OTTER TAIL CORP, 10-Q filed on 5/4/2022
Quarterly Report
v3.22.1
Cover - shares
 3 Months Ended
Mar. 31, 2022
Apr. 27, 2022
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2022  
Document Transition Report false  
Entity File Number 0-53713  
Entity Registrant Name OTTER TAIL CORPORATION  
Entity Incorporation, State or Country Code MN  
Entity Tax Identification Number 27-0383995  
Entity Address, Address Line One 215 South Cascade Street  
Entity Address, Address Line Two Box 496  
Entity Address, City or Town Fergus Falls  
Entity Address, State or Province MN  
Entity Address, Postal Zip Code 56538-0496  
City Area Code 866  
Local Phone Number 410-8780  
Title of 12(b) Security Common Shares, par value $5.00 per share  
Trading Symbol OTTR  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   41,630,655
Entity Central Index Key 0001466593  
Amendment Flag false  
Document Fiscal Period Focus Q1  
Document Fiscal Year Focus 2022  
Current Fiscal Year End Date --12-31  
v3.22.1
Consolidated Balance Sheets (unaudited) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Current Assets    
Cash and Cash Equivalents $ 1,371 $ 1,537
Receivables, net of allowance for credit losses 218,896 174,953
Inventories 145,857 148,490
Regulatory Assets 21,770 27,342
Other Current Assets 14,497 17,032
Total Current Assets 402,391 369,354
Noncurrent Assets    
Investments 57,893 56,690
Property, Plant and Equipment, net of accumulated depreciation 2,128,344 2,124,605
Regulatory Assets 124,413 125,508
Intangible Assets, net of accumulated amortization 8,768 9,044
Goodwill 37,572 37,572
Other Noncurrent Assets 32,360 32,057
Total Noncurrent Assets 2,389,350 2,385,476
Total Assets 2,791,741 2,754,830
Current Liabilities    
Short-Term Debt 97,770 91,163
Current Maturities of Long-Term Debt 29,990 29,983
Accounts Payable 119,022 135,089
Accrued Salaries and Wages 19,846 31,704
Accrued Taxes 21,879 19,245
Regulatory Liabilities 27,211 24,844
Other Current Liabilities 57,437 55,671
Total Current Liabilities 373,155 387,699
Noncurrent Liabilities    
Pension Benefit Liability 53,153 73,973
Other Postretirement Benefits Liability 66,383 66,481
Regulatory Liabilities 233,989 234,430
Deferred Income Taxes 203,877 188,268
Deferred Tax Credits 16,475 16,661
Other Noncurrent Liabilities 63,497 62,527
Total Noncurrent Liabilities 637,374 642,340
Commitments and Contingencies (Note 9)
Capitalization    
Long-Term Debt, net of current maturities 734,074 734,014
Shareholders' Equity    
Common Shares: 50,000,000 shares authorized, $5 par value; 41,605,884 and 41,551,524 outstanding at March 31, 2022 and December 31, 2021 208,029 207,758
Additional Paid-In Capital 421,449 419,760
Retained Earnings 424,605 369,783
Accumulated Other Comprehensive Loss (6,945) (6,524)
Total Shareholders' Equity 1,047,138 990,777
Total Capitalization 1,781,212 1,724,791
Total Liabilities and Shareholders' Equity $ 2,791,741 $ 2,754,830
v3.22.1
Consolidated Balance Sheets (Parentheticals) - $ / shares
Mar. 31, 2022
Dec. 31, 2021
Shareholders' Equity    
Common stock, shares authorized (in shares) 50,000,000 50,000,000
Common stock, par value (in dollars per share) $ 5 $ 5
Common stock, shares outstanding (in shares) 41,605,884 41,551,524
v3.22.1
Consolidated Statements of Income (unaudited) - USD ($)
shares in Thousands, $ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Revenues    
Total Operating Revenues $ 374,904 $ 261,710
Operating Expenses    
Electric Production Fuel 14,853 14,714
Electric Purchased Power 20,529 19,260
Electric Operating and Maintenance Expenses 44,278 41,421
Cost of Products Sold (excluding depreciation) 151,759 101,977
Other Nonelectric Expenses 17,206 13,693
Depreciation and Amortization 23,548 22,126
Electric Property Taxes 4,432 4,320
Total Operating Expenses 276,605 217,511
Operating Income 98,299 44,199
Other Income and Expense    
Interest Charges 8,948 9,398
Nonservice Cost Components of Postretirement Benefits (22) 383
