investment LLC (EI), its wholly-owned subsidiary that holds a 50 percent ownership interest in NEO, under which Eversource parent agreed to guarantee certain funding obligations and certain indemnification payments of EI under the operating agreement of NEO, in an amount not to exceed $910 million. The guaranteed obligations include payment of EI's funding obligations during the construction phase of NEO’s underlying offshore wind projects and indemnification obligations associated with third party credit support for its investment in NEO. Eversource parent’s obligations under the Funding Guarantee expire upon the full performance of the guaranteed obligations.
(6)    Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, South Fork Wind, LLC, whereby Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations, in an amount not to exceed $7.1 million, under a Power Purchase Agreement between the Long Island Power Authority and South Fork Wind, LLC (the Agreement). The guarantee expires upon the later of (i) the end of the Agreement term and (ii) full performance of the guarantee obligations.

(7)    Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, Sunrise Wind LLC, whereby Eversource parent will guarantee Sunrise Wind LLC's performance of certain obligations, in an amount not to exceed $15.4 million, under the Offshore Wind Renewable Energy Certificate Purchase and Sale Agreement (the Agreement). The Agreement was executed by and between the New York State Energy Research and Development Authority (NYSERDA) and Sunrise Wind LLC. The guarantee expires upon the full performance of the guaranteed obligations.    

(8)    On September 16, 2020, Eversource parent entered into a guarantee on behalf of EI, which holds Eversource's investments in offshore wind-related equity method investments, under which Eversource parent would guarantee EI's obligations under a letter of credit facility with a financial institution that EI may request in an aggregate amount of up to approximately $25 million. In January 2022, Eversource parent issued two letters of credit on behalf of South Fork Wind, LLC related to future decommissioning obligations of certain onshore transmission assets totaling $4.3 million.

(9)    Surety bond expiration dates reflect termination dates, the majority of which will be renewed or extended.  Certain surety bonds contain credit ratings triggers that would require Eversource parent to post collateral in the event that the unsecured debt credit ratings of Eversource parent are downgraded.
v3.22.1
FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)
 3 Months Ended
Mar. 31, 2022
Fair Value Disclosures [Abstract]  
Carrying Amounts and Estimated Fair Values of Financial Instruments Carrying amounts and estimated fair values are as follows:
 EversourceCL&PNSTAR ElectricPSNH
(Millions of Dollars)Carrying
Amount		Fair
Value		Carrying
Amount		Fair
Value		Carrying
Amount		Fair
Value		Carrying
Amount		Fair
Value
As of March 31, 2022:        
Preferred Stock Not Subject to Mandatory Redemption
$155.6 $158.3 $116.2 $115.5 $43.0 $42.8 $— $— 
Long-Term Debt18,729.6 18,562.3 4,215.7 4,392.2 3,986.3 4,094.1 1,164.0 1,086.3 
Rate Reduction Bonds475.3 492.8 — — — — 475.3 492.8 
As of December 31, 2021:        
Preferred Stock Not Subject to Mandatory Redemption
$155.6 $166.3 $116.2 $122.3 $43.0 $44.0 $— $— 
Long-Term Debt18,216.7 19,636.3 4,215.4 4,848.9 3,985.4 4,453.5 1,163.8 1,220.6 
Rate Reduction Bonds496.9 543.3 — — — — 496.9 543.3 
v3.22.1
ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Tables)
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
Changes in Accumulated Other Comprehensive Income/(Loss) by Component, Net of Tax
The changes in accumulated other comprehensive income/(loss) by component, net of tax, are as follows:
For the Three Months Ended March 31, 2022For the Three Months Ended March 31, 2021
Eversource
(Millions of Dollars)
Qualified
Cash Flow
Hedging
Instruments		Unrealized
Gains/(Losses) on Marketable
Securities		Defined
Benefit Plans		TotalQualified
Cash Flow
Hedging
Instruments		Unrealized
Gains/(Losses) on Marketable
Securities		Defined
Benefit Plans		Total
Balance as of Beginning of Period$(0.4)$0.4 $(42.3)$(42.3)$(1.4)$1.1 $(76.1)$(76.4)
OCI Before Reclassifications
— (0.8)— (0.8)— (0.7)— (0.7)
Amounts Reclassified from AOCI
— — 1.5 1.5 0.4 — 1.5 1.9 
Net OCI— (0.8)1.5 0.7 0.4 (0.7)1.5 1.2 
Balance as of End of Period$(0.4)$(0.4)$(40.8)$(41.6)$(1.0)$0.4 $(74.6)$(75.2)
v3.22.1
COMMON SHARES (Tables)
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
Common Shares Authorized and Issued
The following table sets forth the Eversource parent common shares and the shares of common stock of CL&P, NSTAR Electric and PSNH that were authorized and issued, as well as the respective per share par values:  
 Shares
 Authorized as of March 31, 2022 and December 31, 2021Issued as of
 Par ValueMarch 31, 2022December 31, 2021
Eversource$5 380,000,000 357,818,402 357,818,402 
CL&P$10 24,500,000 6,035,205 6,035,205 
NSTAR Electric$1 100,000,000 200 200 
PSNH$1 100,000,000 301 301 
v3.22.1
EARNINGS PER SHARE (Tables)
 3 Months Ended
Mar. 31, 2022
Earnings Per Share [Abstract]  
Components of Basic and Diluted EPS
The following table sets forth the components of basic and diluted EPS:
Eversource
(Millions of Dollars, except share information)
For the Three Months Ended
March 31, 2022March 31, 2021
Net Income Attributable to Common Shareholders$443.4 $366.1 
Weighted Average Common Shares Outstanding:  
Basic345,156,346 343,678,243 
Dilutive Effect504,787 656,446 
Diluted345,661,133 344,334,689 
Basic EPS$1.28 $1.07 
Diluted EPS$1.28 $1.06 
v3.22.1
REVENUES (Tables)
 3 Months Ended
Mar. 31, 2022
Revenue from Contract with Customer [Abstract]  
Operating Revenues Disaggregated by Revenue Source
The following tables present operating revenues disaggregated by revenue source:
For the Three Months Ended March 31, 2022
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
Revenues from Contracts with Customers
Retail Tariff Sales
Residential $1,186.2 $556.8 $— $28.2 $— $— $1,771.2 
Commercial 661.3 257.6 — 14.6 — (1.1)932.4 
Industrial89.6 68.1 — 1.1 — (4.5)154.3 
Total Retail Tariff Sales Revenues1,937.1 882.5 — 43.9 — (5.6)2,857.9 
Wholesale Transmission Revenues— — 446.2 — 24.4 (364.7)105.9 
Wholesale Market Sales Revenues365.5 33.5 — 0.8 — — 399.8 
Other Revenues from Contracts with Customers17.7 1.0 3.8 1.9 359.1 (353.1)30.4 
Amortization of/(Reserve for)
    Revenues Subject to Refund (1)
58.4 — — (0.4)— — 58.0 
Total Revenues from Contracts with Customers2,378.7 917.0 450.0 46.2 383.5 (723.4)3,452.0 
Alternative Revenue Programs4.8 10.2 (15.0)2.2 — 13.6 15.8 
Other Revenues (2)
2.8 0.4 0.2 0.1 — — 3.5 
Total Operating Revenues$2,386.3 $927.6 $435.2 $48.5 $383.5 $(709.8)$3,471.3 
For the Three Months Ended March 31, 2021
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
Revenues from Contracts with Customers
Retail Tariff Sales
Residential $1,066.0 $466.3 $— $27.7 $— $— $1,560.0 
Commercial 559.9 207.6 — 13.8 — (1.4)779.9 
Industrial83.0 55.9 — 1.0 — (3.5)136.4 
Total Retail Tariff Sales Revenues1,708.9 729.8 — 42.5 — (4.9)2,476.3 
Wholesale Transmission Revenues— — 394.3 — 19.2 (321.0)92.5 
Wholesale Market Sales Revenues149.1 26.4 — 0.8 — — 176.3 
Other Revenues from Contracts with Customers18.2 1.3 3.4 1.2 323.8 (321.3)26.6 
Total Revenues from Contracts with Customers1,876.2 757.5 397.7 44.5 343.0 (647.2)2,771.7 
Alternative Revenue Programs23.0 22.8 2.7 1.8 — 2.2 52.5 
Other Revenues (2)
1.1 0.2 0.2 0.1 — — 1.6 
Total Operating Revenues$1,900.3 $780.5 $400.6 $46.4 $343.0 $(645.0)$2,825.8 
For the Three Months Ended March 31, 2022For the Three Months Ended March 31, 2021
(Millions of Dollars)CL&PNSTAR ElectricPSNHCL&PNSTAR ElectricPSNH
Revenues from Contracts with Customers
Retail Tariff Sales
Residential $599.1 $404.6 $182.5 $545.8 $362.4 $157.8 
Commercial 242.2 331.3 88.4 214.2 268.3 77.8 
Industrial33.5 34.1 22.0 36.7 24.6 21.7 
Total Retail Tariff Sales Revenues874.8 770.0 292.9 796.7 655.3 257.3 
Wholesale Transmission Revenues209.1 165.2 71.9 189.0 147.1 58.2 
Wholesale Market Sales Revenues279.9 57.9 27.7 109.7 24.4 15.0 
Other Revenues from Contracts with Customers7.9 11.6 2.6 7.3 11.7 3.2 
Amortization of Revenues Subject to Refund (1)
58.4 — — — — — 
Total Revenues from Contracts with Customers1,430.1 1,004.7 395.1 1,102.7 838.5 333.7 
Alternative Revenue Programs1.3 (8.2)(3.3)8.9 13.8 3.0 
Other Revenues (2)
0.1 2.0 0.9 0.2 1.1 — 
Eliminations(145.7)(135.3)(53.3)(124.5)(116.4)(43.3)
Total Operating Revenues$1,285.8 $863.2 $339.4 $987.3 $737.0 $293.4 
(1)    Amortization of Revenues Subject to Refund within the Electric Distribution segment in the first quarter of 2022 represents customer credits being distributed to CL&P’s customers on retail electric bills as a result of the October 2021 CL&P settlement agreement and the 2021 civil penalty for non-compliance with storm performance standards. Total customer credits as a result of the 2021 settlement and civil penalty were $93.4 million. The settlement amount of $65 million was refunded over a two-month billing period from December 1, 2021 to January 31, 2022 and the civil penalty of $28.4 million is being refunded over a one year billing period, which began September 1, 2021. (2)    Other Revenues include certain fees charged to customers that are not considered revenue from contracts with customers. Other Revenues also include lease revenues under lessor accounting guidance of $1.0 million (including $0.2 million at CL&P and $0.6 million at NSTAR Electric) and $1.6 million (including $0.2 million at CL&P and $1.1 million at NSTAR Electric) for the three months ended March 31, 2022 and 2021, respectively.
