NORTHERN STATES POWER CO, 10-Q filed on 4/28/2022
Quarterly Report
v3.22.1
Cover Page - shares
 3 Months Ended
Mar. 31, 2022
Apr. 28, 2022
Cover [Abstract]    
Entity Registrant Name NORTHERN STATES POWER CO  
Entity Central Index Key 0001123852  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2022  
Document Fiscal Period Focus Q1  
Amendment Flag false  
Document Period End Date Mar. 31, 2022  
Document Type 10-Q  
Document Quarterly Report true  
Document Transition Report false  
Entity File Number 001-31387  
Entity Incorporation, State or Country Code MN  
Entity Tax Identification Number 41-1967505  
Entity Address, Address Line One 414 Nicollet Mall  
Entity Address, City or Town Minneapolis  
Entity Address, State or Province MN  
Entity Address, Postal Zip Code 55401  
City Area Code (612)  
Local Phone Number 330-5500  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   1,000,000
v3.22.1
CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating revenues    
Electric, non-affiliates $ 1,125 $ 1,024
Electric, affiliates 129 115
Natural gas 434 204
Other 10 9
Total operating revenues 1,698 1,352
Operating expenses    
Electric fuel and purchased power 529 433
Cost of natural gas sold and transported 336 125
Cost of sales — other 5 5
Operating and maintenance expenses 306 298
Conservation program expenses 49 34
Depreciation and amortization 252 221
Taxes (other than income taxes) 73 69
Total operating expenses 1,550 1,185
Operating income 148 167
Other income, net 0 2
Allowance for funds used during construction — equity 6 7
Interest charges and financing costs    
Interest charges — includes other financing costs of $2 and $2, respectively 69 63
Allowance for funds used during construction — debt (2) (3)
Total interest charges and financing costs 67 60
Income before income taxes 87 116
Income tax benefit (40) (12)
Net income $ 127 $ 128
v3.22.1
CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (Parenthetical) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Income Statement [Abstract]    
Other financing costs $ 2 $ 2
v3.22.1
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Comprehensive income:    
Net income $ 127 $ 128
Derivative instruments:    
Reclassification of losses to net income, net of tax of $— and $—, respectively 0 (1)
Total other comprehensive income 0 1
Total comprehensive income $ 127 $ 129
v3.22.1
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (Parenthetical) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Statement of Comprehensive Income [Abstract]    
Reclassification of losses on derivatives to net income, tax $ 0 $ 0
v3.22.1
CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating activities    
Net income $ 127 $ 128
Adjustments to reconcile net income to cash provided by operating activities:    
Depreciation and amortization 252 223
Nuclear fuel amortization 30 30
Deferred income taxes (76) (8)
Allowance for equity funds used during construction (6) (7)
Provision for bad debts 7 6
Gain (loss) on hedging and derivative transactions (6) (6)
Changes in operating assets and liabilities:    
Accounts receivable (67) (12)
Accrued unbilled revenues 64 43
Inventories 53 38
Accounts payable (25) (38)
Net regulatory assets and liabilities 168 (268)
Other current liabilities 65 26
Pension and other employee benefit obligations (6) (36)
Other, net (6) (2)
Net cash provided by operating activities 574 117
Investing activities    
Capital/construction expenditures (341) (474)
Purchase of investment securities (156) (199)
Proceeds from the sale of investment securities 147 194
Investments in utility money pool arrangement (538) 0
Repayments from utility money pool arrangement 443 0
Other, net (1) (2)
Net cash used in investing activities (446) (481)
Financing activities    
Repayments of short-term borrowings, net 0 (179)
Borrowings under utility money pool arrangement 0 434
Repayments under utility money pool arrangement 0 (434)
Proceeds from issuance of long-term debt 0 836
Capital contributions (to) from parent (7)  
Capital contributions (to) from parent   424
Dividends paid to parent (146) (106)
Net cash (used in) provided by financing activities (153) 975
Net change in cash, cash equivalents and restricted cash (25) 611
Cash, cash equivalents and restricted cash at beginning of period 73 46
Cash, cash equivalents and restricted cash at end of period 48 657
Supplemental disclosure of cash flow information:    
Cash paid for interest (net of amounts capitalized) (73) (72)
Cash (paid) received for income taxes, net (6) 1
Other Noncash Investing and Financing Items [Abstract]    
Accrued property, plant and equipment additions 97 222
Inventory transfers to property, plant and equipment 6 5
Allowance for equity funds used during construction $ 6 $ 7
v3.22.1
CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Current assets    
Cash, cash equivalents and restricted cash at beginning of period $ 48 $ 73
Accounts receivable, net 497 429
Accounts receivable from affiliates 29 29
Investments in money pool arrangements 186 91
Accrued unbilled revenues 256 319
Inventories 250 309
Regulatory assets 491 527
Derivative instruments 53 53
Prepayments and other 52 46
Total current assets 1,862 1,876
Property, plant and equipment, net 16,521 16,430
Other assets    
Nuclear decommissioning fund and other investments 3,167 3,308
Regulatory assets 764 718
Derivative instruments 60 33
Operating lease right-of-use assets 387 408
Other 35 36
Total other assets 4,413 4,503
Total assets 22,796 22,809
Current liabilities    
Current portion of long-term debt 300 300
Accounts payable 440 522
Accounts payable to affiliates 54 63
Regulatory liabilities 161 117
Taxes accrued 346 260
Accrued interest 70 78
Dividends payable to parent 117 96
Derivative instruments 57 35
Operating lease liabilities 95 90
Other 185 166
Total current liabilities 1,825 1,727
Deferred credits and other liabilities    
Deferred income taxes 1,837 1,949
Deferred investment tax credits 16 17
Regulatory liabilities 1,939 1,927
Asset retirement obligations 2,638 2,585
Derivative instruments 81 71
Pension and employee benefit obligations 105 112
Operating lease liabilities 326 353
Other 47 48
Total deferred credits and other liabilities 6,989 7,062
Capitalization    
Long-term debt 6,449 6,447
Common stock — 5,000,000 shares authorized of $0.01 par value; 1,000,000 shares outstanding at March 31, 2022 and Dec. 31, 2021, respectively $ 0 $ 0
Common Stock, Shares Authorized 5,000,000 5,000,000
Common Stock, Par or Stated Value Per Share $ 0.01 $ 0.01
Common Stock, Shares, Outstanding 1,000,000 1,000,000
Additional paid in capital $ 5,202 $ 5,202
Retained earnings 2,351 2,391
Accumulated other comprehensive loss (20) (20)
Total common stockholder's equity 7,533 7,573
Total liabilities and equity $ 22,796 $ 22,809
v3.22.1
CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($)
$ in Millions
Total
Common Stock
Additional Paid In Capital
Retained Earnings
Accumulated Other Comprehensive Loss
Balance (in shares) at Dec. 31, 2020   1,000,000      
Beginning balance at Dec. 31, 2020 $ 6,769 $ 0 $ 4,585 $ 2,206 $ (22)
Increase (Decrease) in Stockholders' Equity          
Net income 128     128  
Other comprehensive income 1       1
Dividends declared on common stock (108)     (108)  
Contribution of capital by parent 400   400    
Balance (in shares) at Mar. 31, 2021   1,000,000      
Ending balance at Mar. 31, 2021 $ 7,190 $ 0 4,985 2,226 (21)
Balance (in shares) at Dec. 31, 2021 1,000,000 1,000,000      
Beginning balance at Dec. 31, 2021 $ 7,573 $ 0 5,202 2,391 (20)
Increase (Decrease) in Stockholders' Equity          
Net income 127     127  
Other comprehensive income 0        
Dividends declared on common stock $ (167)     (167)  
Balance (in shares) at Mar. 31, 2022 1,000,000 1,000,000      
Ending balance at Mar. 31, 2022 $ 7,533 $ 0 $ 5,202 $ 2,351 $ (20)
v3.22.1
Management's Opinion
 3 Months Ended
Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Management's Opinion
In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments necessary to present fairly, in accordance with GAAP, the financial position of NSP-Minnesota and its subsidiaries as of March 31, 2022 and Dec. 31, 2021; the results of NSP-Minnesota’s operations, including the components of net income and comprehensive income, and changes in stockholder’s equity for the three months ended March 31, 2022 and 2021; and NSP-Minnesota’s cash flows for the three months ended March 31, 2022 and 2021.
All adjustments are of a normal, recurring nature, except as otherwise disclosed. Management has also evaluated the impact of events occurring after March 31, 2022 up to the date of issuance of these consolidated financial statements. These statements contain all necessary adjustments and disclosures resulting from that evaluation. The Dec. 31, 2021 balance sheet information has been derived from the audited 2021 consolidated financial statements included in the NSP-Minnesota Annual Report on Form 10-K for the year ended Dec. 31, 2021.
Notes to the consolidated financial statements have been prepared pursuant to the rules and regulations of the SEC for Quarterly Reports on Form 10-Q. Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP on an annual basis have been condensed or omitted pursuant to such rules and regulations. For further information, refer to the consolidated financial statements and notes thereto included in the NSP-Minnesota Annual Report on Form 10-K for the year ended Dec. 31, 2021, filed with the SEC on Feb. 23, 2022. Due to the seasonality of NSP-Minnesota’s electric and natural gas sales, interim results are not necessarily an appropriate base from which to project annual results.
v3.22.1
Summary of Significant Accounting Policies
 3 Months Ended
Mar. 31, 2022
Accounting Policies [Abstract]  
Summary of Significant Accounting Policies The significant accounting policies set forth in Note 1 to the consolidated financial statements in the NSP-Minnesota Annual Report on Form 10-K for the year ended Dec. 31, 2021 appropriately represent, in all material respects, the current status of accounting policies and are incorporated herein by reference.
v3.22.1
Accounting Pronouncements
 3 Months Ended
Mar. 31, 2022
Accounting Standards Update and Change in Accounting Principle [Abstract]  
Accounting Pronouncements As of March 31, 2022, there was no material impact from the recent adoption of new accounting pronouncements, nor expected material impact from recently issued accounting pronouncements yet to be adopted, on NSP-Minnesota’s financial statements.
v3.22.1
Selected Balance Sheet Data
 3 Months Ended
Mar. 31, 2022
Balance Sheet Related Disclosures [Abstract]  
Selected Balance Sheet Data
(Millions of Dollars)March 31, 2022Dec. 31, 2021
Accounts receivable, net
Accounts receivable$546 $474 
Less allowance for bad debts(49)(45)
Accounts receivable, net$497 $429 
(Millions of Dollars)March 31, 2022Dec. 31, 2021
Inventories
Materials and supplies$184 $181 
Fuel58 81 
Natural gas8 47 
Total inventories$250 $309 
(Millions of Dollars)March 31, 2022Dec. 31, 2021
Property, plant and equipment, net
Electric plant$19,676 $19,154 
Natural gas plant1,917 1,864 
Common and other property1,056 1,007 
 Plant to be retired (a)
700 719 
Construction work in progress658 984 
Total property, plant and equipment24,007 23,728 
Less accumulated depreciation(7,768)(7,606)
Nuclear fuel3,085 3,081 
Less accumulated amortization(2,803)(2,773)
Property, plant and equipment, net$16,521 $16,430 
(a)Includes regulator-approved retirements of Sherco Units 1, 2 and 3 and A.S. King.
v3.22.1
Borrowings and Other Financing Instruments
 3 Months Ended
Mar. 31, 2022
Debt Disclosure [Abstract]  
Borrowings and Other Financing Instruments
Short-Term Borrowings
NSP-Minnesota meets its short-term liquidity requirements primarily through the issuance of commercial paper and borrowings under its credit facility and the money pool.
Money Pool — Xcel Energy and its utility subsidiaries have established a money pool arrangement that allows for short-term investments in and borrowings between the utility subsidiaries. Xcel Energy may make investments in the utility subsidiaries at market-based interest rates; however, the money pool arrangement does not allow the utility subsidiaries to make investments in Xcel Energy.