Other Income (Expense), net 260 1,160
Income Before Income Taxes 89,633 35,578
Income Tax Expense 17,630 5,249
Net Income $ 72,003 $ 30,329
Weighted-Average Common Shares Outstanding:    
Basic (in shares) 41,548 41,455
Diluted (in shares) 41,871 41,700
Earnings Per Share:    
Basic (in dollars per share) $ 1.73 $ 0.73
Diluted (in dollars per share) $ 1.72 $ 0.73
Electric    
Operating Revenues    
Total Operating Revenues $ 130,416 $ 123,699
Product Sales    
Operating Revenues    
Total Operating Revenues $ 244,488 $ 138,011
v3.22.1
Consolidated Statements of Comprehensive Income (unaudited) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Statement of Comprehensive Income [Abstract]    
Net Income $ 72,003 $ 30,329
Other Comprehensive (Loss) Income:    
Unrealized (Loss) on Available-for-Sale Securities, net of tax benefit of $61 and $10 (231) (35)
Pension and Other Postretirement Benefits, net of tax benefit (expense) of $67 and $(53) (190) 150
Total Other Comprehensive (Loss) Income (421) 115
Total Comprehensive Income $ 71,582 $ 30,444
v3.22.1
Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Statement of Comprehensive Income [Abstract]    
Unrealized Gain (Loss) on Available-for-Sale Securities, tax benefit $ 61 $ 10
Pension and Other Postretirement Benefit Plan, tax (expense) benefit $ 67 $ (53)
v3.22.1
Consolidated Statements of Shareholders' Equity (unaudited) - USD ($)
$ in Thousands
Total
Common Shares
Additional Paid-In Capital
Retained Earnings
Accumulated Other Comprehensive Income (Loss)
Beginning balance, shares (in shares) at Dec. 31, 2020   41,469,879      
Beginning balance at Dec. 31, 2020 $ 870,966 $ 207,349 $ 414,246 $ 257,878 $ (8,507)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (in shares)   40,576      
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (1,507) $ 203 (1,710)    
Stock Issued Under Dividend Reinvestment and Stock Purchase Plans, net of expenses and repurchased shares (25)   (25)    
Net Income 30,329     30,329  
Other Comprehensive Income (Loss) 115       115
Stock Compensation Expense 4,197   4,197    
Common Dividends (16,208)     (16,208)  
Ending balance, shares (in shares) at Mar. 31, 2021   41,510,455      
Ending balance at Mar. 31, 2021 887,867 $ 207,552 416,708 271,999 (8,392)
Beginning balance, shares (in shares) at Dec. 31, 2021   41,551,524      
Beginning balance at Dec. 31, 2021 990,777 $ 207,758 419,760 369,783 (6,524)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (in shares)   54,360      
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (2,944) $ 271 (3,215)    
Net Income 72,003     72,003  
Other Comprehensive Income (Loss) (421)       (421)
Stock Compensation Expense 4,904   4,904    
Common Dividends (17,181)     (17,181)  
Ending balance, shares (in shares) at Mar. 31, 2022   41,605,884      
Ending balance at Mar. 31, 2022 $ 1,047,138 $ 208,029 $ 421,449 $ 424,605 $ (6,945)
v3.22.1
Consolidated Statements of Shareholders' Equity (Parentheticals) - $ / shares
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Statement of Stockholders' Equity [Abstract]    
Common Dividends (in dollars per share) $ 0.4125 $ 0.39
v3.22.1
Consolidated Statements of Cash Flows (unaudited) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Operating Activities    
Net Income $ 72,003 $ 30,329
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:    
Depreciation and Amortization 23,548 22,126
Deferred Tax Credits (186) (186)
Deferred Income Taxes 14,342 5,697
Discretionary Contribution to Pension Plan (20,000) (10,000)
Allowance for Equity Funds Used During Construction (260) (45)
Stock Compensation Expense 4,904 4,197
Other, Net 866 (1,407)
Changes in Operating Assets and Liabilities:    
Receivables (43,943) (20,431)
Inventories 3,403 (261)
Regulatory Assets 4,468 703
Other Assets 3,729 (6,421)
Accounts Payable (12,533) 2,245
Accrued and Other Liabilities (7,859) (8,890)
Regulatory Liabilities 2,812 (3,850)