v3.22.1
SEGMENT INFORMATION (Tables)
 3 Months Ended
Mar. 31, 2022
Segment Reporting [Abstract]  
Summary of Segment Information and Segmented Total Assets
Eversource's segment information is as follows:
For the Three Months Ended March 31, 2022
Eversource
(Millions of Dollars)
Electric DistributionNatural Gas DistributionElectric TransmissionWater DistributionOtherEliminationsTotal
Operating Revenues$2,386.3 $927.6 $435.2 $48.5 $383.5 $(709.8)$3,471.3 
Depreciation and Amortization(351.6)(51.9)(81.9)(12.3)(30.2)1.6 (526.3)
Other Operating Expenses(1,845.6)(657.3)(129.3)(27.1)(331.4)708.8 (2,281.9)
Operating Income$189.1 $218.4 $224.0 $9.1 $21.9 $0.6 $663.1 
Interest Expense$(59.4)$(15.8)$(33.2)$(8.2)$(46.8)$10.1 $(153.3)
Other Income, Net47.6 10.1 8.9 2.2 495.9 (493.1)71.6 
Net Income Attributable to Common Shareholders140.9 164.0 148.5 3.7 468.7 (482.4)443.4 
Cash Flows Used for Investments in Plant280.5 127.3 266.9 27.8 62.1 — 764.6 
For the Three Months Ended March 31, 2021
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
Operating Revenues$1,900.3 $780.5 $400.6 $46.4 $343.0 $(645.0)$2,825.8 
Depreciation and Amortization(221.9)(45.7)(73.5)(11.3)(27.3)1.0 (378.7)
Other Operating Expenses(1,530.5)(535.8)(115.4)(25.1)(299.5)644.8 (1,861.5)
Operating Income$147.9 $199.0 $211.7 $10.0 $16.2 $0.8 $585.6 
Interest Expense$(53.3)$(13.9)$(32.7)$(7.9)$(41.6)$11.6 $(137.8)
Other Income, Net20.7 3.9 5.5 1.0 424.1 (421.0)34.2 
Net Income Attributable to Common Shareholders93.2 147.6 135.4 3.6 394.9 (408.6)366.1 
Cash Flows Used for Investments in Plant256.6 131.8 225.2 27.6 47.8 — 689.0 
The following table summarizes Eversource's segmented total assets:
Eversource
(Millions of Dollars)
Electric
Distribution		Natural Gas
Distribution		Electric
Transmission		Water DistributionOtherEliminationsTotal
As of March 31, 2022$25,883.2 $7,329.7 $12,757.8 $2,572.1 $23,394.3 $(22,647.9)$49,289.2 
As of December 31, 202125,411.2 7,215.9 12,377.8 2,551.1 22,674.7 (21,738.6)48,492.1 
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)
$ in Thousands, customer in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
customer
utility
May 04, 2022
Dec. 31, 2021
USD ($)
Mar. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Summary of Accounting Policies [Line Items]          
Investments in unconsolidated affiliates $ 1,545,433   $ 1,436,293    
Number of electric, natural gas and water customers | customer 4.4        
Allowance for uncollectible accounts for late fees and other receivable amounts $ 432,200   417,400 $ 391,700 $ 358,900
Cash, cash equivalents, restricted cash and restricted cash equivalents 164,589   221,008 175,604 264,950
Energy Relief Fund - Merrimack Valley Programs          
Summary of Accounting Policies [Line Items]          
Restricted cash, current 20,000        
Energy Relief Fund - Merrimack Valley Programs | Other Long-Term Assets          
Summary of Accounting Policies [Line Items]          
Restricted cash, noncurrent 15,900        
Restricted cash     41,500    
COVID-19          
Summary of Accounting Policies [Line Items]          
Allowance for uncollectible accounts for late fees and other receivable amounts 58,500   55,300    
CL&P          
Summary of Accounting Policies [Line Items]          
Allowance for uncollectible accounts for late fees and other receivable amounts $ 180,500   181,300 175,100 157,400
Period of accounts receivable recoverable under financial or medical duress 180 days        
Cash, cash equivalents, restricted cash and restricted cash equivalents $ 30,584   74,788 18,288 99,809
CL&P | Customer Assistance Fund          
Summary of Accounting Policies [Line Items]          
Cash, cash equivalents, restricted cash and restricted cash equivalents 10,000   10,000    
CL&P | COVID-19          
Summary of Accounting Policies [Line Items]          
Allowance for uncollectible accounts for late fees and other receivable amounts 20,400   23,900    
NSTAR Electric          
Summary of Accounting Policies [Line Items]          
Allowance for uncollectible accounts for late fees and other receivable amounts 94,800   97,000 89,300 91,600
Cash, cash equivalents, restricted cash and restricted cash equivalents 18,144   18,179 17,373 17,410
NSTAR Electric | COVID-19          
Summary of Accounting Policies [Line Items]          
Allowance for uncollectible accounts for late fees and other receivable amounts 9,000   9,000    
PSNH          
Summary of Accounting Policies [Line Items]          
Allowance for uncollectible accounts for late fees and other receivable amounts 26,200   24,300 17,300 17,200
Cash, cash equivalents, restricted cash and restricted cash equivalents 24,058   35,126 $ 27,988 $ 39,555
PSNH | COVID-19          
Summary of Accounting Policies [Line Items]          
Allowance for uncollectible accounts for late fees and other receivable amounts $ 0   0    
Yankee Gas          
Summary of Accounting Policies [Line Items]          
Period of accounts receivable recoverable under financial or medical duress 90 days        
Connecticut, Massachusetts and New Hampshire          
Summary of Accounting Policies [Line Items]          
Number of regulated utilities | utility 10        
Offshore Wind Business          
Summary of Accounting Policies [Line Items]          
Investments in unconsolidated affiliates $ 1,330,000   $ 1,210,000    
Offshore Wind Business | Subsequent Event          
Summary of Accounting Policies [Line Items]          
Ownership interest   50.00%      
North East Offshore LLC          
Summary of Accounting Policies [Line Items]          
Ownership interest 50.00%        
North East Offshore LLC | Subsequent Event          
Summary of Accounting Policies [Line Items]          
Ownership interest   50.00%      
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Provision for Uncollectible Accounts (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance $ 417,400 $ 358,900
Uncollectible Expense 17,135 16,295
Uncollectible Costs Deferred 15,700 32,500
Write-Offs (24,300) (20,000)
Recoveries Collected 6,300 4,000
Ending Balance 432,200 391,700
CL&P    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 181,300 157,400
Uncollectible Expense 3,776 3,797
Uncollectible Costs Deferred (6,100) 19,400
Write-Offs (1,600) (6,900)
Recoveries Collected 3,100 1,400
Ending Balance 180,500 175,100
NSTAR Electric    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 97,000 91,600
Uncollectible Expense 4,662 3,868
Uncollectible Costs Deferred 2,100 (100)
Write-Offs (10,900) (7,600)
Recoveries Collected 1,900 1,500
Ending Balance 94,800 89,300
PSNH    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 24,300 17,200
Uncollectible Expense 2,496 1,221
Uncollectible Costs Deferred 1,000 1,200
Write-Offs (1,800) (2,500)
Recoveries Collected 200 200
Ending Balance 26,200 17,300
Hardship Accounts    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 226,100 194,800
Uncollectible Expense 0 0
Uncollectible Costs Deferred 900 5,400
Write-Offs (2,300) (3,300)
Recoveries Collected 800 400
Ending Balance 225,500 197,300
Hardship Accounts | CL&P    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 144,600 129,100
Uncollectible Expense 0 0
Uncollectible Costs Deferred (4,000) 11,900
Write-Offs (1,100) (2,900)
Recoveries Collected 600 300
Ending Balance 140,100 138,400
Hardship Accounts | NSTAR Electric    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 43,300 39,700
Uncollectible Expense 0 0
Uncollectible Costs Deferred (3,300) (8,500)
Write-Offs (300) (100)
Recoveries Collected 0 0
Ending Balance 39,700 31,100
Retail (Non-Hardship), Wholesale, and Other    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 191,300 164,100
Uncollectible Expense 17,100 16,300
Uncollectible Costs Deferred 14,800 27,100
Write-Offs (22,000) (16,700)
Recoveries Collected 5,500 3,600
Ending Balance 206,700 194,400
Retail (Non-Hardship), Wholesale, and Other | CL&P    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 36,700 28,300
Uncollectible Expense 3,800 3,800
Uncollectible Costs Deferred (2,100) 7,500
Write-Offs (500) (4,000)
Recoveries Collected 2,500 1,100
Ending Balance 40,400 36,700
Retail (Non-Hardship), Wholesale, and Other | NSTAR Electric    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance 53,700 51,900
Uncollectible Expense 4,700 3,900
Uncollectible Costs Deferred 5,400 8,400
Write-Offs (10,600) (7,500)
Recoveries Collected 1,900 1,500
Ending Balance $ 55,100 $ 58,200
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Components of Other Income, Net (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Summary of Accounting Policies [Line Items]    
Other income, net $ 71,561 $ 34,201
Pension, SERP and PBOP Non-Service   Income Components    
Summary of Accounting Policies [Line Items]    
Other income, net 54,300 20,100
AFUDC Equity    
Summary of Accounting Policies [Line Items]    
Other income, net 9,900 9,200
Equity in Earnings of Unconsolidated Affiliates    
Summary of Accounting Policies [Line Items]    
Other income, net 400 3,700
Investment (Loss)/Income    
Summary of Accounting Policies [Line Items]    
Other income, net (200) (600)
Interest Income    
Summary of Accounting Policies [Line Items]    
Other income, net 6,700 1,500
Other    
Summary of Accounting Policies [Line Items]    
Other income, net 500 300
CL&P    
Summary of Accounting Policies [Line Items]    
Other income, net 19,564 4,908
CL&P | Pension, SERP and PBOP Non-Service   Income Components    
Summary of Accounting Policies [Line Items]    
Other income, net 15,900 2,700
CL&P | AFUDC Equity    
Summary of Accounting Policies [Line Items]    
Other income, net 2,800 1,700
CL&P | Equity in Earnings of Unconsolidated Affiliates    
Summary of Accounting Policies [Line Items]    
Other income, net 0 0
CL&P | Investment (Loss)/Income    
Summary of Accounting Policies [Line Items]    
Other income, net (400) 400
CL&P | Interest Income    
Summary of Accounting Policies [Line Items]    
Other income, net 1,300 100
CL&P | Other    
Summary of Accounting Policies [Line Items]    
Other income, net 0 0
NSTAR Electric    
Summary of Accounting Policies [Line Items]    
Other income, net 29,231 16,812
NSTAR Electric | Pension, SERP and PBOP Non-Service   Income Components    
Summary of Accounting Policies [Line Items]    
Other income, net 21,000 10,100
NSTAR Electric | AFUDC Equity    
Summary of Accounting Policies [Line Items]    
Other income, net 4,900 6,200
NSTAR Electric | Equity in Earnings of Unconsolidated Affiliates    
Summary of Accounting Policies [Line Items]    
Other income, net 0 100
NSTAR Electric | Investment (Loss)/Income    
Summary of Accounting Policies [Line Items]    
Other income, net (300) 200
NSTAR Electric | Interest Income    