Money pool borrowings for NSP-Minnesota:
(Amounts in Millions, Except Interest Rates)Three Months Ended March 31, 2022Year Ended Dec. 31, 2021
Borrowing limit$250 $250 
Amount outstanding at period end— — 
Average amount outstanding— 6 
Maximum amount outstanding— 236 
Weighted average interest rate, computed on a daily basisN/A0.07 %
Weighted average interest rate at period endN/AN/A
Commercial Paper — Commercial paper outstanding for NSP-Minnesota:
(Amounts in Millions, Except Interest Rates)Three Months Ended March 31, 2022Year Ended Dec. 31, 2021
Borrowing limit$500 $500 
Amount outstanding at period end— — 
Average amount outstanding4 26 
Maximum amount outstanding50 317 
Weighted average interest rate, computed on a daily basis0.15 %0.18 %
Weighted average interest rate at period endN/AN/A
Letters of Credit — NSP-Minnesota uses letters of credit, generally with terms of one year, to provide financial guarantees for certain obligations. There were $11 million and $9 million of letters of credit outstanding under the credit facility at March 31, 2022 and Dec. 31, 2021, respectively. Amounts approximate their fair value and are subject to fees.
Revolving Credit Facility — In order to issue its commercial paper, NSP-Minnesota must have a revolving credit facility in place at least equal to the amount of its commercial paper borrowing limit and cannot issue commercial paper exceeding available capacity under this credit facility. The credit facility provides short-term financing in the form of notes payable to banks, letters of credit and back-up support for commercial paper borrowings.
NSP-Minnesota has the right to request an extension of the revolving credit facility termination date for two additional one-year periods. All extension requests are subject to majority bank group approval.
At March 31, 2022, NSP-Minnesota had the following committed revolving credit facility available (in millions of dollars):
Credit Facility (a)
Drawn (b)
Available
$500 $11 $489 
(a)Expires in June 2024.
(b)Includes outstanding commercial paper and letters of credit.
All credit facility bank borrowings, outstanding letters of credit and outstanding commercial paper reduce the available capacity under the credit facility. NSP-Minnesota had no direct advances on the credit facility outstanding at March 31, 2022 and Dec. 31, 2021.
Bilateral Credit Agreement — In April 2022, NSP-Minnesota’s uncommitted bilateral credit agreement was renewed for an additional one-year term. The credit agreement is limited in use to support letters of credit.
As of March 31, 2022, NSP-Minnesota’s outstanding letters of credit under the bilateral credit agreement were as follows:
(Millions of Dollars)LimitAmount OutstandingAvailable
NSP-Minnesota$75 $45 $30 
v3.22.1
Revenues
 3 Months Ended
Mar. 31, 2022
Revenue from Contract with Customer [Abstract]  
Revenues
Revenue is classified by the type of goods/services rendered and market/customer type. NSP-Minnesota’s operating revenues consisted of the following:
Three Months Ended March 31, 2022
(Millions of Dollars)ElectricNatural GasAll OtherTotal
Major revenue types
Revenue from contracts with customers:
Residential$337 $235 $6 $578 
C&I514 180 — 694 
Other9 — 4 13 
Total retail860 415 10 1,285 
Wholesale124 — — 124 
Transmission61 — — 61 
Interchange129 — — 129 
Other6 2 — 8 
Total revenue from contracts with customers1,180 417 10 1,607 
Alternative revenue and other74 17 — 91 
Total revenues$1,254 $434 $10 $1,698 
Three Months Ended March 31, 2021
(Millions of Dollars)ElectricNatural GasAll OtherTotal
Major revenue types
Revenue from contracts with customers:
Residential$326 $114 $7 $447 
C&I416 79 — 495 
Other8 — 2 10 
Total retail750 193 9 952 
Wholesale98 — — 98 
Transmission57 — — 57 
Interchange115 — — 115 
Other2 — — 2 
Total revenue from contracts with customers1,022 193 9 1,224 
Alternative revenue and other117 11 — 128 
Total revenues$1,139 $204 $9 $1,352 
v3.22.1
Income Taxes
 3 Months Ended
Mar. 31, 2022
Income Tax Disclosure [Abstract]  
Income Taxes
6. Income Taxes
Note 7 to the consolidated financial statements included in NSP-Minnesota’s Annual Report on Form 10-K for the year ended Dec. 31, 2021 represents, in all material respects, the current status of other income tax matters except to the extent noted below, and are incorporated herein by reference.
Difference between the statutory rate and ETR:
Three Months Ended March 31
20222021
Federal statutory rate21.0 %21.0 %
State tax (net of federal tax effect)7.0 7.0 
Increases (decreases) in tax from:
Wind PTCs(68.6)(30.4)
Plant regulatory differences (a)
(5.7)(7.8)
Other tax credits, net operating loss & tax credit allowances(1.4)(1.3)
Other (net)1.7 1.2 
Effective income tax rate(46.0)%(10.3)%
(a)Regulatory differences for income tax primarily relate to the credit of excess deferred taxes to customers through the average rate assumption method. Income tax benefits associated with the credit of excess deferred credits are offset by corresponding revenue reductions.
v3.22.1
Fair Value of Financial Assets and Liabilities
 3 Months Ended
Mar. 31, 2022
Fair Value Disclosures [Abstract]  
Fair Value of Financial Assets and Liabilities
Fair Value Measurements
Accounting guidance for fair value measurements and disclosures provides a single definition of fair value and requires disclosures about assets and liabilities measured at fair value. A hierarchical framework for disclosing the observability of the inputs utilized in measuring assets and liabilities at fair value is established by this guidance.
•Level 1 — Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. The types of assets and liabilities included in Level 1 are highly liquid and actively traded instruments with quoted prices.
•Level 2 — Pricing inputs are other than quoted prices in active markets, but are either directly or indirectly observable as of the reporting date. The types of assets and liabilities included in Level 2 are typically either comparable to actively traded securities or contracts, or priced with models using highly observable inputs.
•Level 3 — Significant inputs to pricing have little or no observability as of the reporting date. The types of assets and liabilities included in Level 3 are those valued with models requiring significant management judgment or estimation.
Specific valuation methods include:
Cash equivalents — The fair values of cash equivalents are generally based on cost plus accrued interest; money market funds are measured using quoted NAV.
Investments in equity securities and other funds — Equity securities are valued using quoted prices in active markets. The fair values for commingled funds are measured using NAVs. The investments in commingled funds may be redeemed for NAV with proper notice. Private equity commingled fund investments require approval of the fund for any unscheduled redemption, and such redemptions may be approved or denied by the fund at its sole discretion.
Unscheduled distributions from real estate commingled funds’ investments may be redeemed with proper notice, however, withdrawals may be delayed or discounted as a result of fund illiquidity.
Investments in debt securities — Fair values for debt securities are determined by a third-party pricing service using recent trades and observable spreads from benchmark interest rates for similar securities.
Interest rate derivatives — The fair values of interest rate derivatives are based on broker quotes that utilize current market interest rate forecasts.
Commodity derivatives — The methods used to measure the fair value of commodity derivative forwards and options utilize forward prices and volatilities, as well as pricing adjustments for specific delivery locations and are generally assigned a Level 2 classification. When contractual settlements relate to inactive delivery locations or extend to periods beyond those readily observable on active exchanges or quoted by brokers, the significance of the use of less observable inputs on a valuation is evaluated, and may result in Level 3 classification.
Electric commodity derivatives held by NSP-Minnesota include transmission congestion instruments, generally referred to as FTRs. FTRs purchased from a RTO are financial instruments that entitle or obligate the holder to monthly revenues or charges based on transmission congestion across a given transmission path. The value of an FTR is derived from, and designed to offset, the cost of transmission congestion. In addition to overall transmission load, congestion is also influenced by the operating schedules of power plants and the consumption of electricity pertinent to a given transmission path. Unplanned plant outages, scheduled plant maintenance, changes in the relative costs of fuels used in generation, weather and overall changes in demand for electricity can each impact the operating schedules of the power plants on the transmission grid and the value of an FTR.
If forecasted costs of electric transmission congestion increase or decrease for a given FTR path, the value of that particular FTR instrument will likewise increase or decrease. Given the limited observability of certain inputs to the value of FTRs between auction processes, including expected plant operating schedules and retail and wholesale demand, fair value measurements for FTRs have been assigned a Level 3.
Non-trading monthly FTR settlements are expected to be recovered through fuel and purchased energy cost recovery mechanisms, and therefore changes in the fair value of the yet to be settled portions of most FTRs are deferred as a regulatory asset or liability. Given this regulatory treatment and the limited magnitude of NSP-Minnesota’s FTRs relative to its electric utility operations, the numerous unobservable quantitative inputs pertinent to the value of FTRs are immaterial to the consolidated financial statements of NSP-Minnesota.
Non-Derivative Fair Value Measurements
The Nuclear Regulatory Commission requires NSP-Minnesota to maintain a portfolio of investments to fund the costs of decommissioning its nuclear generating plants. Assets of the nuclear decommissioning fund are legally restricted for the purpose of decommissioning these facilities. The fund contains cash equivalents, debt securities, equity securities and other investments. NSP-Minnesota uses the MPUC approved asset allocation for the investment targets by asset class for the qualified trust.
NSP-Minnesota recognizes the costs of funding the decommissioning over the lives of the nuclear plants, assuming rate recovery of all costs. Realized and unrealized gains on fund investments over the life of the fund are deferred as an offset of NSP-Minnesota’s regulatory asset for nuclear decommissioning costs. Consequently, any realized and unrealized gains and losses on securities in the nuclear decommissioning fund are deferred as a component of the regulatory asset.
Unrealized gains for the nuclear decommissioning fund were $1.2 billion and $1.3 billion as of March 31, 2022 and Dec. 31, 2021, respectively, and unrealized losses were $37 million and $7 million as of March 31, 2022 and Dec. 31, 2021, respectively.
Non-derivative instruments with recurring fair value measurements in the nuclear decommissioning fund:
March 31, 2022
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3NAVTotal
Nuclear decommissioning fund (a)
Cash equivalents$80 $80 $— $— $— $80 
Commingled funds871 — — — 1,258 1,258 
Debt securities626 — 606 10 — 616 
Equity securities409 1,159 1 — — 1,160 
Total$1,986 $1,239 $607 $10 $1,258 $3,114 
(a)Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $53 million of rabbi trust assets and other miscellaneous investments.
Dec. 31, 2021
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3NAVTotal
Nuclear decommissioning fund (a)
Cash equivalents$64 $64 $— $— $— $64 
Commingled funds856 — — — 1,294 1,294 
Debt securities631 — 666 9 — 675 
Equity securities411 1,222 1 — — 1,223 
Total$1,962 $1,286 $667 $9 $1,294 $3,256 
(a)Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $52 million of rabbi trust assets and miscellaneous investments.
For the three months ended March 31, 2022 and 2021, there were immaterial Level 3 nuclear decommissioning fund investments or transfer of amounts between levels.
Contractual maturity dates of debt securities in the nuclear decommissioning fund as of March 31, 2022:
Final Contractual Maturity
(Millions of Dollars)Due in 1 year or LessDue in 1 to 5 YearsDue in 5 to 10 YearsDue after 10 YearsTotal
Debt securities$2 $142 $193 $279 $616 
Rabbi Trusts
NSP-Minnesota has established a rabbi trust to provide partial funding for future deferred compensation plan distributions.
Cost and fair value of assets held in rabbi trusts:
March 31, 2022
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3Total
Rabbi Trusts (a)
Mutual funds$10 $12 $— $— $12 
Total$10 $12 $— $— $12 
Dec. 31, 2021
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3Total
Rabbi Trusts (a)
Mutual funds$10 $13 $— $— $13 
Total$10 $13 $— $— $13 
(a)    Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets.
Derivative Instruments Fair Value Measurements
NSP-Minnesota enters into derivative instruments, including forward contracts, futures, swaps and options, for trading purposes and to manage risk in connection with changes in interest rates, utility commodity prices and vehicle fuel prices.
Interest Rate Derivatives — NSP-Minnesota enters into various instruments that effectively fix the yield or price on a specified benchmark interest rate for an anticipated debt issuance for a specific period. These derivative instruments are generally designated as cash flow hedges for accounting purposes, with changes in fair value prior to settlement recorded as other comprehensive income.