Summary of Accounting Policies [Line Items]    
Other income, net 3,500 100
NSTAR Electric | Other    
Summary of Accounting Policies [Line Items]    
Other income, net 100 100
PSNH    
Summary of Accounting Policies [Line Items]    
Other income, net 7,509 4,166
PSNH | Pension, SERP and PBOP Non-Service   Income Components    
Summary of Accounting Policies [Line Items]    
Other income, net 6,600 2,700
PSNH | AFUDC Equity    
Summary of Accounting Policies [Line Items]    
Other income, net 400 600
PSNH | Equity in Earnings of Unconsolidated Affiliates    
Summary of Accounting Policies [Line Items]    
Other income, net 0 0
PSNH | Investment (Loss)/Income    
Summary of Accounting Policies [Line Items]    
Other income, net 200 100
PSNH | Interest Income    
Summary of Accounting Policies [Line Items]    
Other income, net 300 700
PSNH | Other    
Summary of Accounting Policies [Line Items]    
Other income, net $ 0 $ 100
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Other Taxes (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Schedule of Gross Tax Receipts [Line Items]    
Gross receipts taxes $ 48.6 $ 48.6
CL&P    
Schedule of Gross Tax Receipts [Line Items]    
Gross receipts taxes $ 37.8 $ 39.2
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Non-cash Investing Activities (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Schedule of Supplemental Cash Flow [Line Items]    
Plant additions included in accounts payable $ 385.6 $ 262.9
CL&P    
Schedule of Supplemental Cash Flow [Line Items]    
Plant additions included in accounts payable 102.1 70.9
NSTAR Electric    
Schedule of Supplemental Cash Flow [Line Items]    
Plant additions included in accounts payable 85.8 68.2
PSNH    
Schedule of Supplemental Cash Flow [Line Items]    
Plant additions included in accounts payable $ 49.5 $ 23.5
v3.22.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Reconciliation of Cash Balances to Cash and Restricted Cash (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Mar. 31, 2021
Dec. 31, 2020
Restricted Cash and Cash Equivalents Items [Line Items]        
Cash as reported on the Balance Sheets $ 46,175 $ 66,773    
Cash and Restricted Cash as reported on the Statements of Cash Flows 164,589 221,008 $ 175,604 $ 264,950
Special Deposits        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 73,300 78,200    
Marketable Securities        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 26,000 31,300    
Other Long-Term Assets        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 19,100 44,700    
CL&P        
Restricted Cash and Cash Equivalents Items [Line Items]        
Cash as reported on the Balance Sheets 21,628 55,804    
Cash and Restricted Cash as reported on the Statements of Cash Flows 30,584 74,788 18,288 99,809
CL&P | Special Deposits        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 8,700 18,700    
CL&P | Marketable Securities        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 300 300    
CL&P | Other Long-Term Assets        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 0 0    
NSTAR Electric        
Restricted Cash and Cash Equivalents Items [Line Items]        
Cash as reported on the Balance Sheets 721 745    
Cash and Restricted Cash as reported on the Statements of Cash Flows 18,144 18,179 17,373 17,410
NSTAR Electric | Special Deposits        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 17,300 17,400    
NSTAR Electric | Marketable Securities        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 100 100    
NSTAR Electric | Other Long-Term Assets        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 0 0    
PSNH        
Restricted Cash and Cash Equivalents Items [Line Items]        
Cash as reported on the Balance Sheets 3,827 15    
Cash and Restricted Cash as reported on the Statements of Cash Flows 24,058 35,126 $ 27,988 $ 39,555
PSNH | Special Deposits        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 16,600 31,400    
PSNH | Marketable Securities        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash 500 500    
PSNH | Other Long-Term Assets        
Restricted Cash and Cash Equivalents Items [Line Items]        
Restricted cash $ 3,200 $ 3,200    
v3.22.1
REGULATORY ACCOUNTING - Components of Regulatory Assets (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Regulatory Assets [Line Items]    
Total Regulatory Assets $ 5,701,400 $ 5,715,800
Less:  Current Portion 1,128,088 1,129,093
Total Long-Term Regulatory Assets 4,573,309 4,586,709
Benefit Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 1,452,500 1,481,000
Storm Costs, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 1,249,300 1,102,700
Regulatory Tracking Mechanisms    
Regulatory Assets [Line Items]    
Total Regulatory Assets 937,700 1,050,500
Income Taxes, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 791,200 790,700
Securitized Stranded Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 468,100 478,900
Goodwill-related    
Regulatory Assets [Line Items]    
Total Regulatory Assets 293,600 297,800
Derivative Liabilities    
Regulatory Assets [Line Items]    
Total Regulatory Assets 229,400 249,200
Asset Retirement Obligations    
Regulatory Assets [Line Items]    
Total Regulatory Assets 117,500 115,000
Other Regulatory Assets    
Regulatory Assets [Line Items]    
Total Regulatory Assets 162,100 150,000
CL&P    
Regulatory Assets [Line Items]    
Total Regulatory Assets 2,063,200 2,084,800
Less:  Current Portion 382,112 371,609
Total Long-Term Regulatory Assets 1,681,057 1,713,161
CL&P | Benefit Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 268,000 272,400
CL&P | Storm Costs, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 735,700 695,600
CL&P | Regulatory Tracking Mechanisms    
Regulatory Assets [Line Items]    
Total Regulatory Assets 295,200 333,600
CL&P | Income Taxes, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 471,800 470,500
CL&P | Securitized Stranded Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 0 0
CL&P | Goodwill-related    
Regulatory Assets [Line Items]    
Total Regulatory Assets 0 0
CL&P | Derivative Liabilities    
Regulatory Assets [Line Items]    
Total Regulatory Assets 229,400 249,200
CL&P | Asset Retirement Obligations    
Regulatory Assets [Line Items]    
Total Regulatory Assets 34,200 33,600
CL&P | Other Regulatory Assets    
Regulatory Assets [Line Items]    
Total Regulatory Assets 28,900 29,900
NSTAR Electric    
Regulatory Assets [Line Items]    
Total Regulatory Assets 1,673,500 1,579,200
Less:  Current Portion 433,653 443,956
Total Long-Term Regulatory Assets 1,239,773 1,135,231
NSTAR Electric | Benefit Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 386,900 395,500
NSTAR Electric | Storm Costs, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 449,400 341,300
NSTAR Electric | Regulatory Tracking Mechanisms    
Regulatory Assets [Line Items]    
Total Regulatory Assets 375,000 376,600
NSTAR Electric | Income Taxes, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 112,800 112,600
NSTAR Electric | Securitized Stranded Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 0 0
NSTAR Electric | Goodwill-related    
Regulatory Assets [Line Items]    
Total Regulatory Assets 252,100 255,700
NSTAR Electric | Derivative Liabilities    
Regulatory Assets [Line Items]    
Total Regulatory Assets 0 0
NSTAR Electric | Asset Retirement Obligations    
Regulatory Assets [Line Items]    
Total Regulatory Assets 61,900 59,800
NSTAR Electric | Other Regulatory Assets    
Regulatory Assets [Line Items]    
Total Regulatory Assets 35,400 37,700
PSNH    
Regulatory Assets [Line Items]    
Total Regulatory Assets 779,200 786,400
Less:  Current Portion 124,701 107,169
Total Long-Term Regulatory Assets 654,507 679,182
PSNH | Benefit Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 116,500 118,900
PSNH | Storm Costs, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 64,200 65,800
PSNH | Regulatory Tracking Mechanisms    
Regulatory Assets [Line Items]    
Total Regulatory Assets 97,000 85,400
PSNH | Income Taxes, Net    
Regulatory Assets [Line Items]    
Total Regulatory Assets 14,500 17,500
PSNH | Securitized Stranded Costs    
Regulatory Assets [Line Items]    
Total Regulatory Assets 468,100 478,900
PSNH | Goodwill-related    
Regulatory Assets [Line Items]    
Total Regulatory Assets 0 0
PSNH | Derivative Liabilities    
Regulatory Assets [Line Items]    
Total Regulatory Assets 0 0
PSNH | Asset Retirement Obligations    
Regulatory Assets [Line Items]    
Total Regulatory Assets 4,200 4,100
PSNH | Other Regulatory Assets    
Regulatory Assets [Line Items]    
Total Regulatory Assets $ 14,700 $ 15,800
v3.22.1
REGULATORY ACCOUNTING - Narrative (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Regulatory Assets [Line Items]    
Amount of regulatory costs not yet approved $ 262.5 $ 252.5
COVID-19    
Regulatory Assets [Line Items]    
Net incremental deferred costs 35.0 33.0
CL&P    
Regulatory Assets [Line Items]    
Amount of regulatory costs not yet approved 113.4 114.9
CL&P | COVID-19    
Regulatory Assets [Line Items]    
Net incremental deferred costs 15.3 18.0
NSTAR Electric    
Regulatory Assets [Line Items]    
Amount of regulatory costs not yet approved 84.2 85.0
NSTAR Electric | COVID-19    
Regulatory Assets [Line Items]    
Net incremental deferred costs 6.1 6.1
PSNH    
Regulatory Assets [Line Items]    
Amount of regulatory costs not yet approved $ 3.4 $ 3.4
v3.22.1
REGULATORY ACCOUNTING - Components of Regulatory Liabilities (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities $ 4,547,200 $ 4,468,700
Less:  Current Portion 652,358 602,432
Total Long-Term Regulatory Liabilities 3,894,768 3,866,251
EDIT due to Tax Cuts and Jobs Act of 2017    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 2,665,700 2,685,200
Cost of Removal    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 667,200 649,600
Regulatory Tracking Mechanisms    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 571,800 448,400
Benefit Costs    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 128,300 133,500
AFUDC - Transmission    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 85,100 81,000
CL&P Settlement Agreement and Storm Performance Penalty    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 12,900 81,300
Other Regulatory Liabilities    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 416,200 389,700
CL&P    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 1,459,900 1,459,800
Less:  Current Portion 251,555 266,489
Total Long-Term Regulatory Liabilities 1,208,297 1,193,259
CL&P | EDIT due to Tax Cuts and Jobs Act of 2017    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 992,700 996,100
CL&P | Cost of Removal    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 108,600 100,100
CL&P | Regulatory Tracking Mechanisms    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 226,700 182,000
CL&P | Benefit Costs    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 0 0
CL&P | AFUDC - Transmission    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 44,000 43,200
CL&P | CL&P Settlement Agreement and Storm Performance Penalty    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 12,900 81,300
CL&P | Other Regulatory Liabilities    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 75,000 57,100
NSTAR Electric    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 1,850,300 1,787,300
Less:  Current Portion 279,299 228,248
Total Long-Term Regulatory Liabilities 1,570,969 1,559,072
NSTAR Electric | EDIT due to Tax Cuts and Jobs Act of 2017    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 973,300 984,500
NSTAR Electric | Cost of Removal    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 388,200 381,000
NSTAR Electric | Regulatory Tracking Mechanisms    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 237,200 185,100
NSTAR Electric | Benefit Costs    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 103,100 107,400
NSTAR Electric | AFUDC - Transmission    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 41,100 37,800
NSTAR Electric | CL&P Settlement Agreement and Storm Performance Penalty    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 0 0
NSTAR Electric | Other Regulatory Liabilities    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 107,400 91,500
PSNH    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 495,200 501,600
Less:  Current Portion 106,393 120,176
Total Long-Term Regulatory Liabilities 388,838 381,366
PSNH | EDIT due to Tax Cuts and Jobs Act of 2017    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 356,100 359,200
PSNH | Cost of Removal    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 19,100 17,200
PSNH | Regulatory Tracking Mechanisms    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 94,900 107,000
PSNH | Benefit Costs    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 0 0
PSNH | AFUDC - Transmission    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 0 0
PSNH | CL&P Settlement Agreement and Storm Performance Penalty    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities 0 0
PSNH | Other Regulatory Liabilities    
Regulatory Liabilities [Line Items]    
Total Regulatory Liabilities $ 25,100 $ 18,200
v3.22.1
PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION - Summary of Property, Plant, and Equipment (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Public Utility, Property, Plant and Equipment [Line Items]    
Distribution - Electric $ 17,809,000 $ 17,679,100
Distribution - Natural Gas 6,713,700 6,694,800
Transmission - Electric 13,011,000 12,882,400
Distribution - Water 1,924,900 1,900,900
Solar 200,900 200,900
Utility 39,659,500 39,358,100
Other 1,509,600 1,469,500
Property, Plant and Equipment, Gross 41,169,100 40,827,600
Less:  Accumulated Depreciation    
Utility    (8,976,200) (8,885,200)
Other (609,800) (580,100)
Total Accumulated Depreciation (9,586,000) (9,465,300)
Property, Plant and Equipment, Net 31,583,100 31,362,300
Construction Work in Progress 2,269,500 2,015,400
Total Property, Plant and Equipment, Net 33,852,596 33,377,650
CL&P    
Public Utility, Property, Plant and Equipment [Line Items]    
Distribution - Electric 7,188,900 7,117,600
Transmission - Electric 5,912,500 5,859,000
Solar 0 0
Property, Plant and Equipment, Gross 13,101,400 12,976,600
Less:  Accumulated Depreciation    
Total Accumulated Depreciation (2,592,600) (2,572,100)
Property, Plant and Equipment, Net 10,508,800 10,404,500
Construction Work in Progress 432,200 399,000
Total Property, Plant and Equipment, Net 10,941,005 10,803,543
NSTAR Electric    
Public Utility, Property, Plant and Equipment [Line Items]    
Distribution - Electric 8,151,100 8,105,500
Transmission - Electric 5,137,100 5,090,500
Solar 200,900 200,900
Property, Plant and Equipment, Gross 13,489,100 13,396,900
Less:  Accumulated Depreciation    
Total Accumulated Depreciation (3,271,800) (3,227,300)
Property, Plant and Equipment, Net 10,217,300 10,169,600
Construction Work in Progress 791,600 707,000
Total Property, Plant and Equipment, Net 11,008,899 10,876,614
PSNH    
Public Utility, Property, Plant and Equipment [Line Items]    
Distribution - Electric 2,509,300 2,496,200
Transmission - Electric 1,963,100 1,934,600
Solar 0 0
Property, Plant and Equipment, Gross 4,472,400 4,430,800
Less:  Accumulated Depreciation    
Total Accumulated Depreciation (912,800) (908,400)
Property, Plant and Equipment, Net 3,559,600 3,522,400
Construction Work in Progress 163,000 134,100
Total Property, Plant and Equipment, Net $ 3,722,618 $ 3,656,462
v3.22.1
DERIVATIVE INSTRUMENTS - Gross Fair Values and Net Amounts of Contracts (Details) - CL&P - Level 3 - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Current Derivative Assets    
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]    
Commodity Supply and Price Risk Management $ 14.8 $ 14.7
Netting (0.4) (1.0)
Net Amount Recorded as a Derivative 14.4 13.7
Other Long-Term Assets    
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]    
Commodity Supply and Price Risk Management 41.4 46.9
Netting (1.3) (0.9)
Net Amount Recorded as a Derivative 40.1 46.0
Current Derivative Liabilities    
Current and Long-Term Derivative Liabilities    
Commodity Supply and Price Risk Management (74.4) (73.5)
Netting 0.0 0.0
Net Amount Recorded as a Derivative (74.4) (73.5)
Long-Term Derivative Liabilities    
Current and Long-Term Derivative Liabilities    
Commodity Supply and Price Risk Management (209.5) (235.4)
Netting 0.0 0.0
Net Amount Recorded as a Derivative $ (209.5) $ (235.4)
v3.22.1
DERIVATIVE INSTRUMENTS - Narrative (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
MW
Mar. 31, 2021
USD ($)
Dec. 31, 2021
$ / KWmo
MW
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Percentage of costs or benefits borne under capacity-related contracts by United Illuminated Company 20.00%    
Amount of power to be purchased under capacity-related contract (in MW) | MW 675   675
Gains (losses) on deferred as regulatory costs | $ $ 6.2 $ (11.1)  
Level 3 | Minimum      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Percentage of exit price premiums related to derivative contracts 4.50%    
Level 3 | Maximum      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Percentage of exit price premiums related to derivative contracts 8.80%    
Level 3 | Weighted Average      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Percentage of exit price premiums related to derivative contracts 7.70%    
CL&P      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Percentage of costs or benefits borne under capacity-related contracts 80.00%    
CL&P | Weighted Average | Measurement Input, Capacity Prices      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Derivative measurement input | $ / KWmo     2.61
v3.22.1
DERIVATIVE INSTRUMENTS - Summary of Level 3 Derivative Contracts and Significant Unobservable Inputs Used (Details) - CL&P - Forward Reserve Prices - Level 3 - $ / KWmo
Mar. 31, 2022
Dec. 31, 2021
Minimum    
Derivative Instruments and Hedging Activities Disclosures [Line Items]    
Derivative measurement input 0.50 0.50
Maximum    
Derivative Instruments and Hedging Activities Disclosures [Line Items]    
Derivative measurement input 1.15 1.15
Weighted Average    
Derivative Instruments and Hedging Activities Disclosures [Line Items]    
Derivative measurement input 0.82 0.82
v3.22.1
DERIVATIVE INSTRUMENTS - Changes in the Level 3 Category of Derivative Assets Measured at Fair Value on a Recurring Basis (Details) - CL&P - Level 3 - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Derivatives, Net [Rollforward]    
Fair Value as of Beginning of Period $ (249.2) $ (293.1)
Net Realized/Unrealized Gains/(Losses) Included in Regulatory Assets 6.2 (12.5)
Settlements 13.6 12.5
Fair Value as of End of Period $ (229.4) $ (293.1)
v3.22.1
MARKETABLE SECURITIES - Narrative (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]      
Available-for-sale equity securities $ 31.5   $ 40.2
Unrealized (loss) gain recorded in other income (4.4) $ 1.1  
CYAPC and YAEC      
Debt Securities, Available-for-sale [Line Items]      
Available-for-sale equity securities 195.5   214.0
Marketable securities held in nuclear decommissioning trust $ 183.4   $ 189.9
v3.22.1
MARKETABLE SECURITIES - Summary of Available-for-Sale Debt Securities (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]    
Amortized Cost $ 211.4 $ 214.5
Pre-Tax Unrealized Gains 0.5 5.1
Pre-Tax Unrealized Losses (3.6) (0.2)
Fair Value $ 208.3 $ 219.4
v3.22.1
MARKETABLE SECURITIES - Contractual Maturities of Available-for-Sale Debt Securities (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Amortized Cost    
Less than one year $ 27.0  
One to five years 61.9  
Six to ten years 36.3  
Greater than ten years 86.2  
Amortized Cost 211.4 $ 214.5
Fair Value    
Less than one year 27.0  
One to five years 61.6  
Six to ten years 35.5  
Greater than ten years 84.2  
Fair Value $ 208.3 $ 219.4
v3.22.1
MARKETABLE SECURITIES - Marketable Securities Recorded at Fair Value on a Recurring Basis by Level (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities $ 435.3 $ 473.6
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 253.0 285.5
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 182.3 188.1
Mutual Funds and Equities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 227.0 254.2
Money Market Funds | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 26.0 31.3
U.S. Government Issued Debt Securities (Agency and Treasury) | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 80.0 81.3
Corporate Debt Securities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 62.5 65.3
Asset-Backed Debt Securities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 11.6 12.6
Municipal Bonds | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 11.7 12.3
Other Fixed Income Securities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities $ 16.5 $ 16.6
v3.22.1
SHORT-TERM AND LONG-TERM DEBT - Narrative (Details) - USD ($)
 3 Months Ended
Mar. 31, 2022
Dec. 31, 2021
NSTAR Electric    
Line of Credit Facility [Line Items]    
Notes payable to Eversource parent $ 4,000,000  
PSNH    
Line of Credit Facility [Line Items]    
Notes payable to Eversource parent 196,400,000 $ 110,600,000
Line of Credit | CL&P    
Line of Credit Facility [Line Items]    
Maximum borrowing capacity 450,000,000  