At March 31, 2022, accumulated other comprehensive loss related to interest rate derivatives included $1 million of net losses expected to be reclassified into earnings during the next 12 months as the hedged interest rate transactions impact earnings. As of March 31, 2022, NSP-Minnesota had no unsettled interest rate derivatives.
Wholesale and Commodity Trading Risk — NSP-Minnesota conducts various wholesale and commodity trading activities, including the purchase and sale of electric capacity, energy, energy-related instruments and natural gas-related instruments, including derivatives. NSP-Minnesota is allowed to conduct these activities within guidelines and limitations as approved by its risk management committee, comprised of management personnel not directly involved in the activities governed by this policy. Sharing of any margins is determined through state regulatory proceedings as well as the operation of the FERC approved joint operating agreement.
Commodity Derivatives — NSP-Minnesota enters into derivative instruments to manage variability of future cash flows from changes in commodity prices in its electric and natural gas operations, as well as for trading purposes. This could include the purchase or sale of energy or energy-related products, natural gas to generate electric energy, natural gas for resale, FTRs, vehicle fuel, and weather derivatives.
At March 31, 2022, NSP-Minnesota had no commodity contracts designated as cash flow hedges. NSP-Minnesota may enter into derivative instruments that mitigate commodity price risk on behalf of electric and natural gas customers, but may not be designated as qualifying hedging transactions. The classification of gains or losses for these instruments as a regulatory asset or liability, if applicable, is based on approved regulatory recovery mechanisms.
NSP-Minnesota also enters into commodity derivative instruments for trading purposes not directly related to commodity price risks associated with serving its electric and natural gas customers. Changes in the fair value of these commodity derivatives are recorded in electric operating revenues, net of amounts credited to customers under margin-sharing mechanisms.
Gross notional amounts of commodity forwards, options and FTRs:
(Amounts in Millions) (a)(b)
March 31, 2022Dec. 31, 2021
Megawatt hours of electricity40 57 
Million British thermal units of natural gas86 85 
(a)Amounts are not reflective of net positions in the underlying commodities.
(b)Notional amounts for options are included on a gross basis, but are weighted for the probability of exercise.
Consideration of Credit Risk and Concentrations — NSP-Minnesota continuously monitors the creditworthiness of counterparties to its interest rate derivatives and commodity derivative contracts, prior to settlement, and assesses each counterparty’s ability to perform on the transactions set forth in the contracts. Impact of credit risk was immaterial to the fair value of unsettled commodity derivatives presented on the consolidated balance sheets.
NSP-Minnesota’s most significant concentrations of credit risk with particular entities or industries are contracts with counterparties to its wholesale, trading and non-trading commodity activities.
As of March 31, 2022, seven of NSP-Minnesota’s ten most significant counterparties for these activities, comprising $46 million, or 48%, of this credit exposure, had investment grade credit ratings from S&P Global Ratings, Moody’s Investor Services or Fitch Ratings. One of the ten most significant counterparties, comprising $21 million, or 22%, of this credit exposure, were not rated by these external ratings agencies, but based on NSP-Minnesota’s internal analysis, had credit quality consistent with investment grade. Two of these significant counterparties, comprising $27 million or 28% of this credit exposure, had credit quality less than investment grade, based on internal analysis. Four of these significant counterparties are municipal or cooperative electric entities, RTOs or other utilities.
Impact of Derivative Activity —
Pre-Tax Fair Value Gains (Losses) Recognized During the Period in:
(Millions of Dollars)Accumulated Other Comprehensive LossRegulatory (Assets) and Liabilities
Three Months Ended March 31, 2022
Other derivative instruments
Natural gas commodity$— $2 
Total$— $2 
Three Months Ended March 31, 2021
Other derivative instruments
Natural gas commodity$— $1 
Total$— $1 

Pre-Tax (Gains) Losses Reclassified into Income During the Period from:Pre-Tax Gains (Losses) Recognized During the Period in Income
(Millions of Dollars)Accumulated Other Comprehensive LossRegulatory Assets and (Liabilities)
Three Months Ended March 31, 2022
Other derivative instruments
Commodity trading$— $— $1 
(a)
Electric commodity— (1)
(b)
— 
Natural gas commodity— 1 
(c)
(5)
(c)(d)
Total$— $— $(4)
Pre-Tax (Gains) Losses Reclassified
into Income During the Period from:		Pre-Tax Gains (Losses)
Recognized
During the Period in Income
(Millions of Dollars)Accumulated Other Comprehensive LossRegulatory
Assets and (Liabilities)
Three Months Ended March 31, 2021
Other derivative instruments
Commodity trading$— $— $31 
(a)
Electric commodity— (1)
(b)
— 
Natural gas commodity— 1 
(c)
(3)
(c)(d)
Total$— $— $28 
(a)Recorded to electric operating revenues. Portions of these gains and losses are subject to sharing with electric customers through margin-sharing mechanisms and deducted from gross revenue, as appropriate.
(b)Recorded to electric fuel and purchased power. These derivative settlement gains and losses are shared with electric customers through fuel and purchased energy cost-recovery mechanisms, and reclassified out of income as regulatory assets or liabilities, as appropriate.
(c)Settlement losses related to natural gas operations are recorded to cost of natural gas sold and transported. These losses are subject to cost-recovery mechanisms and reclassified out of income to a regulatory asset, as appropriate.
(d)Relates primarily to option premium amortization.
NSP-Minnesota had no derivative instruments designated as fair value hedges during the three months ended March 31, 2022 and 2021.
Credit Related Contingent Features — Contract provisions for derivative instruments that NSP-Minnesota enters into, including those accounted for as normal purchase-normal sale contracts and therefore not reflected on the consolidated balance sheets, may require the posting of collateral or settlement of the contracts for various reasons, including if NSP-Minnesota’s credit ratings are downgraded below its investment grade credit rating by any of the major credit rating agencies. As of March 31, 2022 and Dec. 31, 2021, there were $4 million and $3 million, respectively, of derivative liabilities with such underlying contract provisions. Certain contracts also contain cross default provisions that may require the posting of collateral or settlement of the contracts if there was a failure under the other financing arrangements related to payment terms or other covenants. As of March 31, 2022 and Dec. 31, 2021, there were approximately $83 million and $48 million, respectively, of derivative liabilities with such underlying contract provisions.
Certain derivative instruments are also subject to contract provisions that contain adequate assurance clauses. These provisions allow counterparties to seek performance assurance, including cash collateral, in the event that NSP-Minnesota’s ability to fulfill its contractual obligations is reasonably expected to be impaired. NSP-Minnesota had no collateral posted related to adequate assurance clauses in derivative contracts as of March 31, 2022 and Dec. 31, 2021.
Recurring Fair Value Measurements — NSP-Minnesota’s derivative assets and liabilities measured at fair value on a recurring basis were as follows:
March 31, 2022Dec. 31, 2021
Fair ValueFair Value Total
Netting (a)
TotalFair ValueFair Value Total
Netting (a)
Total
(Millions of Dollars)Level 1Level 2Level 3Level 1Level 2Level 3
Current derivative assets
Other derivative instruments:
Commodity trading$26 $76 $53 $155 $(114)$41 $9 $40 $22 $71 $(53)$18 
Electric commodity— — 10 10 — 10 — — 30 30 (1)29 
Natural gas commodity— — — — — — — 6 — 6 — 6 
Total current derivative assets$26 $76 $63 $165 $(114)51 $9 $46 $52 $107 $(54)53 
PPAs (b)
2 — 
Current derivative instruments$53 $53 
Noncurrent derivative assets
Other derivative instruments:
Commodity trading$17 $42 $63 $122 $(62)$60 $6 $34 $35 $75 $(42)$33 
Total noncurrent derivative assets$17 $42 $63 $122 $(62)$60 $6 $34 $35 $75 $(42)$33 
March 31, 2022Dec. 31, 2021
Fair ValueFair Value Total
Netting (a)
TotalFair ValueFair Value Total
Netting (a)
Total
(Millions of Dollars)Level 1Level 2Level 3Level 1Level 2Level 3
Current derivative liabilities
Other derivative instruments:
Commodity trading$32 $113 $12 $157 $(114)$43 $13 $58 $4 $75 $(58)$17 
Electric commodity— — 1 1 (1)— — — 1 1 (1)— 
Natural gas commodity— — — — — — — 4 — 4 — 4 
Total current derivative liabilities$32 $113 $13 $158 $(115)43 $13 $62 $5 $80 $(59)21 
PPAs (b)
14 14 
Current derivative instruments$57 $35 
Noncurrent derivative liabilities
Other derivative instruments:
Commodity trading$34 $63 $37 $134 $(86)$48 $15 $48 $26 $89 $(53)$36 
Total noncurrent derivative liabilities$34 $63 $37 $134 $(86)48 $15 $48 $26 $89 $(53)36 
PPAs (b)
33 35 
Noncurrent derivative instruments$81 $71 
(a)NSP-Minnesota nets derivative instruments and related collateral on its consolidated balance sheets when supported by a legally enforceable master netting agreement, and all derivative instruments and related collateral amounts were subject to master netting agreements at March 31, 2022 and Dec. 31, 2021. At both March 31, 2022 and Dec. 31, 2021, derivative assets and liabilities include $15 million of obligations to return cash collateral. At March 31, 2022 and Dec. 31, 2021 derivative assets and liabilities include rights to reclaim cash collateral of $24 million and $16 million, respectively. The counterparty netting excludes settlement receivables and payables and non-derivative amounts that may be subject to the same master netting agreements.
(b)During 2006, Xcel Energy qualified these contracts under the normal purchase exception. Based on this qualification, the contracts are no longer adjusted to fair value and the previous carrying value of these contracts will be amortized over the remaining contract lives along with the offsetting regulatory assets and liabilities.
Changes in Level 3 commodity derivatives for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31
(Millions of Dollars)20222021
Balance at Jan 1$56 $(11)
Settlements(19)(7)
Net transactions recorded during the period:
Gains recognized in earnings (a)
49 30 
Net losses recognized as regulatory assets and liabilities(10)— 
Balance at March 31$76 $12 
(a)Level 3 net gains recognized in earnings are subject to offsetting net losses of derivative instruments categorized as levels 1 and 2 in the income statement.
NSP-Minnesota recognizes transfers between levels as of the beginning of each period. There were no transfers of amounts between levels for derivative instruments for the three months ended March 31, 2022 and 2021.
Fair Value of Long-Term Debt
Other financial instruments for which the carrying amount did not equal fair value:
March 31, 2022Dec. 31, 2021
(Millions of Dollars)Carrying AmountFair ValueCarrying AmountFair Value
Long-term debt, including current portion$6,749 $6,984 $6,747 $7,761 
Fair value of NSP-Minnesota’s long-term debt is estimated based on recent trades and observable spreads from benchmark interest rates for similar securities. Fair value estimates are based on information available to management as of March 31, 2022 and Dec. 31, 2021 and given the observability of the inputs, fair values presented for long-term debt were assigned as Level 2.
v3.22.1
Benefit Plans and Other Postretirement Benefits
 3 Months Ended
Mar. 31, 2022
Retirement Benefits [Abstract]  
Benefit Plans and Other Postretirement Benefits
Components of Net Periodic Benefit Cost
Three Months Ended March 31
2022202120222021
(Millions of Dollars)Pension BenefitsPostretirement Health
Care Benefits
Service cost$7 $7 $— $— 
Interest cost (a)
6 6 1 1 
Expected return on plan assets (a)
(12)(13)— — 
Amortization of prior service credit (a)
— — (1)(1)
Amortization of net loss (a)
6 9 — — 
Settlement charge (b)
(1)— — — 
Net periodic benefit cost6 9 — — 
Effects of regulation1 (1)— — 
Net benefit cost recognized for financial reporting$7 $8 $— $— 
(a)     The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.
(b)     In the first quarter of 2022, NSP-Minnesota recognized $1 million in settlement charge true-ups related to fourth quarter 2021.