Amount outstanding under line of credit 0  
Line of Credit | PSNH    
Line of Credit Facility [Line Items]    
Maximum borrowing capacity 300,000,000  
Amount outstanding under line of credit 0  
Commercial Paper | NSTAR Electric    
Line of Credit Facility [Line Items]    
Maximum borrowing capacity 650,000,000  
Line of Credit    
Line of Credit Facility [Line Items]    
Amount outstanding under line of credit 0 $ 0
Line of Credit | NSTAR Electric    
Line of Credit Facility [Line Items]    
Maximum borrowing capacity 650,000,000  
Eversource Parent | Commercial Paper    
Line of Credit Facility [Line Items]    
Maximum borrowing capacity 2,000,000,000  
Eversource Parent | Line of Credit    
Line of Credit Facility [Line Items]    
Maximum borrowing capacity $ 2,000,000,000  
Debt instrument term 5 years  
NSTAR Electric | Line of Credit | NSTAR Electric    
Line of Credit Facility [Line Items]    
Debt instrument term 5 years  
v3.22.1
SHORT-TERM AND LONG-TERM DEBT - Borrowings Outstanding and Available under the Commercial Paper Programs (Details) - Commercial Paper - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Debt Instrument [Line Items]    
Borrowings outstanding $ 1,393.8 $ 1,343.0
Available borrowing capacity $ 606.2 $ 657.0
Weighted-average interest rate 0.93% 0.31%
NSTAR Electric    
Debt Instrument [Line Items]    
Borrowings outstanding $ 275.0 $ 162.5
Available borrowing capacity $ 375.0 $ 487.5
Weighted-average interest rate 0.43% 0.14%
v3.22.1
SHORT-TERM AND LONG-TERM DEBT - Summary of Long-Term Debt Issuance and Repayments (Details) - USD ($)
$ in Thousands
 1 Months Ended 3 Months Ended
Mar. 31, 2022
Feb. 28, 2022
Mar. 31, 2022
Mar. 31, 2021
Debt Instrument [Line Items]        
Repayments     $ (770,000) $ (572,000)
Yankee Gas | First Mortgage | Yankee Gas 8.48% Series B First Mortgage Bonds        
Debt Instrument [Line Items]        
Interest rate, stated percentage 8.48%   8.48%  
Repayments $ (20,000)      
Eversource Parent | Senior Notes | Eversource Parent 2.90% Series V Senior Notes        
Debt Instrument [Line Items]        
Interest rate, stated percentage   2.90%    
Issuances   $ 650,000    
Eversource Parent | Senior Notes | Eversource Parent 3.38% Series W Senior Notes        
Debt Instrument [Line Items]        
Interest rate, stated percentage   3.38%    
Issuances   $ 650,000    
Eversource Parent | Senior Notes | Eversource Parent 2.75% Series K Senior Notes        
Debt Instrument [Line Items]        
Interest rate, stated percentage 2.75%   2.75%  
Repayments $ (750,000)      
v3.22.1
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES - Narrative (Details) - PSNH - Rate Reduction Bonds
May 31, 2018
USD ($)
Debt Instrument [Line Items]  
Amount of securitized rate reduction bonds issued $ 635,700,000
Weighted average interest rate 3.66%
v3.22.1
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES - Summary of the Impact of Funding on the Balance Sheets (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Condensed Balance Sheet Statements, Captions [Line Items]    
Securitized Stranded Cost (included in Regulatory Assets) $ 5,701,400 $ 5,715,800
Regulatory Liabilities 3,894,768 3,866,251
Accrued Interest (included in Other Current Liabilities) 925,467 830,620
Rate Reduction Bonds - Current Portion 43,210 43,210
Rate Reduction Bonds - Long-Term Portion 432,097 453,702
Securitized Stranded Costs    
Condensed Balance Sheet Statements, Captions [Line Items]    
Securitized Stranded Cost (included in Regulatory Assets) 468,100 478,900
Other Regulatory Assets    
Condensed Balance Sheet Statements, Captions [Line Items]    
Securitized Stranded Cost (included in Regulatory Assets) 162,100 150,000
Current Derivative Assets    
Condensed Balance Sheet Statements, Captions [Line Items]    
Restricted Cash 73,300 78,200
Other Long-Term Assets    
Condensed Balance Sheet Statements, Captions [Line Items]    
Restricted Cash 19,100 44,700
PSNH    
Condensed Balance Sheet Statements, Captions [Line Items]    
Securitized Stranded Cost (included in Regulatory Assets) 779,200 786,400
Regulatory Liabilities 388,838 381,366
Accrued Interest (included in Other Current Liabilities) 64,356 63,005
Rate Reduction Bonds - Current Portion 43,210 43,210
Rate Reduction Bonds - Long-Term Portion 432,097 453,702
PSNH | VIE    
Condensed Balance Sheet Statements, Captions [Line Items]    
Rate Reduction Bonds - Current Portion 43,200 43,200
Rate Reduction Bonds - Long-Term Portion 432,100 453,700
PSNH | Securitized Stranded Costs    
Condensed Balance Sheet Statements, Captions [Line Items]    
Securitized Stranded Cost (included in Regulatory Assets) 468,100 478,900
PSNH | Securitized Stranded Costs | VIE    
Condensed Balance Sheet Statements, Captions [Line Items]    
Securitized Stranded Cost (included in Regulatory Assets) 468,100 478,900
PSNH | Other Regulatory Assets    
Condensed Balance Sheet Statements, Captions [Line Items]    
Securitized Stranded Cost (included in Regulatory Assets) 14,700 15,800
PSNH | Other Regulatory Assets | VIE    
Condensed Balance Sheet Statements, Captions [Line Items]    
Regulatory Liabilities 6,000 5,400
Accrued Interest (included in Other Current Liabilities) 2,900 7,500
PSNH | Current Derivative Assets    
Condensed Balance Sheet Statements, Captions [Line Items]    
Restricted Cash 16,600 31,400
PSNH | Current Derivative Assets | VIE    
Condensed Balance Sheet Statements, Captions [Line Items]    
Restricted Cash 16,300 31,100
PSNH | Other Long-Term Assets    
Condensed Balance Sheet Statements, Captions [Line Items]    
Restricted Cash 3,200 3,200
PSNH | Other Long-Term Assets | VIE    
Condensed Balance Sheet Statements, Captions [Line Items]    
Restricted Cash $ 3,200 $ 3,200
v3.22.1
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES - Summary of the Impact of Funding on the Income Statements (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Condensed Income Statements, Captions [Line Items]    
Interest Expense on RRB Principal (included in Interest Expense) $ 153,245 $ 137,766
PSNH    
Condensed Income Statements, Captions [Line Items]    
Amortization of RRB Principal (included in Amortization of Regulatory Assets, Net) (26,834) (18,547)
Interest Expense on RRB Principal (included in Interest Expense) 13,645 14,630
PSNH | VIE | Rate Reduction Bonds    
Condensed Income Statements, Captions [Line Items]    
Amortization of RRB Principal (included in Amortization of Regulatory Assets, Net) 10,800 10,800
Interest Expense on RRB Principal (included in Interest Expense) $ 4,400 $ 4,700
v3.22.1
PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION - Components of Net Periodic Benefit Expense/(Income) (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Pension and SERP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost $ 17.7 $ 21.3
Interest Cost 38.6 32.6
Expected Return on Plan Assets (131.7) (108.9)
Actuarial Loss 30.7 61.6
Prior Service Cost/(Credit) 0.4 0.3
Total Net Periodic Benefit Plan Expense/(Income) (44.3) 6.9
PBOP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost 2.8 3.5
Interest Cost 5.0 4.4
Expected Return on Plan Assets (22.4) (19.7)
Actuarial Loss 0.0 2.6
Prior Service Cost/(Credit) (5.4) (5.3)
Total Net Periodic Benefit Plan Expense/(Income) (20.0) (14.5)
CL&P | Pension and SERP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost 4.5 6.3
Interest Cost 7.8 7.3
Expected Return on Plan Assets (26.6) (21.6)
Actuarial Loss 4.2 13.0
Prior Service Cost/(Credit) 0.0 0.0
Total Net Periodic Benefit Plan Expense/(Income) (10.1) 5.0
Intercompany Expense/(Income) Allocations (3.8) 1.3
CL&P | PBOP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost 0.5 0.6
Interest Cost 0.9 0.8
Expected Return on Plan Assets (2.8) (2.6)
Actuarial Loss 0.0 0.4
Prior Service Cost/(Credit) 0.2 0.2
Total Net Periodic Benefit Plan Expense/(Income) (1.2) (0.6)
Intercompany Expense/(Income) Allocations (0.9) (0.3)
NSTAR Electric | Pension and SERP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost 3.6 4.0
Interest Cost 8.1 6.7
Expected Return on Plan Assets (32.0) (26.9)
Actuarial Loss 8.5 15.5
Prior Service Cost/(Credit) 0.1 0.1
Total Net Periodic Benefit Plan Expense/(Income) (11.7) (0.6)
Intercompany Expense/(Income) Allocations (2.9) 1.5
NSTAR Electric | PBOP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost 0.5 0.6
Interest Cost 1.3 1.1
Expected Return on Plan Assets (10.6) (9.3)
Actuarial Loss 0.0 0.6
Prior Service Cost/(Credit) (4.3) (4.2)
Total Net Periodic Benefit Plan Expense/(Income) (13.1) (11.2)
Intercompany Expense/(Income) Allocations (0.9) (0.4)
PSNH | Pension and SERP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost 1.8 2.2
Interest Cost 4.2 3.6
Expected Return on Plan Assets (14.1) (11.9)
Actuarial Loss 2.2 4.9
Prior Service Cost/(Credit) 0.0 0.0
Total Net Periodic Benefit Plan Expense/(Income) (5.9) (1.2)
Intercompany Expense/(Income) Allocations (0.8) 0.5
PSNH | PBOP    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service Cost 0.2 0.3
Interest Cost 0.5 0.5
Expected Return on Plan Assets (1.6) (1.5)
Actuarial Loss 0.0 0.3
Prior Service Cost/(Credit) 0.1 0.1
Total Net Periodic Benefit Plan Expense/(Income) (0.8) (0.3)
Intercompany Expense/(Income) Allocations $ (0.3) $ (0.1)
v3.22.1
PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION - Narrative (Details)
$ in Millions
Mar. 31, 2022
USD ($)
PBOP  
Defined Benefit Plan Disclosure [Line Items]  
Expected pension plan contributions $ 2.4
Minimum  
Defined Benefit Plan Disclosure [Line Items]  
Expected pension plan contributions 100.0
Maximum  
Defined Benefit Plan Disclosure [Line Items]  
Expected pension plan contributions $ 175.0
v3.22.1
COMMITMENTS AND CONTINGENCIES - Environmental Sites and Related Reserves (Details)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2022
USD ($)
site
Dec. 31, 2021
USD ($)
site
Site Contingency [Line Items]    
Number of Sites | site 61 61
Reserve | $ $ 117.8 $ 115.4
CL&P    
Site Contingency [Line Items]    
Number of Sites | site 14 14
Reserve | $ $ 14.3 $ 13.9
NSTAR Electric    
Site Contingency [Line Items]    
Number of Sites | site 11 11
Reserve | $ $ 3.2 $ 3.3
PSNH    
Site Contingency [Line Items]    
Number of Sites | site 9 9
Reserve | $ $ 6.4 $ 6.3
v3.22.1
COMMITMENTS AND CONTINGENCIES - Environmental Matters (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Site Contingency [Line Items]    
Reserve balance $ 117.8 $ 115.4
MGP Sites    
Site Contingency [Line Items]    
Reserve balance $ 108.3 $ 105.6
v3.22.1
COMMITMENTS AND CONTINGENCIES - Non-Cancellable Commitments under Purchase Commitment Contracts (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
megawatt
Offshore Wind Project  
Unrecorded Unconditional Purchase Obligation [Line Items]  