In January 2022, contributions of $50 million were made across four of Xcel Energy’s pension plans, of which $5 million was attributable to NSP-Minnesota. Xcel Energy does not expect additional pension contributions during 2022.
v3.22.1
Commitments and Contingencies
 3 Months Ended
Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies
Legal
NSP-Minnesota is involved in various litigation matters in the ordinary course of business. The assessment of whether a loss is probable or is a reasonable possibility, and whether the loss or a range of loss is estimable, often involves a series of complex judgments about future events. Management maintains accruals for losses probable of being incurred and subject to reasonable estimation. Management is sometimes unable to estimate an amount or range of a reasonably possible loss in certain situations, including but not limited to when (1) the damages sought are indeterminate, (2) the proceedings are in the early stages, or (3) the matters involve novel or unsettled legal theories.
In such cases, there is considerable uncertainty regarding the timing or ultimate resolution, including a possible eventual loss. For current proceedings not specifically reported herein, management does not anticipate that the ultimate liabilities, if any, would have a material effect on NSP-Minnesota’s consolidated financial statements. Legal fees are generally expensed as incurred.
Rate Matters and Other
NSP-Minnesota is involved in various regulatory proceedings arising in the ordinary course of business. Until resolution, typically in the form of a rate order, uncertainties may exist regarding the ultimate rate treatment for certain activities and transactions. Amounts have been recognized for probable and reasonably estimable losses that may result. Unless otherwise disclosed, any reasonably possible range of loss in excess of any recognized amount is not expected to have a material effect on the financial statements.
Minnesota Winter Storm Uri Costs — In Minnesota, NSP-Minnesota is participating in a contested case regarding the prudency of incremental natural gas costs incurred during Winter Storm Uri. Other parties to the case have recommended significant cost disallowances, and while ultimate resolution of the matter is uncertain, it is reasonably possible that the MPUC could disallow certain deferred costs, resulting in earnings losses.
NSP-Minnesota strongly disagrees with the recommendations of the DOC, OAG and CUB, and believes that it acted prudently and according to MPUC approved procedures for the best interest of its customers and stakeholders.
NSP-Minnesota filed rebuttal testimony in January 2022 detailing its position that the disallowances recommended by other parties lack any merit in the prudency review given the pertinent facts regarding NSP-Minnesota’s actions before, during and after the storm event. In March 2022, following February 2022 ALJ hearings, the Company and intervenors subsequently submitted initial and reply briefs to the ALJ. The OAG modified its position, recommending disallowances of up to $148 million, the largest recommendation among the intervenor positions. An ALJ decision is expected in late May and an MPUC decision is expected in Q3 of 2022.
Sherco — In 2018, NSP-Minnesota and SMMPA (Co-owner of Sherco Unit 3) reached a settlement with GE related to a 2011 incident, which damaged the turbine at Sherco Unit 3 and resulted in an extended outage for repair. NSP-Minnesota notified the MPUC of its proposal to refund settlement proceeds to customers through the fuel clause adjustment.
In March 2019, the MPUC approved NSP-Minnesota’s settlement refund proposal. Additionally, the MPUC decided to withhold any decision as to NSP-Minnesota’s prudence in connection with the incident at Sherco Unit 3 until after conclusion of an appeal pending between GE and NSP-Minnesota’s insurers. In February 2020, the Minnesota Court of Appeals affirmed the district court’s judgment in favor of GE. In March 2020, NSP-Minnesota’s insurers filed a petition seeking additional review by the Minnesota Supreme Court.
In April 2020, the Minnesota Supreme Court denied the insurers’ petition for further review, ending the litigation.
In January 2021, the OAG and DOC recommended that NSP-Minnesota refund approximately $17 million of replacement power costs previously recovered through the fuel clause adjustment. NSP-Minnesota subsequently filed its response, asserting that it acted prudently in connection with the Sherco Unit 3 outage, the MPUC has previously disallowed $22 million of related costs and no additional refund or disallowance is appropriate. A final decision by the MPUC is pending. A loss related to this matter is deemed remote.
Westmoreland Arbitration — In November 2014, insurers of the Westmoreland Coal Company filed an arbitration demand against NSP-Minnesota, SMMPA and Western Fuels Association, seeking recovery of alleged $36 million of business losses due to a turbine failure at Sherco Unit 3. Westmoreland’s insurers have recently clarified that they will seek to recover $19 million in damages, plus prejudgment interest. The Westmoreland insurers claim NSP-Minnesota’s invocation of the force majeure clause to stop the supply of coal was improper because the incident was allegedly caused by NSP-Minnesota’s failure to conform to industry maintenance standards.
NSP-Minnesota denies the claims asserted by the Westmoreland insurers and believes it properly stopped the supply of coal based upon the force majeure provision. Parties participated in mediation in the second quarter of 2022. A final hearing has been scheduled for October 2022. At this stage of the proceeding, a reasonable estimate of damages or range of damages cannot be determined.
MISO ROE Complaints —
Environmental
MGP, Landfill and Disposal Sites
NSP-Minnesota is investigating, remediating or performing post-closure actions at seven MGP, landfill or other disposal sites across its service territories.
NSP-Minnesota has recognized its best estimate of costs/liabilities from final resolution of these issues, however, the outcome and timing are unknown. In addition, there may be insurance recovery and/or recovery from other potentially responsible parties, offsetting a portion of costs incurred.
Environmental Requirements — Water and Waste
Coal Ash Regulation — NSP-Minnesota’s operations are subject to federal and state regulations that impose requirements for handling, storage, treatment and disposal of solid waste. Under the CCR Rule, utilities are required to complete groundwater sampling around their CCR landfills and surface impoundments. Currently, NSP-Minnesota has three regulated ash units in operation.
NSP-Minnesota is conducting groundwater sampling and monitoring and implementing assessment of corrective measures at certain CCR landfills and surface impoundments. No results above the groundwater protection standards in the rule were identified.
In August 2020, the EPA published its final rule to implement closure by April 2021 for all CCR impoundments affected by the August 2018 D.C. Circuit ruling. This final rule required Xcel Energy to expedite closure plans for one impoundment.
In October 2020, NSP-Minnesota completed construction and placed in service a new impoundment to replace the clay lined impoundment. With the new ash pond in service, NSP-Minnesota has initiated closure activities for the existing ash pond at an estimated cost of $4 million. NSP-Minnesota has five years to complete closure activities.
Closure costs for existing impoundments are included in the calculation of the asset retirement obligation.
Leases
NSP-Minnesota evaluates contracts that may contain leases, including PPAs and arrangements for the use of office space and other facilities, vehicles and equipment. A contract contains a lease if it conveys the exclusive right to control the use of a specific asset.
Components of lease expense:
Three Months Ended March 31
(Millions of Dollars)20222021
Operating leases
PPA capacity payments$24 $19 
Other operating leases (a)
32
Total operating lease expense (b)
$27 $21 
(a)Includes immaterial short-term lease expense for 2022 and 2021.
(b)PPA capacity payments are included in electric fuel and purchased power on the consolidated statements of income. Expense for other operating leases is included in O&M expense and electric fuel and purchased power.
Commitments under operating leases as of March 31, 2022:
(Millions of Dollars)PPA Operating
Leases
Other Operating
Leases
Total
Operating
Leases
Total minimum obligation$390 $71 $461 
Interest component of obligation(28)(12)(40)
Present value of minimum obligation$362 $59 421 
Less current portion(95)
Noncurrent operating lease liabilities$326 
v3.22.1
Other Comprehensive Income (Loss)
 3 Months Ended
Mar. 31, 2022
Stockholders' Equity Note [Abstract]  
Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss), net of tax, for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31, 2022Three Months Ended March 31, 2021
(Millions of Dollars)Gains and Losses on Cash Flow HedgesDefined Benefit Pension and Postretirement ItemsTotalGains and Losses on Cash Flow HedgesDefined Benefit Pension and Postretirement ItemsTotal
Accumulated other comprehensive loss at Jan. 1$(17)$(3)$(20)$(19)$(3)$(22)
Losses reclassified from net accumulated other comprehensive loss:
Interest rate derivatives, net of taxes of $— and $—, respectively (a)
— — — 1 — 1 
Accumulated other comprehensive loss at March 31$(17)$(3)$(20)$(18)$(3)$(21)
(a)Included in interest charges.
v3.22.1
Segment Information
 3 Months Ended
Mar. 31, 2022
Segment Reporting [Abstract]  
Segment Information
NSP-Minnesota evaluates performance based on profit or loss generated from the product or service provided. These segments are managed separately because the revenue streams are dependent upon regulated rate recovery, which is separately determined for each segment.
NSP-Minnesota has the following reportable segments:
•Regulated Electric — The regulated electric utility segment generates electricity which is transmitted and distributed in Minnesota, North Dakota and South Dakota. In addition, this segment includes sales for resale and provides wholesale transmission service to various entities in the United States. The regulated electric utility segment also includes NSP-Minnesota’s wholesale commodity and trading operations.
•Regulated Natural Gas — The regulated natural gas utility segment transports, stores and distributes natural gas in portions of Minnesota and North Dakota.
NSP-Minnesota also presents All Other, which includes operating segments with revenues below the necessary quantitative thresholds. Those operating segments primarily include appliance repair services, non-utility real estate activities and revenues associated with processing solid waste into refuse-derived fuel.
Asset and capital expenditure information is not provided for NSP-Minnesota’s reportable segments. As an integrated electric and natural gas utility, NSP-Minnesota operates significant assets that are not dedicated to a specific business segment. Reporting assets and capital expenditures by business segment would require arbitrary and potentially misleading allocations, which may not necessarily reflect the assets that would be required for the operation of the business segments on a stand-alone basis.
Certain costs, such as common depreciation, common O&M expenses and interest expense are allocated based on cost causation allocators across each segment. In addition, a general allocator is used for certain general and administrative expenses, including office supplies, rent, property insurance and general advertising.
NSP-Minnesota’s segment information:
Three Months Ended March 31
(Millions of Dollars)20222021
Regulated Electric
Total revenues (a)
$1,254 $1,139 
Net income98 107 
Regulated Natural Gas
   Total revenues(b)
$434 $204 
Net income29 20 
All Other
Total revenues$10 $9 
Net income— 1 
Consolidated Total
Total revenues (a)(b)
$1,698 $1,352 
Net income127 128 
(a)    Operating revenues include $129 million and $115 million of affiliate electric revenue for the three months ended March 31, 2022 and 2021.
(b)    Operating revenues include an immaterial amount of affiliate gas revenue for the three months ended March 31, 2022 and 2021.
v3.22.1
Selected Balance Sheet Data (Tables)
 3 Months Ended
Mar. 31, 2022
Balance Sheet Related Disclosures [Abstract]  
Accounts Receivable, Net
(Millions of Dollars)March 31, 2022Dec. 31, 2021
Accounts receivable, net
Accounts receivable$546 $474 
Less allowance for bad debts(49)(45)
Accounts receivable, net$497 $429 
Inventories
(Millions of Dollars)March 31, 2022Dec. 31, 2021
Inventories
Materials and supplies$184 $181 
Fuel58 81 
Natural gas8 47 
Total inventories$250 $309 
Property, plant and equipment, net
(Millions of Dollars)March 31, 2022Dec. 31, 2021
Property, plant and equipment, net
Electric plant$19,676 $19,154 
Natural gas plant1,917 1,864 
Common and other property1,056 1,007 
 Plant to be retired (a)
700 719 
Construction work in progress658 984 
Total property, plant and equipment24,007 23,728 
Less accumulated depreciation(7,768)(7,606)
Nuclear fuel3,085 3,081 
Less accumulated amortization(2,803)(2,773)
Property, plant and equipment, net$16,521 $16,430 
(a)Includes regulator-approved retirements of Sherco Units 1, 2 and 3 and A.S. King.
v3.22.1
Borrowings and Other Financing Instruments (Tables)
 3 Months Ended
Mar. 31, 2022
Borrowings and Other Financing Instruments [Abstract]  
Credit Facilities
At March 31, 2022, NSP-Minnesota had the following committed revolving credit facility available (in millions of dollars):
Credit Facility (a)
Drawn (b)
Available
$500 $11 $489 
(a)Expires in June 2024.
(b)Includes outstanding commercial paper and letters of credit.
Money Pool  
Borrowings and Other Financing Instruments [Abstract]  
Short-Term Borrowings
Money pool borrowings for NSP-Minnesota:
(Amounts in Millions, Except Interest Rates)Three Months Ended March 31, 2022Year Ended Dec. 31, 2021
Borrowing limit$250 $250 
Amount outstanding at period end— — 
Average amount outstanding— 6 
Maximum amount outstanding— 236 
Weighted average interest rate, computed on a daily basisN/A0.07 %
Weighted average interest rate at period endN/AN/A
Commercial Paper  
Borrowings and Other Financing Instruments [Abstract]  
Short-Term Borrowings Commercial paper outstanding for NSP-Minnesota:
(Amounts in Millions, Except Interest Rates)Three Months Ended March 31, 2022Year Ended Dec. 31, 2021
Borrowing limit$500 $500 
Amount outstanding at period end— — 
Average amount outstanding4 26 
Maximum amount outstanding50 317 
Weighted average interest rate, computed on a daily basis0.15 %0.18 %
Weighted average interest rate at period endN/AN/A
Bilateral Credit Agreement | Letter of Credit  
Borrowings and Other Financing Instruments [Abstract]  
Short-Term Borrowings
As of March 31, 2022, NSP-Minnesota’s outstanding letters of credit under the bilateral credit agreement were as follows:
(Millions of Dollars)LimitAmount OutstandingAvailable
NSP-Minnesota$75 $45 $30 
v3.22.1
Revenues (Tables)
 3 Months Ended
Mar. 31, 2022
Revenue from Contract with Customer [Abstract]  
Disaggregation of Revenue NSP-Minnesota’s operating revenues consisted of the following:
Three Months Ended March 31, 2022
(Millions of Dollars)ElectricNatural GasAll OtherTotal
Major revenue types
Revenue from contracts with customers:
Residential$337 $235 $6 $578 
C&I514 180 — 694 
Other9 — 4 13 
Total retail860 415 10 1,285 
Wholesale124 — — 124 
Transmission61 — — 61 
Interchange129 — — 129 
Other6 2 — 8 
Total revenue from contracts with customers1,180 417 10 1,607 
Alternative revenue and other74 17 — 91 
Total revenues$1,254 $434 $10 $1,698 
Three Months Ended March 31, 2021
(Millions of Dollars)ElectricNatural GasAll OtherTotal
Major revenue types
Revenue from contracts with customers:
Residential$326 $114 $7 $447 
C&I416 79 — 495 
Other8 — 2 10 
Total retail750 193 9 952 
Wholesale98 — — 98 
Transmission57 — — 57 
Interchange115 — — 115 
Other2 — — 2 
Total revenue from contracts with customers1,022 193 9 1,224 
Alternative revenue and other117 11 — 128 
Total revenues$1,139 $204 $9 $1,352 
v3.22.1
Income Taxes (Tables)
 3 Months Ended
Mar. 31, 2022
Income Tax Disclosure [Abstract]  
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
Difference between the statutory rate and ETR:
Three Months Ended March 31
20222021
Federal statutory rate21.0 %21.0 %
State tax (net of federal tax effect)7.0 7.0 
Increases (decreases) in tax from:
Wind PTCs(68.6)(30.4)
Plant regulatory differences (a)
(5.7)(7.8)
Other tax credits, net operating loss & tax credit allowances(1.4)(1.3)
Other (net)1.7 1.2 
Effective income tax rate(46.0)%(10.3)%
(a)Regulatory differences for income tax primarily relate to the credit of excess deferred taxes to customers through the average rate assumption method. Income tax benefits associated with the credit of excess deferred credits are offset by corresponding revenue reductions.
v3.22.1
Fair Value of Financial Assets and Liabilities (Tables)
 3 Months Ended
Mar. 31, 2022
Fair Value Disclosures [Abstract]  
Cost and Fair Value of Nuclear Decommissioning Fund Investments
Non-derivative instruments with recurring fair value measurements in the nuclear decommissioning fund:
March 31, 2022
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3NAVTotal
Nuclear decommissioning fund (a)
Cash equivalents$80 $80 $— $— $— $80 
Commingled funds871 — — — 1,258 1,258 
Debt securities626 — 606 10 — 616 
Equity securities409 1,159 1 — — 1,160 
Total$1,986 $1,239 $607 $10 $1,258 $3,114 
(a)Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $53 million of rabbi trust assets and other miscellaneous investments.
Dec. 31, 2021
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3NAVTotal
Nuclear decommissioning fund (a)
Cash equivalents$64 $64 $— $— $— $64 
Commingled funds856 — — — 1,294 1,294 
Debt securities631 — 666 9 — 675 
Equity securities411 1,222 1 — — 1,223 
Total$1,962 $1,286 $667 $9 $1,294 $3,256 
(a)Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $52 million of rabbi trust assets and miscellaneous investments.
Final Contractual Maturity Dates of Debt Securities in the Nuclear Decommissioning Fund by Asset Class
Contractual maturity dates of debt securities in the nuclear decommissioning fund as of March 31, 2022:
Final Contractual Maturity
(Millions of Dollars)Due in 1 year or LessDue in 1 to 5 YearsDue in 5 to 10 YearsDue after 10 YearsTotal
Debt securities$2 $142 $193 $279 $616 
Rabbi Trust Securities Amortized Cost and Fair Value Measured on Recurrring Basis [Table Text Block]
Cost and fair value of assets held in rabbi trusts:
March 31, 2022
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3Total
Rabbi Trusts (a)
Mutual funds$10 $12 $— $— $12 
Total$10 $12 $— $— $12 
Dec. 31, 2021
Fair Value
(Millions of Dollars)CostLevel 1Level 2Level 3Total
Rabbi Trusts (a)
Mutual funds$10 $13 $— $— $13 
Total$10 $13 $— $— $13 
(a)    Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets.
Gross Notional Amounts of Commodity Forwards, Options, and FTRs
Gross notional amounts of commodity forwards, options and FTRs:
(Amounts in Millions) (a)(b)
March 31, 2022Dec. 31, 2021
Megawatt hours of electricity40 57 
Million British thermal units of natural gas86 85 
(a)Amounts are not reflective of net positions in the underlying commodities.
(b)Notional amounts for options are included on a gross basis, but are weighted for the probability of exercise.
Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income mpact of Derivative Activity —
Pre-Tax Fair Value Gains (Losses) Recognized During the Period in:
(Millions of Dollars)Accumulated Other Comprehensive LossRegulatory (Assets) and Liabilities
Three Months Ended March 31, 2022
Other derivative instruments
Natural gas commodity$— $2 
Total$— $2 
Three Months Ended March 31, 2021
Other derivative instruments
Natural gas commodity$— $1 
Total$— $1 

Pre-Tax (Gains) Losses Reclassified into Income During the Period from:Pre-Tax Gains (Losses) Recognized During the Period in Income
(Millions of Dollars)Accumulated Other Comprehensive LossRegulatory Assets and (Liabilities)
Three Months Ended March 31, 2022
Other derivative instruments
Commodity trading$— $— $1 
(a)
Electric commodity— (1)
(b)
— 
Natural gas commodity— 1 
(c)
(5)
(c)(d)
Total$— $— $(4)
Pre-Tax (Gains) Losses Reclassified
into Income During the Period from:		Pre-Tax Gains (Losses)
Recognized
During the Period in Income
(Millions of Dollars)Accumulated Other Comprehensive LossRegulatory
Assets and (Liabilities)
Three Months Ended March 31, 2021
Other derivative instruments
Commodity trading$— $— $31 
(a)
Electric commodity— (1)
(b)
— 
Natural gas commodity— 1 
(c)
(3)
(c)(d)
Total$— $— $28 
(a)Recorded to electric operating revenues. Portions of these gains and losses are subject to sharing with electric customers through margin-sharing mechanisms and deducted from gross revenue, as appropriate.
(b)Recorded to electric fuel and purchased power. These derivative settlement gains and losses are shared with electric customers through fuel and purchased energy cost-recovery mechanisms, and reclassified out of income as regulatory assets or liabilities, as appropriate.
(c)Settlement losses related to natural gas operations are recorded to cost of natural gas sold and transported. These losses are subject to cost-recovery mechanisms and reclassified out of income to a regulatory asset, as appropriate.
(d)Relates primarily to option premium amortization.
Derivative Assets and Liabilities Measured at Fair Value on a Recurring Basis by Hierarchy Level
Recurring Fair Value Measurements — NSP-Minnesota’s derivative assets and liabilities measured at fair value on a recurring basis were as follows:
March 31, 2022Dec. 31, 2021
Fair ValueFair Value Total
Netting (a)
TotalFair ValueFair Value Total
Netting (a)
Total
(Millions of Dollars)Level 1Level 2Level 3Level 1Level 2Level 3
Current derivative assets
Other derivative instruments:
Commodity trading$26 $76 $53 $155 $(114)$41 $9 $40 $22 $71 $(53)$18 
Electric commodity— — 10 10 — 10 — — 30 30 (1)29 
Natural gas commodity— — — — — — — 6 — 6 — 6 
Total current derivative assets$26 $76 $63 $165 $(114)51 $9 $46 $52 $107 $(54)53 
PPAs (b)
2 — 
Current derivative instruments$53 $53 
Noncurrent derivative assets
Other derivative instruments:
Commodity trading$17 $42 $63 $122 $(62)$60 $6 $34 $35 $75 $(42)$33 
Total noncurrent derivative assets$17 $42 $63 $122 $(62)$60 $6 $34 $35 $75 $(42)$33 
March 31, 2022Dec. 31, 2021
Fair ValueFair Value Total
Netting (a)
TotalFair ValueFair Value Total
Netting (a)
Total
(Millions of Dollars)Level 1Level 2Level 3Level 1Level 2Level 3
Current derivative liabilities
Other derivative instruments:
Commodity trading$32 $113 $12 $157 $(114)$43 $13 $58 $4 $75 $(58)$17 
Electric commodity— — 1 1 (1)— — — 1 1 (1)— 
Natural gas commodity— — — — — — — 4 — 4 — 4 
Total current derivative liabilities$32 $113 $13 $158 $(115)43 $13 $62 $5 $80 $(59)21 
PPAs (b)
14 14 
Current derivative instruments$57 $35 
Noncurrent derivative liabilities
Other derivative instruments:
Commodity trading$34 $63 $37 $134 $(86)$48 $15 $48 $26 $89 $(53)$36 
Total noncurrent derivative liabilities$34 $63 $37 $134 $(86)48 $15 $48 $26 $89 $(53)36 
PPAs (b)
33 35 
Noncurrent derivative instruments$81 $71 
(a)NSP-Minnesota nets derivative instruments and related collateral on its consolidated balance sheets when supported by a legally enforceable master netting agreement, and all derivative instruments and related collateral amounts were subject to master netting agreements at March 31, 2022 and Dec. 31, 2021. At both March 31, 2022 and Dec. 31, 2021, derivative assets and liabilities include $15 million of obligations to return cash collateral. At March 31, 2022 and Dec. 31, 2021 derivative assets and liabilities include rights to reclaim cash collateral of $24 million and $16 million, respectively. The counterparty netting excludes settlement receivables and payables and non-derivative amounts that may be subject to the same master netting agreements.
(b)During 2006, Xcel Energy qualified these contracts under the normal purchase exception. Based on this qualification, the contracts are no longer adjusted to fair value and the previous carrying value of these contracts will be amortized over the remaining contract lives along with the offsetting regulatory assets and liabilities.
Changes in Level 3 Commodity Derivatives
Changes in Level 3 commodity derivatives for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31
(Millions of Dollars)20222021
Balance at Jan 1$56 $(11)
Settlements(19)(7)
Net transactions recorded during the period:
Gains recognized in earnings (a)
49 30 
Net losses recognized as regulatory assets and liabilities(10)— 
Balance at March 31$76 $12 
(a)Level 3 net gains recognized in earnings are subject to offsetting net losses of derivative instruments categorized as levels 1 and 2 in the income statement.