Contract term 20 years
Energy capacity (in MW) | megawatt 800
Renewable Energy | NSTAR Electric  
Unrecorded Unconditional Purchase Obligation [Line Items]  
2022 $ 75.6
2023 78.3
2024 269.4
2025 315.8
2026 322.1
Thereafter 5,812.2
Total 6,873.4
Renewable Energy | NSTAR Electric | Massachusetts Clean Energy 83D Contract  
Unrecorded Unconditional Purchase Obligation [Line Items]  
Total $ 6,000.0
Contract term 20 years
Renewable Energy | NSTAR Electric | Minimum | Massachusetts Clean Energy 83D Contract  
Unrecorded Unconditional Purchase Obligation [Line Items]  
Estimated costs $ 240.0
Renewable Energy | NSTAR Electric | Maximum | Massachusetts Clean Energy 83D Contract  
Unrecorded Unconditional Purchase Obligation [Line Items]  
Estimated costs $ 375.0
v3.22.1
COMMITMENTS AND CONTINGENCIES - Guarantees and Obligations Narrative (Details) - USD ($)
Apr. 30, 2022
Mar. 31, 2022
Jan. 31, 2022
Dec. 31, 2021
Sep. 16, 2020
Loss Contingencies [Line Items]          
Fair value of guarantees   $ 7,000,000   $ 7,300,000  
Letter of Credit | South Fork Wind, LLC          
Loss Contingencies [Line Items]          
Amount outstanding under line of credit     $ 4,300,000    
Letter of Credit | Eversource Investment LLC          
Loss Contingencies [Line Items]          
Maximum borrowing capacity         $ 25,000,000
Subsequent Event | Letter of Credit | South Fork Wind, LLC          
Loss Contingencies [Line Items]          
Amount outstanding under line of credit $ 160,200,000        
v3.22.1
COMMITMENTS AND CONTINGENCIES - Guarantees and Indemnifications (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Oct. 23, 2019
Jan. 25, 2017
North East Offshore LLC      
Guarantor Obligations [Line Items]      
Ownership interest 50.00%    
Sunrise Wind LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 420.6    
Ownership interest 50.00%    
Revolution Wind, LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 268.5    
Ownership interest 50.00%    
South Fork Wind, LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 184.0    
Eversource Investment LLC | North East Offshore LLC      
Guarantor Obligations [Line Items]      
Ownership interest 50.00%    
Construction-related purchase agreements with third-party contractors | South Fork Wind, LLC      
Guarantor Obligations [Line Items]      
Ownership interest 50.00%    
Construction-related purchase agreements with third-party contractors | North East Offshore LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 936.3    
Construction-related purchase agreements with third-party contractors | Sunrise Wind LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 330.6    
Construction-related purchase agreements with third-party contractors | Revolution Wind, LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 254.7    
Construction-related purchase agreements with third-party contractors | South Fork Wind, LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 165.3    
Funding and indemnification obligations of North East Offshore LLC | Eversource Investment LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 107.8    
Funding and indemnification obligations of North East Offshore LLC | Eversource Investment LLC | North East Offshore LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 910.0    
Power Purchase Agreement | South Fork Wind, LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 7.1   $ 7.1
Ownership interest 50.00%    
OREC capacity production | Sunrise Wind LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 2.2 $ 15.4  
Ownership interest 50.00%    
Real estate purchase | Bay State Wind LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 2.5    
Transmission interconnection | South Fork Wind, LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 1.2    
Letter of Credit | Eversource Investment LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 4.3    
Surety bonds | Various      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 35.0    
Lease payments for real estate | Eversource Service      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) 0.7    
Performance guarantee | North East Offshore LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 1,300.0    
Percent of obligations guaranteed 50.00%    
Payment guarantee | North East Offshore LLC      
Guarantor Obligations [Line Items]      
Maximum exposure (up to) $ 62.5    
Percent of obligations guaranteed 50.00%    
v3.22.1
COMMITMENTS AND CONTINGENCIES - Spent Nuclear Fuel Obligations - Yankee Companies (Details)
$ in Millions
Mar. 25, 2021
USD ($)
CYAPC, YAEC, and MYAPC | Yankee Companies  
Loss Contingencies [Line Items]  
Damages sought $ 120.4
v3.22.1
COMMITMENTS AND CONTINGENCIES - FERC ROE Complaints (Details)
$ in Millions
 3 Months Ended 36 Months Ended
Apr. 29, 2016
complaint
Oct. 16, 2014
Mar. 31, 2022
USD ($)
Oct. 15, 2014
Dec. 31, 2021
USD ($)
Oct. 16, 2018
complaint
Jul. 31, 2014
complaint
Loss Contingencies [Line Items]              
Percentage of base ROE reasonably justified     10.41%        
Percentage of incentive cap on total ROE     13.08%        
FERC ROE Complaints              
Loss Contingencies [Line Items]              
Number of complaints filed | complaint 4         4  
Period of complaint     15 months        
Basis point change     0.10%        
Estimate of possible loss for each 10 basis point change to base ROE     $ 3.0        
FERC ROE First, Second and Third Complaints              
Loss Contingencies [Line Items]              
Number of complaints filed | complaint             3
Base ROE subsequently authorized     11.14%        
FERC ROE First, Second and Third Complaints | Minimum              
Loss Contingencies [Line Items]              
Percentage of maximum ROE for any incentive project       11.14%      
FERC ROE First, Second and Third Complaints | Maximum              
Loss Contingencies [Line Items]              
Percentage of maximum ROE for any incentive project       13.10%      
FERC ROE Fourth Complaint              
Loss Contingencies [Line Items]              
Base ROE percentage of complaint period 10.57%            
Maximum percentage cap of ROE for incentive projects 11.74%            
FERC ROE First Complaint              
Loss Contingencies [Line Items]              
Base ROE subsequently authorized   10.57%          
Percentage of maximum ROE for any incentive project   11.74%          
Amounts associated with first complaint refunded     $ 38.9        
FERC ROE First Complaint | CL&P              
Loss Contingencies [Line Items]              
Amounts associated with first complaint refunded     22.4        
FERC ROE First Complaint | NSTAR Electric              
Loss Contingencies [Line Items]              
Amounts associated with first complaint refunded     13.7        
FERC ROE First Complaint | PSNH              
Loss Contingencies [Line Items]              
Amounts associated with first complaint refunded     $ 2.8        
FERC ROE Second Complaint              
Loss Contingencies [Line Items]              
Base ROE percentage of complaint period     10.57%        
Percentage of maximum ROE for any incentive project     11.74%        
Loss contingency, estimate of possible earnings impact     $ 39.1   $ 39.1    
FERC ROE Second Complaint | CL&P              
Loss Contingencies [Line Items]              
Loss contingency, estimate of possible earnings impact     21.4   21.4    
FERC ROE Second Complaint | NSTAR Electric              
Loss Contingencies [Line Items]              
Loss contingency, estimate of possible earnings impact     14.6   14.6    
FERC ROE Second Complaint | PSNH              
Loss Contingencies [Line Items]              
Loss contingency, estimate of possible earnings impact     $ 3.1   $ 3.1    
v3.22.1
COMMITMENTS AND CONTINGENCIES - Eversource and NSTAR Electric Boston Harbor Civil Action (Details)
Jul. 15, 2016
kV
Commitments and Contingencies Disclosure [Abstract]  
Amount of capacity required for installation of distribution cable (in kV) 115
v3.22.1
COMMITMENTS AND CONTINGENCIES - CL&P Tropical Storm Isaias Response Investigation (Details) - USD ($)
$ / shares in Units, $ in Millions
Jul. 14, 2021
May 07, 2021
May 06, 2021
Apr. 28, 2021
Loss Contingencies [Line Items]        
Loss contingency, allowed rate of ROE       9.25%
Unfavorable Regulatory Action        
Loss Contingencies [Line Items]        
Loss contingency, estimate of possible earnings impact     $ 30.0  
Loss contingency, estimate of possible earnings impact, non-compliance with performance standards     28.4  
Loss contingency, estimate of possible earnings impact, accident reporting violation fines     $ 1.6  
Non-compliance fine $ 28.6      
Loss contingency, accident reporting violation fines $ 0.2      
Loss contingency, penalty rate as a percent of distribution revenues   2.50%    
Loss contingency, after-tax earnings impact per share (in dollars per share) $ 0.07      
v3.22.1
FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption $ 155,570 $ 155,570
Rate Reduction Bonds 432,097 453,702
Carrying Amount    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 155,600 155,600
Long-Term Debt 18,729,600 18,216,700
Rate Reduction Bonds 475,300 496,900
Fair Value | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 158,300 166,300
Long-Term Debt 18,562,300 19,636,300
Rate Reduction Bonds 492,800 543,300
CL&P    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 116,200 116,200
CL&P | Carrying Amount    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 116,200 116,200
Long-Term Debt 4,215,700 4,215,400
Rate Reduction Bonds 0 0
CL&P | Fair Value | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 115,500 122,300
Long-Term Debt 4,392,200 4,848,900
Rate Reduction Bonds 0 0
NSTAR Electric    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 43,000 43,000
NSTAR Electric | Carrying Amount    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 43,000 43,000
Long-Term Debt 3,986,300 3,985,400
Rate Reduction Bonds 0 0
NSTAR Electric | Fair Value | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 42,800 44,000
Long-Term Debt 4,094,100 4,453,500
Rate Reduction Bonds 0 0
PSNH    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Rate Reduction Bonds 432,097 453,702
PSNH | Carrying Amount    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 0 0
Long-Term Debt 1,164,000 1,163,800
Rate Reduction Bonds 475,300 496,900
PSNH | Fair Value | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Preferred Stock Not Subject to Mandatory Redemption 0 0
Long-Term Debt 1,086,300 1,220,600
Rate Reduction Bonds $ 492,800 $ 543,300
v3.22.1
ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
AOCI Attributable to Parent [Roll Forward]    