Carrying Amount and Fair Value of Long-term Debt
Other financial instruments for which the carrying amount did not equal fair value:
March 31, 2022Dec. 31, 2021
(Millions of Dollars)Carrying AmountFair ValueCarrying AmountFair Value
Long-term debt, including current portion$6,749 $6,984 $6,747 $7,761 
v3.22.1
Benefit Plans and Other Postretirement Benefits (Tables)
 3 Months Ended
Mar. 31, 2022
Retirement Benefits [Abstract]  
Components of Net Periodic Benefit Cost (Credit)
Components of Net Periodic Benefit Cost
Three Months Ended March 31
2022202120222021
(Millions of Dollars)Pension BenefitsPostretirement Health
Care Benefits
Service cost$7 $7 $— $— 
Interest cost (a)
6 6 1 1 
Expected return on plan assets (a)
(12)(13)— — 
Amortization of prior service credit (a)
— — (1)(1)
Amortization of net loss (a)
6 9 — — 
Settlement charge (b)
(1)— — — 
Net periodic benefit cost6 9 — — 
Effects of regulation1 (1)— — 
Net benefit cost recognized for financial reporting$7 $8 $— $— 
(a)     The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.
(b)     In the first quarter of 2022, NSP-Minnesota recognized $1 million in settlement charge true-ups related to fourth quarter 2021.
 [1]
[1] The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.
v3.22.1
Commitment and Contingencies (Tables)
 3 Months Ended
Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]  
Lease, Cost
Components of lease expense:
Three Months Ended March 31
(Millions of Dollars)20222021
Operating leases
PPA capacity payments$24 $19 
Other operating leases (a)
32
Total operating lease expense (b)
$27 $21 
(a)Includes immaterial short-term lease expense for 2022 and 2021.
(b)PPA capacity payments are included in electric fuel and purchased power on the consolidated statements of income. Expense for other operating leases is included in O&M expense and electric fuel and purchased power.
Lessee, Operating Lease, Liability, Maturity
Commitments under operating leases as of March 31, 2022:
(Millions of Dollars)PPA Operating
Leases
Other Operating
Leases
Total
Operating
Leases
Total minimum obligation$390 $71 $461 
Interest component of obligation(28)(12)(40)
Present value of minimum obligation$362 $59 421 
Less current portion(95)
Noncurrent operating lease liabilities$326 
v3.22.1
Other Comprehensive Income (Loss) (Tables)
 3 Months Ended
Mar. 31, 2022
Stockholders' Equity Note [Abstract]  
Changes in Accumulated Other Comprehensive Income (Loss), Net of Tax
Changes in accumulated other comprehensive income (loss), net of tax, for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31, 2022Three Months Ended March 31, 2021
(Millions of Dollars)Gains and Losses on Cash Flow HedgesDefined Benefit Pension and Postretirement ItemsTotalGains and Losses on Cash Flow HedgesDefined Benefit Pension and Postretirement ItemsTotal
Accumulated other comprehensive loss at Jan. 1$(17)$(3)$(20)$(19)$(3)$(22)
Losses reclassified from net accumulated other comprehensive loss:
Interest rate derivatives, net of taxes of $— and $—, respectively (a)
— — — 1 — 1 
Accumulated other comprehensive loss at March 31$(17)$(3)$(20)$(18)$(3)$(21)
(a)Included in interest charges.
v3.22.1
Segment Information (Tables)
 3 Months Ended
Mar. 31, 2022
Segment Reporting [Abstract]  
Results from Operations by Reportable Segment
NSP-Minnesota’s segment information:
Three Months Ended March 31
(Millions of Dollars)20222021
Regulated Electric
Total revenues (a)
$1,254 $1,139 
Net income98 107 
Regulated Natural Gas
   Total revenues(b)
$434 $204 
Net income29 20 
All Other
Total revenues$10 $9 
Net income— 1 
Consolidated Total
Total revenues (a)(b)
$1,698 $1,352 
Net income127 128 
(a)    Operating revenues include $129 million and $115 million of affiliate electric revenue for the three months ended March 31, 2022 and 2021.
(b)    Operating revenues include an immaterial amount of affiliate gas revenue for the three months ended March 31, 2022 and 2021.
v3.22.1
Accounts Receivable (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Balance Sheet Related Disclosures [Abstract]    
Accounts Receivable $ 546 $ 474
Less allowance for bad debts (49) (45)
Accounts receivable, net $ 497 $ 429
v3.22.1
Inventories (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Public Utilities, Inventory [Line Items]    
Inventories $ 250 $ 309
Materials and supplies    
Public Utilities, Inventory [Line Items]    
Inventories 184 181
Fuel    
Public Utilities, Inventory [Line Items]    
Inventories 58 81
Natural Gas    
Public Utilities, Inventory [Line Items]    
Inventories $ 8 $ 47
v3.22.1
Property, Plant and Equipment (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Public Utility, Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Gross $ 24,007 $ 23,728
Accumulated depreciation and amortization (7,768) (7,606)
Property, plant and equipment, net 16,521 16,430
Electric plant    
Public Utility, Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Gross 19,676 19,154
Natural gas plant    
Public Utility, Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Gross 1,917 1,864
Common and other property    
Public Utility, Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Gross 1,056 1,007
Plant to be Retired (a)    
Public Utility, Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Gross [1] 700 719
Construction work in progress    
Public Utility, Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Gross 658 984
Nuclear fuel    
Public Utility, Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Gross 3,085 3,081
Accumulated depreciation and amortization $ (2,803) $ (2,773)
[1] Includes regulator-approved retirements of Sherco Units 1, 2 and 3 and A.S. King.
v3.22.1
Money Pool (Details) - Money Pool - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Short-term Debt [Line Items]    
Borrowing limit $ 250 $ 250
Amount outstanding at period end 0 0
Average amount outstanding 0 6
Maximum amount outstanding $ 0 $ 236
Weighted average interest rate, computed on a daily basis   0.07%
v3.22.1
Borrowings and Other Financing Instruments Commercial Paper (Details) - Commercial Paper - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Short-term Debt [Line Items]    
Borrowing limit $ 500 $ 500
Amount outstanding at period end 0 0
Average amount outstanding 4 26
Maximum amount outstanding $ 50 $ 317
Weighted average interest rate, computed on a daily basis 0.15% 0.18%
v3.22.1
Letters of Credit (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Letter of Credit    
Line of Credit Facility [Line Items]    
Direct advances on the credit facility outstanding $ 11 $ 9
v3.22.1
Credit Facility (Details) - Credit Facility
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Line of Credit Facility [Line Items]    
Borrowing limit [1] $ 500  
Amount outstanding at period end [2] $ 11  
Number of extension you can request 2  
Available $ 489  
Direct advances on the credit facility outstanding $ 0 $ 0
[1] Expires in June 2024.
[2] Includes outstanding commercial paper and letters of credit.
v3.22.1
Bilateral Credit Agreement (Details) - Letter of Credit - Bilateral Credit Agreement
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
Short-term Debt [Line Items]  
Borrowing Limit $ 75
Amount outstanding at period end 45
Available $ 30
NSP Minnesota [Member]  
Short-term Debt [Line Items]  
Debt Instrument, Term 1 year
v3.22.1
Revenues (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Total revenues    
Disaggregation of Revenue [Line Items]    
Total revenues $ 1,698 $ 1,352
Regulated Electric | Total revenues    
Disaggregation of Revenue [Line Items]    
Total revenues 1,254 1,139
Regulated Natural Gas | Total revenues    
Disaggregation of Revenue [Line Items]    
Total revenues 434 204
All Other | Total revenues    
Disaggregation of Revenue [Line Items]    
Total revenues 10 9
Retail    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 1,285 952
Retail | Residential    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 578 447
Retail | C&I    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 694 495
Retail | Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 13 10
Retail | Regulated Electric    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 860 750
Retail | Regulated Electric | Residential    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 337 326
Retail | Regulated Electric | C&I    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 514 416
Retail | Regulated Electric | Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 9 8
Retail | Regulated Natural Gas    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 415 193
Retail | Regulated Natural Gas | Residential    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 235 114
Retail | Regulated Natural Gas | C&I    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 180 79
Retail | Regulated Natural Gas | Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Retail | All Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 10 9
Retail | All Other | Residential    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 6 7
Retail | All Other | C&I    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Retail | All Other | Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 4 2
Wholesale    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 124 98
Wholesale | Regulated Electric    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 124 98
Wholesale | Regulated Natural Gas    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Wholesale | All Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Transmission    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 61 57
Transmission | Regulated Electric    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 61 57
Transmission | Regulated Natural Gas    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Transmission | All Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Interchange    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 129 115
Interchange | Regulated Electric    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 129 115
Interchange | Regulated Natural Gas    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Interchange | All Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 8 2
Other | Regulated Electric    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 6 2
Other | Regulated Natural Gas    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 2 0
Other | All Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 0 0
Total revenue from contracts with customers    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 1,607 1,224
Total revenue from contracts with customers | Regulated Electric    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 1,180 1,022
Total revenue from contracts with customers | Regulated Natural Gas    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 417 193
Total revenue from contracts with customers | All Other    
Disaggregation of Revenue [Line Items]    
Revenue from contract with customer 10 9
Alternative revenue and other    
Disaggregation of Revenue [Line Items]    
Alternative revenue and other 91 128
Alternative revenue and other | Regulated Electric    
Disaggregation of Revenue [Line Items]    
Alternative revenue and other 74 117
Alternative revenue and other | Regulated Natural Gas    
Disaggregation of Revenue [Line Items]    
Alternative revenue and other 17 11
Alternative revenue and other | All Other    
Disaggregation of Revenue [Line Items]    
Alternative revenue and other $ 0 $ 0
v3.22.1
Income Taxes (Details)
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Income Tax Disclosure [Abstract]    
Federal statutory rate 21.00% 21.00%
State tax (net of federal tax effect) 7.00% 7.00%
Wind PTCs (68.60%) (30.40%)
Plant regulatory differences [1] (5.70%) (7.80%)
Other tax credits, net operating loss & tax credit allowances (1.40%) (1.30%)
Other (net) 1.70% 1.20%
Effective income tax rate (46.00%) (10.30%)
[1] Regulatory differences for income tax primarily relate to the credit of excess deferred taxes to customers through the average rate assumption method. Income tax benefits associated with the credit of excess deferred credits are offset by corresponding revenue reductions.
v3.22.1
Non-Derivative Fair Value Measurements (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Miscellaneous investments $ 53 $ 52
Debt Securities, Available-for-sale, Unrealized Gain 1,200 1,300
Debt Securities, Available-for-sale, Unrealized Loss 37 7
Final Contractual Maturity [Abstract]    
Due in 1 Year or Less 2  
Due in 1 to 5 Years 142  
Due in 5 to 10 Years 193  
Due after 10 Years 279  
Total 616  
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Cost    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total 1,986 [1] 1,962 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Cost | Cash equivalents    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 80 [1] 64 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Cost | Commingled funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Commingled funds 871 [1] 856 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Cost | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Debt securities 626 [1] 631 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Cost | Equity securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity securities 409 [1] 411 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total 3,114 [1] 3,256 [2]
NAV 1,258 [1] 1,294 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Cash equivalents    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 80 [1] 64 [2]
NAV 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Commingled funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Commingled funds 1,258 [1] 1,294 [2]
NAV 1,258 [1] 1,294 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Debt securities 616 [1] 675 [2]
NAV 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Equity securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity securities 1,160 [1] 1,223 [2]
NAV 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total 1,239 [1] 1,286 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Cash equivalents    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 80 [1] 64 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Commingled funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Commingled funds 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Debt securities 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 1 | Equity securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity securities 1,159 [1] 1,222 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total 607 [1] 667 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Cash equivalents    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Commingled funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Commingled funds 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Debt securities 606 [1] 666 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 2 | Equity securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity securities 1 [1] 1 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total 10 [1] 9 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Cash equivalents    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Commingled funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Commingled funds 0 [1] 0 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Debt securities 10 [1] 9 [2]
Nuclear Decommissioning Fund | Fair Value Measured on a Recurring Basis | Fair Value | Level 3 | Equity securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity securities $ 0 [1] $ 0 [2]
[1] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $53 million of rabbi trust assets and other miscellaneous investments.