OCI Before Reclassifications $ (800) $ (700)
Amounts Reclassified from AOCI 1,500 1,900
Net OCI 704 1,188
Accumulated Other Comprehensive Loss    
AOCI Attributable to Parent [Roll Forward]    
Beginning balance (42,300) (76,400)
Net OCI 704 1,188
Ending balance (41,600) (75,200)
Qualified Cash Flow Hedging Instruments    
AOCI Attributable to Parent [Roll Forward]    
Beginning balance (400) (1,400)
OCI Before Reclassifications 0 0
Amounts Reclassified from AOCI 0 400
Net OCI 0 400
Ending balance (400) (1,000)
Unrealized Gains/(Losses) on Marketable Securities    
AOCI Attributable to Parent [Roll Forward]    
Beginning balance 400 1,100
OCI Before Reclassifications (800) (700)
Amounts Reclassified from AOCI 0 0
Net OCI (800) (700)
Ending balance (400) 400
Defined Benefit Plans    
AOCI Attributable to Parent [Roll Forward]    
Beginning balance (42,300) (76,100)
OCI Before Reclassifications 0 0
Amounts Reclassified from AOCI 1,500 1,500
Net OCI 1,500 1,500
Ending balance $ (40,800) $ (74,600)
v3.22.1
COMMON SHARES - Common Shares Authorized and Issued (Details) - $ / shares
Mar. 31, 2022
Dec. 31, 2021
Class of Stock [Line Items]    
Par value (in dollars per share) $ 5  
Authorized (in shares) 380,000,000 380,000,000
Issued (in shares) 357,818,402 357,818,402
CL&P    
Class of Stock [Line Items]    
Par value (in dollars per share) $ 10  
Authorized (in shares) 24,500,000 24,500,000
Issued (in shares) 6,035,205 6,035,205
NSTAR Electric    
Class of Stock [Line Items]    
Par value (in dollars per share) $ 1  
Authorized (in shares) 100,000,000 100,000,000
Issued (in shares) 200 200
PSNH    
Class of Stock [Line Items]    
Par value (in dollars per share) $ 1  
Authorized (in shares) 100,000,000 100,000,000
Issued (in shares) 301 301
v3.22.1
COMMON SHARES - Narrative (Details) - shares
Mar. 31, 2022
Dec. 31, 2021
Equity [Abstract]    
Treasury stock (in shares) 12,968,130 13,415,206
Common stock outstanding (in shares) 344,850,272 344,403,196
v3.22.1
COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Equity [Abstract]      
Dividends on preferred stock $ 1,880 $ 1,880  
Noncontrolling interest attributed to preferred stock of subsidiaries $ 155,570   $ 155,570
v3.22.1
EARNINGS PER SHARE - Narrative (Details)
shares in Thousands
 3 Months Ended
Mar. 31, 2022
shares
Earnings Per Share [Abstract]  
Antidilutive share awards excluded from the EPS computation (in shares) 0
v3.22.1
EARNINGS PER SHARE - Components of Basic and Diluted EPS (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Earnings Per Share [Abstract]    
Net Income Attributable to Common Shareholders $ 443,446 $ 366,143
Net Income Attributable to Common Shareholders $ 443,400 $ 366,100
Weighted Average Common Shares Outstanding:    
Basic (in shares) 345,156,346 343,678,243
Share-Based Compensation Awards and Other (in shares) 504,787 656,446
Diluted (in shares) 345,661,133 344,334,689
Basic EPS (in dollars per share) $ 1.28 $ 1.07
Diluted EPS (in dollars per share) $ 1.28 $ 1.06
v3.22.1
REVENUES (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Sep. 01, 2021
May 06, 2021
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers $ 3,452,000 $ 2,771,700      
Alternative Revenue Programs 15,800 52,500      
Other Revenues 3,500 1,600      
Operating Revenues 3,471,310 2,825,840      
(Customer Credits)/Reserve at CL&P related to PURA Settlement Agreement and Storm Performance Penalty $ (58,412) $ 30,000      
Operating Lease, Income, Comprehensive Income [Extensible Enumeration] Operating Revenues Operating Revenues      
Lease revenue $ 1,000 $ 1,600      
Unfavorable Regulatory Action          
Disaggregation of Revenue [Line Items]          
Loss contingency, estimate of possible earnings impact, non-compliance with performance standards         $ 28,400
CL&P          
Disaggregation of Revenue [Line Items]          
Operating Revenues 1,285,831 987,274      
(Customer Credits)/Reserve at CL&P related to PURA Settlement Agreement and Storm Performance Penalty $ (58,412) $ 30,000      
Operating Lease, Income, Comprehensive Income [Extensible Enumeration] Operating Revenues Operating Revenues      
Lease revenue $ 200 $ 200      
CL&P | Unfavorable Regulatory Action          
Disaggregation of Revenue [Line Items]          
Loss contingency, estimate of possible earnings impact, non-compliance with performance standards       $ 28,400  
CL&P | Unfavorable Regulatory Action | Sales          
Disaggregation of Revenue [Line Items]          
(Customer Credits)/Reserve at CL&P related to PURA Settlement Agreement and Storm Performance Penalty 65,000        
NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Operating Revenues $ 863,176 $ 737,043      
Operating Lease, Income, Comprehensive Income [Extensible Enumeration] Operating Revenues Operating Revenues      
Lease revenue $ 600 $ 1,100      
PSNH          
Disaggregation of Revenue [Line Items]          
Operating Revenues $ 339,427 $ 293,435      
Operating Lease, Income, Comprehensive Income [Extensible Enumeration] Operating Revenues Operating Revenues      
Total Retail Tariff Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers $ 2,857,900 $ 2,476,300      
Residential          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,771,200 1,560,000      
Commercial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 932,400 779,900      
Industrial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 154,300 136,400      
Wholesale Transmission Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 105,900 92,500      
Wholesale Market Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 399,800 176,300      
Other Revenues from Contracts with Customers          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 30,400 26,600      
(Reserve for)/Amortization of Revenues Subject to Refund          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 58,000        
Operating Segments | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,430,100 1,102,700      
Alternative Revenue Programs 1,300 8,900      
Other Revenues 100 200      
Operating Segments | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,004,700 838,500      
Alternative Revenue Programs (8,200) 13,800      
Other Revenues 2,000 1,100      
Operating Segments | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 395,100 333,700      
Alternative Revenue Programs (3,300) 3,000      
Other Revenues 900 0      
Operating Segments | Total Retail Tariff Sales Revenues | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 874,800 796,700      
Operating Segments | Total Retail Tariff Sales Revenues | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 770,000 655,300      
Operating Segments | Total Retail Tariff Sales Revenues | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 292,900 257,300      
Operating Segments | Residential | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 599,100 545,800      
Operating Segments | Residential | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 404,600 362,400      
Operating Segments | Residential | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 182,500 157,800      
Operating Segments | Commercial | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 242,200 214,200      
Operating Segments | Commercial | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 331,300 268,300      
Operating Segments | Commercial | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 88,400 77,800      
Operating Segments | Industrial | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 33,500 36,700      
Operating Segments | Industrial | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 34,100 24,600      
Operating Segments | Industrial | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 22,000 21,700      
Operating Segments | Wholesale Transmission Revenues | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 209,100 189,000      
Operating Segments | Wholesale Transmission Revenues | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 165,200 147,100      
Operating Segments | Wholesale Transmission Revenues | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 71,900 58,200      
Operating Segments | Wholesale Market Sales Revenues | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 279,900 109,700      
Operating Segments | Wholesale Market Sales Revenues | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 57,900 24,400      
Operating Segments | Wholesale Market Sales Revenues | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 27,700 15,000      
Operating Segments | Other Revenues from Contracts with Customers | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 7,900 7,300      
Operating Segments | Other Revenues from Contracts with Customers | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 11,600 11,700      
Operating Segments | Other Revenues from Contracts with Customers | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 2,600 3,200      
Operating Segments | (Reserve for)/Amortization of Revenues Subject to Refund | CL&P          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 58,400 0      
Operating Segments | (Reserve for)/Amortization of Revenues Subject to Refund | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Operating Segments | (Reserve for)/Amortization of Revenues Subject to Refund | PSNH          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Operating Segments | Reserves For Revenues Subject To Refund | CL&P | Unfavorable Regulatory Action          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers     $ 93,400    
Other          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 383,500 343,000      
Alternative Revenue Programs 0 0      
Other Revenues 0 0      
Operating Revenues 383,500 343,000      
Other | Total Retail Tariff Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Other | Residential          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Other | Commercial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Other | Industrial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Other | Wholesale Transmission Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 24,400 19,200      
Other | Wholesale Market Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Other | Other Revenues from Contracts with Customers          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 359,100 323,800      
Other | (Reserve for)/Amortization of Revenues Subject to Refund          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0        
Eliminations          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers (723,400) (647,200)      
Alternative Revenue Programs 13,600 2,200      
Other Revenues 0 0      
Operating Revenues (709,800) (645,000)      
Eliminations | Total Retail Tariff Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers (5,600) (4,900)      
Eliminations | Residential          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Eliminations | Commercial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers (1,100) (1,400)      
Eliminations | Industrial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers (4,500) (3,500)      
Eliminations | Wholesale Transmission Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers (364,700) (321,000)      
Eliminations | Wholesale Market Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Eliminations | Other Revenues from Contracts with Customers          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers (353,100) (321,300)      
Eliminations | (Reserve for)/Amortization of Revenues Subject to Refund          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0        
Eliminations | CL&P          
Disaggregation of Revenue [Line Items]          
Operating Revenues (145,700) (124,500)      
Eliminations | NSTAR Electric          
Disaggregation of Revenue [Line Items]          
Operating Revenues (135,300) (116,400)      
Eliminations | PSNH          
Disaggregation of Revenue [Line Items]          
Operating Revenues (53,300) (43,300)      
Electric Distribution | Operating Segments          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 2,378,700 1,876,200      
Alternative Revenue Programs 4,800 23,000      
Other Revenues 2,800 1,100      
Operating Revenues 2,386,300 1,900,300      
Electric Distribution | Operating Segments | Total Retail Tariff Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,937,100 1,708,900      
Electric Distribution | Operating Segments | Residential          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,186,200 1,066,000      
Electric Distribution | Operating Segments | Commercial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 661,300 559,900      
Electric Distribution | Operating Segments | Industrial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 89,600 83,000      
Electric Distribution | Operating Segments | Wholesale Transmission Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Electric Distribution | Operating Segments | Wholesale Market Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 365,500 149,100      
Electric Distribution | Operating Segments | Other Revenues from Contracts with Customers          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 17,700 18,200      
Electric Distribution | Operating Segments | (Reserve for)/Amortization of Revenues Subject to Refund          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 58,400        
Natural Gas Distribution | Operating Segments          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 917,000 757,500      
Alternative Revenue Programs 10,200 22,800      
Other Revenues 400 200      
Operating Revenues 927,600 780,500      
Natural Gas Distribution | Operating Segments | Total Retail Tariff Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 882,500 729,800      
Natural Gas Distribution | Operating Segments | Residential          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 556,800 466,300      
Natural Gas Distribution | Operating Segments | Commercial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 257,600 207,600      
Natural Gas Distribution | Operating Segments | Industrial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 68,100 55,900      
Natural Gas Distribution | Operating Segments | Wholesale Transmission Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Natural Gas Distribution | Operating Segments | Wholesale Market Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 33,500 26,400      
Natural Gas Distribution | Operating Segments | Other Revenues from Contracts with Customers          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,000 1,300      
Natural Gas Distribution | Operating Segments | (Reserve for)/Amortization of Revenues Subject to Refund          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0        
Electric Transmission | Operating Segments          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 450,000 397,700      
Alternative Revenue Programs (15,000) 2,700      
Other Revenues 200 200      
Operating Revenues 435,200 400,600      
Electric Transmission | Operating Segments | Total Retail Tariff Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Electric Transmission | Operating Segments | Residential          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Electric Transmission | Operating Segments | Commercial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Electric Transmission | Operating Segments | Industrial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Electric Transmission | Operating Segments | Wholesale Transmission Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 446,200 394,300      
Electric Transmission | Operating Segments | Wholesale Market Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Electric Transmission | Operating Segments | Other Revenues from Contracts with Customers          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 3,800 3,400      
Electric Transmission | Operating Segments | (Reserve for)/Amortization of Revenues Subject to Refund          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0        
Water Distribution | Operating Segments          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 46,200 44,500      
Alternative Revenue Programs 2,200 1,800      
Other Revenues 100 100      
Operating Revenues 48,500 46,400      
Water Distribution | Operating Segments | Total Retail Tariff Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 43,900 42,500      
Water Distribution | Operating Segments | Residential          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 28,200 27,700      
Water Distribution | Operating Segments | Commercial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 14,600 13,800      
Water Distribution | Operating Segments | Industrial          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,100 1,000      
Water Distribution | Operating Segments | Wholesale Transmission Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 0 0      
Water Distribution | Operating Segments | Wholesale Market Sales Revenues          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 800 800      
Water Distribution | Operating Segments | Other Revenues from Contracts with Customers          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers 1,900 $ 1,200      
Water Distribution | Operating Segments | (Reserve for)/Amortization of Revenues Subject to Refund          
Disaggregation of Revenue [Line Items]          
Revenues from Contracts with Customers $ (400)        
v3.22.1
SEGMENT INFORMATION - Narrative (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
segment
CL&P  
Segment Reporting Information [Line Items]  
Number of reportable segments 1
NSTAR Electric  
Segment Reporting Information [Line Items]  
Number of reportable segments 1
PSNH  
Segment Reporting Information [Line Items]  
Number of reportable segments 1
Affiliated Entity  
Segment Reporting Information [Line Items]  
Amount of natural gas transmission purchased | $ $ 77.7
v3.22.1
SEGMENT INFORMATION - Summary of Segment Information and Segmented Total Assets (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Segment Reporting Information [Line Items]      
Operating Revenues $ 3,471,310 $ 2,825,840  
Depreciation and Amortization (526,300) (378,700)  
Other Operating Expenses (2,281,900) (1,861,500)  
Operating Income/(Loss) 663,055 585,568  
Interest Expense (153,245) (137,766)  
Other Income, Net 71,561 34,201  
Net Income/(Loss) Attributable to Common Shareholders 443,446 366,143  
Cash Flows Used for Investments in Plant 764,594 688,983  
Assets 49,289,152   $ 48,492,144
Other      
Segment Reporting Information [Line Items]      
Operating Revenues 383,500 343,000  
Depreciation and Amortization (30,200) (27,300)  
Other Operating Expenses (331,400) (299,500)  
Operating Income/(Loss) 21,900 16,200  
Interest Expense (46,800) (41,600)  
Other Income, Net 495,900 424,100  
Net Income/(Loss) Attributable to Common Shareholders 468,700 394,900  
Cash Flows Used for Investments in Plant 62,100 47,800  
Assets 23,394,300   22,674,700
Eliminations      
Segment Reporting Information [Line Items]      
Operating Revenues (709,800) (645,000)  
Depreciation and Amortization 1,600 1,000  
Other Operating Expenses 708,800 644,800  
Operating Income/(Loss) 600 800  
Interest Expense 10,100 11,600  
Other Income, Net (493,100) (421,000)  
Net Income/(Loss) Attributable to Common Shareholders (482,400) (408,600)  
Cash Flows Used for Investments in Plant 0 0  
Assets (22,647,900)   (21,738,600)
Electric Distribution | Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenues 2,386,300 1,900,300  
Depreciation and Amortization (351,600) (221,900)  
Other Operating Expenses (1,845,600) (1,530,500)  
Operating Income/(Loss) 189,100 147,900  
Interest Expense (59,400) (53,300)  
Other Income, Net 47,600 20,700  
Net Income/(Loss) Attributable to Common Shareholders 140,900 93,200  
Cash Flows Used for Investments in Plant 280,500 256,600  
Assets 25,883,200   25,411,200
Natural Gas Distribution | Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenues 927,600 780,500  
Depreciation and Amortization (51,900) (45,700)  
Other Operating Expenses (657,300) (535,800)  
Operating Income/(Loss) 218,400 199,000  
Interest Expense (15,800) (13,900)  
Other Income, Net 10,100 3,900  
Net Income/(Loss) Attributable to Common Shareholders 164,000 147,600  
Cash Flows Used for Investments in Plant 127,300 131,800  
Assets 7,329,700   7,215,900
Electric Transmission | Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenues 435,200 400,600  
Depreciation and Amortization (81,900) (73,500)  
Other Operating Expenses (129,300) (115,400)  
Operating Income/(Loss) 224,000 211,700  
Interest Expense (33,200) (32,700)  
Other Income, Net 8,900 5,500  
Net Income/(Loss) Attributable to Common Shareholders 148,500 135,400  
Cash Flows Used for Investments in Plant 266,900 225,200  
Assets 12,757,800   12,377,800
Water Distribution | Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenues 48,500 46,400  
Depreciation and Amortization (12,300) (11,300)  
Other Operating Expenses (27,100) (25,100)  
Operating Income/(Loss) 9,100 10,000  
Interest Expense (8,200) (7,900)  
Other Income, Net 2,200 1,000  
Net Income/(Loss) Attributable to Common Shareholders 3,700 3,600  
Cash Flows Used for Investments in Plant 27,800 $ 27,600  
Assets $ 2,572,100   $ 2,551,100