[2] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets, which also includes $52 million of rabbi trust assets and miscellaneous investments.
v3.22.1
Rabbi Trust (Details) - Rabbi Trust [Member] - Fair Value Measured on a Recurring Basis - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Cost    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total [1] $ 10 $ 10
Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total [1] 12 13
Mutual Fund | Cost    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Mutual funds [1] 10 10
Mutual Fund | Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Mutual funds [1] 12 13
Level 1 | Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total [1] 12 13
Level 1 | Mutual Fund | Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Mutual funds [1] 12 13
Level 2 | Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total [1] 0 0
Level 2 | Mutual Fund | Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Mutual funds [1] 0 0
Level 3 | Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total [1] 0 0
Level 3 | Mutual Fund | Estimate of Fair Value Measurement [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Mutual funds [1] $ 0 $ 0
[1] Reported in nuclear decommissioning fund and other investments on the consolidated balance sheets.
v3.22.1
Interest Rate Derivative (Details) - Interest Rate Derivatives
$ in Millions
Mar. 31, 2022
USD ($)
Interest Rate Derivatives [Abstract]  
Amount or interest rate derivatives expected to be reclassified $ 1
Derivative Liability, Notional Amount $ 0
v3.22.1
Commodity Derivatives (Details)
MWh in Millions, MMBTU in Millions, $ in Millions
Mar. 31, 2022
USD ($)
MWh
MMBTU
Dec. 31, 2021
USD ($)
MMBTU
MWh
Gross Notional Amounts of Commodity Forwards, Options and FTRs [Abstract]    
Miscellaneous investments $ 53 $ 52
Cash flow hedge commodity    
Derivative [Line Items]    
Commodity contracts designated as cash flow hedges $ 0  
Electric commodity    
Gross Notional Amounts of Commodity Forwards, Options and FTRs [Abstract]    
Derivative, Nonmonetary Notional amount | MWh [1],[2] 40 57
Natural Gas Commodity    
Gross Notional Amounts of Commodity Forwards, Options and FTRs [Abstract]    
Derivative, Nonmonetary Notional amount | MMBTU [1],[2] 86 85
[1] Amounts are not reflective of net positions in the underlying commodities.
[2] Notional amounts for options are included on a gross basis, but are weighted for the probability of exercise.
v3.22.1
Consideration of Credit Risk and Concentrations (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
Counterparty
Mar. 31, 2021
USD ($)
Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income [Abstract]    
Fair Value Hedges, Net $ 0 $ 0
Other Derivative Instruments    
Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income [Abstract]    
Pre-tax fair value gains (losses) recognized during the period in accumulated other comprehensive loss 0 0
Pre-tax fair value gains (losses) recognized during the period in regulatory (assets) and liabilities 2 1
Pre-tax (gains) losses reclassified into income during the period from accumulated other comprehensive loss 0 0
Pre-tax (gains) losses reclassified into income during the period from regulatory assets and (liabilities) 0 0
Pre-tax gains (losses) recognized during the period in income (4) 28
Commodity Trading Contract | Other Derivative Instruments    
Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income [Abstract]    
Pre-tax (gains) losses reclassified into income during the period from accumulated other comprehensive loss 0 0
Pre-tax (gains) losses reclassified into income during the period from regulatory assets and (liabilities) 0 0
Pre-tax gains (losses) recognized during the period in income [1] 1 31
Electric Commodity | Other Derivative Instruments    
Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income [Abstract]    
Pre-tax (gains) losses reclassified into income during the period from accumulated other comprehensive loss 0 0
Pre-tax (gains) losses reclassified into income during the period from regulatory assets and (liabilities) [2] (1) (1)
Pre-tax gains (losses) recognized during the period in income 0 0
Natural Gas Commodity | Other Derivative Instruments    
Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income [Abstract]    
Pre-tax (gains) losses reclassified into income during the period from accumulated other comprehensive loss 0 0
Pre-tax (gains) losses reclassified into income during the period from regulatory assets and (liabilities) [3] 1 1
Pre-tax gains (losses) recognized during the period in income [3],[4] (5) (3)
Natural gas commodity | Other Derivative Instruments    
Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income [Abstract]    
Pre-tax fair value gains (losses) recognized during the period in accumulated other comprehensive loss 0 0
Pre-tax fair value gains (losses) recognized during the period in regulatory (assets) and liabilities $ 2 $ 1
Credit Concentration Risk    
Derivative [Line Items]    
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 10  
Credit Concentration Risk | Municipal or Cooperative Entities or Other Utilities [Member]    
Derivative [Line Items]    
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 4  
Credit Concentration Risk | External Credit Rating, Investment Grade [Member]    
Derivative [Line Items]    
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 7  
Wholesale, trading and non trading commodity credit exposure for the most significant counterparties $ 46  
Percentage of wholesale, trading and non trading commodity credit exposure for the most significant counterparties 48.00%  
Credit Concentration Risk | Internal Investment Grade [Member]    
Derivative [Line Items]    
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 1  
Wholesale, trading and non trading commodity credit exposure for the most significant counterparties $ 21  
Percentage of wholesale, trading and non trading commodity credit exposure for the most significant counterparties 22.00%  
Credit Concentration Risk | External Credit Rating, Non Investment Grade [Member]    
Derivative [Line Items]    
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 2  
Wholesale, trading and non trading commodity credit exposure for the most significant counterparties $ 27  
Percentage of wholesale, trading and non trading commodity credit exposure for the most significant counterparties 28.00%  
[1] Recorded to electric operating revenues. Portions of these gains and losses are subject to sharing with electric customers through margin-sharing mechanisms and deducted from gross revenue, as appropriate.
[2] Recorded to electric fuel and purchased power. These derivative settlement gains and losses are shared with electric customers through fuel and purchased energy cost-recovery mechanisms, and reclassified out of income as regulatory assets or liabilities, as appropriate.
[3] Settlement losses related to natural gas operations are recorded to cost of natural gas sold and transported. These losses are subject to cost-recovery mechanisms and reclassified out of income to a regulatory asset, as appropriate.
[4] Relates primarily to option premium amortization.
v3.22.1
Credit Related Contingent Features (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
Counterparty
Mar. 31, 2021
USD ($)
Dec. 31, 2021
USD ($)
Fair Value Disclosures [Abstract]      
Derivative instruments in a gross liability position $ 4   $ 3
Derivative, Gross Liability with Cross Default Position, Aggregate Fair Value 83   48
Collateral posted related to adequate assurance clauses in derivative contracts 0   0
Derivative [Line Items]      
Fair Value Hedges, Net 0 $ 0  
Derivative instruments in a gross liability position 4   3
Derivative, Gross Liability with Cross Default Position, Aggregate Fair Value $ 83   $ 48
Credit Concentration Risk      
Derivative [Line Items]      
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 10    
Credit Concentration Risk | Municipal or Cooperative Entities or Other Utilities [Member]      
Derivative [Line Items]      
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 4    
External Credit Rating, Investment Grade [Member] | Credit Concentration Risk      
Derivative [Line Items]      
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 7    
Wholesale, trading and non trading commodity credit exposure for the most significant counterparties $ 46    
Percentage of wholesale, trading and non trading commodity credit exposure for the most significant counterparties 48.00%    
Internal Investment Grade [Member] | Credit Concentration Risk      
Derivative [Line Items]      
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 1    
Wholesale, trading and non trading commodity credit exposure for the most significant counterparties $ 21    
Percentage of wholesale, trading and non trading commodity credit exposure for the most significant counterparties 22.00%    
External Credit Rating, Non Investment Grade [Member] | Credit Concentration Risk      
Derivative [Line Items]      
Number of most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure | Counterparty 2    
Wholesale, trading and non trading commodity credit exposure for the most significant counterparties $ 27    
Percentage of wholesale, trading and non trading commodity credit exposure for the most significant counterparties 28.00%    
Other Derivative Instruments      
Derivative [Line Items]      
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net $ 0 0  
Pre-tax gains (losses) reclassified into income during the period from regulatory assets and (liabilities) 0 0  
Pre-tax gains (losses) recognized during the period in income (4) 28  
Pre-tax fair value gains (losses) recognized during the period in accumulated other comprehensive loss 0 0  
Pre-tax fair value gains (losses) recognized during the period in regulatory (assets) and liabilities 2 1  
Commodity Trading Contract | Other Derivative Instruments      
Derivative [Line Items]      
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net 0 0  
Pre-tax gains (losses) reclassified into income during the period from regulatory assets and (liabilities) 0 0  
Pre-tax gains (losses) recognized during the period in income [1] 1 31  
Electric Commodity | Other Derivative Instruments      
Derivative [Line Items]      
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net 0 0  
Pre-tax gains (losses) reclassified into income during the period from regulatory assets and (liabilities) [2] 1 1  
Pre-tax gains (losses) recognized during the period in income 0 0  
Natural Gas Commodity | Other Derivative Instruments      
Derivative [Line Items]      
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net 0 0  
Pre-tax gains (losses) reclassified into income during the period from regulatory assets and (liabilities) [3] (1) (1)  
Pre-tax gains (losses) recognized during the period in income [3],[4] (5) (3)  
Natural gas commodity | Other Derivative Instruments      
Derivative [Line Items]      
Pre-tax fair value gains (losses) recognized during the period in accumulated other comprehensive loss 0 0  
Pre-tax fair value gains (losses) recognized during the period in regulatory (assets) and liabilities $ 2 $ 1  
[1] Recorded to electric operating revenues. Portions of these gains and losses are subject to sharing with electric customers through margin-sharing mechanisms and deducted from gross revenue, as appropriate.
[2] Recorded to electric fuel and purchased power. These derivative settlement gains and losses are shared with electric customers through fuel and purchased energy cost-recovery mechanisms, and reclassified out of income as regulatory assets or liabilities, as appropriate.
[3] Settlement losses related to natural gas operations are recorded to cost of natural gas sold and transported. These losses are subject to cost-recovery mechanisms and reclassified out of income to a regulatory asset, as appropriate.
[4] Relates primarily to option premium amortization.
v3.22.1
Recurring Fair Value Measurements (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Derivatives, Fair Value [Line Items]      
Obligation to return cash $ 15   $ 15
Right to reclaim cash 24   16
Commodity Trading      
Changes in Level 3 Commodity Derivatives [Roll Forward]      
Balance at beginning of period 56 $ (11)  
Settlements (19) (7)  
Gains (losses) recognized in earnings [1] 49 30  
Net gains recognized as regulatory assets and liabilities (10) 0  
Balance at end of period 76 12  
Other Current Assets      
Derivatives, Fair Value [Line Items]      
Derivative asset 53   53
Other Current Liabilities      
Derivatives, Fair Value [Line Items]      
Derivative liability 57   35
Other Noncurrent Liabilities      
Derivatives, Fair Value [Line Items]      
Derivative liability 81   71
Fair Value Measured on a Recurring Basis | Level 3      
Changes in Level 3 Commodity Derivatives [Roll Forward]      
Transfers level 3, net 0 $ 0  
Fair Value Measured on a Recurring Basis | Other Current Assets      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 165   107
Netting, asset [2] (114)   (54)
Derivative asset 51   53
Fair Value Measured on a Recurring Basis | Other Current Assets | Level 1      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 26   9
Fair Value Measured on a Recurring Basis | Other Current Assets | Level 2      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 76   46
Fair Value Measured on a Recurring Basis | Other Current Assets | Level 3      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 63   52
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 155   71
Netting, asset [2] (114)   (53)
Derivative asset 41   18
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 10   30
Netting, asset [2] 0   (1)
Derivative asset 10   29
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 0   6
Netting, asset [2] 0   0
Derivative asset 0   6
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 1 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 26   9
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 1 | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 0   0
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 1 | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 0   0
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 2 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 76   40
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 2 | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 0   0
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 2 | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 0   6
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 3 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 53   22
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 3 | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 10   30
Fair Value Measured on a Recurring Basis | Other Current Assets | Other Derivative Instruments | Level 3 | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 0   0
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 122   75
Netting, asset [2] (62)   (42)
Derivative asset 60   33
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets | Level 1      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 17   6
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets | Level 2      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 42   34
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets | Level 3      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 63   35
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets | Other Derivative Instruments | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 122   75
Netting, asset [2] (62)   (42)
Derivative asset 60   33
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets | Other Derivative Instruments | Level 1 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 17   6
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets | Other Derivative Instruments | Level 2 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 42   34
Fair Value Measured on a Recurring Basis | Other Noncurrent Assets | Other Derivative Instruments | Level 3 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative asset, gross 63   35
Fair Value Measured on a Recurring Basis | Other Current Liabilities      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 158   80
Netting, liability [2] (115)   (59)
Derivative liability 43   21
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Level 1      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 32   13
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Level 2      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 113   62
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Level 3      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 13   5
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 157   75
Netting, liability [2] (114)   (58)
Derivative liability 43   17
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 1   1
Netting, liability [2] (1)   (1)
Derivative liability 0   0
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 0   4
Netting, liability [2] 0   0
Derivative liability 0   4
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 1 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 32   13
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 1 | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 0   0
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 1 | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 0   0
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 2 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 113   58
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 2 | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 0   0
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 2 | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 0   4
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 3 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 12   4
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 3 | Electric Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 1   1
Fair Value Measured on a Recurring Basis | Other Current Liabilities | Other Derivative Instruments | Level 3 | Natural Gas Commodity      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 0   0
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 134   89
Netting, liability [2] (86)   (53)
Derivative liability 48   36
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities | Level 1      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 34   15
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities | Level 2      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 63   48
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities | Level 3      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 37   26
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities | Other Derivative Instruments | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 134   89
Netting, liability [2] (86)   (53)
Derivative liability 48   36
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities | Other Derivative Instruments | Level 1 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 34   15
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities | Other Derivative Instruments | Level 2 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 63   48
Fair Value Measured on a Recurring Basis | Other Noncurrent Liabilities | Other Derivative Instruments | Level 3 | Commodity Trading      
Derivatives, Fair Value [Line Items]      
Derivative liability, gross 37   26
Fair Value, Measurements, Nonrecurring | Other Current Assets | PPAs      
Derivatives, Fair Value [Line Items]      
Derivative asset [3] 2   0
Fair Value, Measurements, Nonrecurring | Other Current Liabilities | PPAs      
Derivatives, Fair Value [Line Items]      
Derivative liability [3] 14   14
Fair Value, Measurements, Nonrecurring | Other Noncurrent Liabilities | PPAs      
Derivatives, Fair Value [Line Items]      
Derivative liability [3] $ 33   $ 35
[1] Level 3 net gains recognized in earnings are subject to offsetting net losses of derivative instruments categorized as levels 1 and 2 in the income statement.
[2] NSP-Minnesota nets derivative instruments and related collateral on its consolidated balance sheets when supported by a legally enforceable master netting agreement, and all derivative instruments and related collateral amounts were subject to master netting agreements at March 31, 2022 and Dec. 31, 2021. At both March 31, 2022 and Dec. 31, 2021, derivative assets and liabilities include $15 million of obligations to return cash collateral. At March 31, 2022 and Dec. 31, 2021 derivative assets and liabilities include rights to reclaim cash collateral of $24 million and $16 million, respectively. The counterparty netting excludes settlement receivables and payables and non-derivative amounts that may be subject to the same master netting agreements.
[3] During 2006, Xcel Energy qualified these contracts under the normal purchase exception. Based on this qualification, the contracts are no longer adjusted to fair value and the previous carrying value of these contracts will be amortized over the remaining contract lives along with the offsetting regulatory assets and liabilities.
v3.22.1
Fair Value of Long-Term Debt (Details) - USD ($)
$ in Millions
Mar. 31, 2022
Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-term debt, carrying amount $ 6,749 $ 6,747
Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-term Debt, Fair Value $ 6,984 $ 7,761
v3.22.1
Benefit Plans and Other Postretirement Benefits (Details)
$ in Millions
 1 Months Ended 3 Months Ended
Jan. 31, 2022
USD ($)
Plan
Mar. 31, 2022
USD ($)
Mar. 31, 2021
USD ($)
Pension Plan [Member]      
Components of Net Periodic Benefit Cost [Abstract]      
Service Cost   $ 7 $ 7
Interest cost (a) [1]   6 6
Expected return on plan assets (a) [1]   (12) (13)
Amortization of prior service credit (a) [1]   0 0
Amortization of net loss (a) [1]   6 9
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement [2]   (1) 0
Net periodic benefit cost   6 9
Effects of regulation   1 (1)
Net benefit cost recognized for financial reporting   7 8
Total contributions to the pension plans during the period $ 5    
Pension Plan [Member] | Xcel Energy Inc.      
Components of Net Periodic Benefit Cost [Abstract]      
Total contributions to the pension plans during the period $ 50    
Number of Xcel Energy's pension plans to which contributions were made | Plan 4    
Other Postretirement Benefits Plan [Member]      
Components of Net Periodic Benefit Cost [Abstract]      
Service Cost   0 0
Interest cost (a) [1]   1 1
Expected return on plan assets (a) [1]   0 0
Amortization of prior service credit (a) [1]   (1) (1)
Amortization of net loss (a) [1]   0 0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement [2]   0 0
Net periodic benefit cost   0 0
Effects of regulation   0 0
Net benefit cost recognized for financial reporting   $ 0 $ 0
[1] The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.
[2] In the first quarter of 2022, NSP-Minnesota recognized $1 million in settlement charge true-ups related to fourth quarter 2021.
v3.22.1
Commitments and Contingencies - Winter Storm Uri (Details)
$ in Millions
Mar. 31, 2022
USD ($)
Commitments and Contingencies Disclosure [Abstract]  
Winter Storm Uri Costs $ 148
v3.22.1
Commitments and Contingencies - Sherco (Details) - USD ($)
$ in Millions
 1 Months Ended
Jan. 31, 2021
Jan. 27, 2021
Rate Matters [Abstract]    
Customer refund of previously recovered purchased power costs $ 17  
Amount MPUC previously disallowed related to Sherco outage   $ 22
v3.22.1
Commitments and Contingencies - Westmoreland Arbitration (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
Commitments and Contingencies Disclosure [Abstract]  
Gain (Loss) Related to Litigation Settlement $ 36
Westmoreland Recovery $ 19
v3.22.1
Commitments and Contingencies - MISO ROE Complaints (Details) - Federal Energy Regulatory Commission (FERC) - FERC Proceeding, MISO ROE Complaint - NSP Minnesota and NSP Wisconsin [Member] [Member]
 1 Months Ended
Feb. 28, 2015
Nov. 30, 2013
Public Utilities, General Disclosures [Line Items]    
Public Utilities, Base Return On Equity Charged To Customers Through Transmission Formula Rates 1238.00% 1238.00%
Public Utilities, ROE Applicable To Transmission Formula Rates In The MISO Region, Recommended By Third Parties 867.00% 915.00%
v3.22.1
Commitments and Contingencies - Environmental, MGP, Landfill or Disposal Sites (Details)
Mar. 31, 2022
Other MGP, Landfill, or Disposal Sites  
Site Contingency [Line Items]  
Number of identified MGP, landfill, or disposal sites under current investigation and/or remediation 7
v3.22.1
Commitments and Contingencies - Environmental Requirements - Water and Waste (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
Dec. 31, 2022
USD ($)
Plant
Federal Coal Ash Regulation    
Site Contingency [Line Items]    
Number of sites where regulated ash units will still be in operation at a specified date 3  
Number of sites where statistically significant increases over established groundwater standards exist 0  
Number of impoundments where closure plans will be expedited 1  
Estimated cost of closure of an impoundment $ 4  
Time period of existing ash pond closure completion in accordance with the CCR rule 5 years  
Federal Clean Water Act Section 316 (b) | Capital Addition Purchase Commitments    
Site Contingency [Line Items]    
Liability for estimated cost to comply with regulation $ 36  
Liability for estimated cost to comply with entrainment regulation   $ 188
Federal Clean Water Act Section 316 (b) | NSP Minnesota [Member]    
Site Contingency [Line Items]    
Minimum number of plants which could be required to make improvements to reduce entrainment | Plant   6
v3.22.1
Commitments and Contingencies - Leases (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Lessee, Lease, Description [Line Items]      
Operating Lease, Cost [1] $ 27 $ 21  
Lessee, Operating Lease, Liability, to be Paid 461    
Lessee, Operating Lease, Liability, Undiscounted Excess Amount (40)    
Operating Lease, Liability 421    
Operating Lease, Liability, Current (95)   $ (90)
Operating lease liabilities 326   $ 353
Purchased Power Agreements      
Lessee, Lease, Description [Line Items]      
Operating Lease, Cost 24 19  
Lessee, Operating Lease, Liability, to be Paid 390    
Lessee, Operating Lease, Liability, Undiscounted Excess Amount (28)    
Operating Lease, Liability 362    
Property, Plant and Equipment, Other Types      
Lessee, Lease, Description [Line Items]      
Operating Lease, Cost [2] 3 $ 2  
Lessee, Operating Lease, Liability, to be Paid 71    
Lessee, Operating Lease, Liability, Undiscounted Excess Amount (12)    
Operating Lease, Liability $ 59    
[1] PPA capacity payments are included in electric fuel and purchased power on the consolidated statements of income. Expense for other operating leases is included in O&M expense and electric fuel and purchased power.
[2] Includes immaterial short-term lease expense for 2022 and 2021.
v3.22.1
Commitments and Contingencies - Variable Interest Entities (Details) - MW
Mar. 31, 2022
Dec. 31, 2021
Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member]    
Variable Interest Entity [Line Items]    
Generating capacity under long term purchased power agreements 1,322 1,347
v3.22.1
Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive (loss) income at beginning of period $ 7,573  
Accumulated other comprehensive (loss) income at end of period 7,533  
Income Tax Expense (Benefit) (40) $ (12)
Gains and Losses on Cash Flow Hedges    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive (loss) income at beginning of period (17) (19)
Accumulated other comprehensive (loss) income at end of period (17) (18)
Gains and Losses on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Income Tax Expense (Benefit)   0
Gains and Losses on Cash Flow Hedges | Interest Rate Swap [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [1] 0 1
Defined Benefit Pension and Postretirement Items    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive (loss) income at beginning of period (3) (3)
Accumulated other comprehensive (loss) income at end of period (3) (3)
Defined Benefit Pension and Postretirement Items | Reclassification out of Accumulated Other Comprehensive Income [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Income Tax Expense (Benefit)   0
Defined Benefit Pension and Postretirement Items | Interest Rate Swap [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [1] 0 0
Total    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive (loss) income at beginning of period (20) (22)
Accumulated other comprehensive (loss) income at end of period (20) (21)
Total | Interest Rate Swap [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [1] $ 0 $ 1
[1] Included in interest charges
v3.22.1
Segment Information (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Segment Reporting Information [Line Items]    
Net income $ 127 $ 128
Natural gas 434 204
Other 10 9
Regulated and Unregulated Operating Revenue 1,698 1,352
Affiliate Revenue 129 115
Total revenues    
Segment Reporting Information [Line Items]    
Regulated and Unregulated Operating Revenue [1],[2] 1,698 1,352
Regulated Electric    
Segment Reporting Information [Line Items]    
Net income 98 107
Revenues Including Intersegment Revenues [1] 1,254 1,139
Regulated Natural Gas    
Segment Reporting Information [Line Items]    
Net income 29 20
Revenues Including Intersegment Revenues 434 204
All Other    
Segment Reporting Information [Line Items]    
Net income 0 1
All Other | Total revenues    
Segment Reporting Information [Line Items]    
Other $ 10 $ 9
[1] Operating revenues include $129 million and $115 million of affiliate electric revenue for the three months ended March 31, 2022 and 2021.
[2] Operating revenues include an immaterial amount of affiliate gas revenue for the three months ended March 31, 2022 and 2021.