Pension and Other Postretirement Benefits 122 1,464
Net Cash Provided by Operating Activities 45,416 15,270
Investing Activities    
Capital Expenditures (28,710) (50,076)
Proceeds from Disposal of Noncurrent Assets 878 3,244
Cash Used for Investments and Other Assets (3,617) (2,188)
Net Cash Used in Investing Activities (31,449) (49,020)
Financing Activities    
Net Borrowings on Short-Term Debt 6,608 53,854
Payments for Retirement of Long-Term Debt 0 (169)
Dividends Paid (17,181) (16,208)
Payments for Shares Withheld for Employee Tax Obligations (2,942) (1,507)
Other, net (618) (2,171)
Net Cash (Used in) Provided by Financing Activities (14,133) 33,799
Net Change in Cash and Cash Equivalents (166) 49
Cash and Cash Equivalents at Beginning of Period 1,537 1,163
Cash and Cash Equivalents at End of Period $ 1,371 $ 1,212
v3.22.1
Summary of Significant Accounting Policies
 3 Months Ended
Mar. 31, 2022
Accounting Policies [Abstract]  
Summary of Significant Accounting Policies Summary of Significant Accounting Policies
Overview
Otter Tail Corporation (OTC) and its subsidiaries (collectively, the "Company", "us", "our" or "we") form a diverse, multi-platform business consisting of a vertically integrated, regulated utility with generation, transmission and distribution facilities complemented by manufacturing businesses providing metal fabrication for custom machine parts and metal components, manufacturing of extruded and thermoformed plastic products, and manufacturing of polyvinyl chloride (PVC) pipe products. We classify our business into three segments: Electric, Manufacturing and Plastics.
Basis of Presentation
The unaudited consolidated financial statements included herein have been prepared pursuant to the rules and regulations of the SEC for interim reporting. Accordingly, they do not include all the information and footnotes required by generally accepted accounting principles. In the opinion of management, we have included all adjustments, including normal recurring accruals, necessary for a fair presentation of the consolidated financial statements for the periods presented. The consolidated financial statements and condensed notes thereto should be read in conjunction with the consolidated financial statements and notes included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2021.
Because of the seasonality of our businesses and other factors, the earnings for the three months ended March 31, 2022 should not be taken as an indication of earnings for all or any part of the balance of the current year or as an indication of earnings for future years.
Use of Estimates
We use estimates based on the best information available in recording transactions and balances resulting from business operations. As better information becomes available or actual amounts are known, the recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates.
Reclassifications
Certain reclassifications of amounts previously reported have been made to the accompanying consolidated statements of shareholders' equity and consolidated statements of cash flows to maintain consistency and comparability between periods presented. The reclassifications had no impact on previously reported shareholders' equity, net cash provided by operating activities, net cash used in investing activities, net cash (used in) provided by financing activities, or cash and cash equivalents.
v3.22.1
Segment Information
 3 Months Ended
Mar. 31, 2022
Segment Reporting [Abstract]  
Segment Information Segment Information
We classify our business into three segments, Electric, Manufacturing and Plastics, consistent with our business strategy, organizational structure and our internal reporting and review processes used by our chief operating decision maker to make decisions regarding allocation of resources, to assess operating performance and to make strategic decisions.
Certain assets and costs are not allocated to our operating segments. Corporate operating costs include items such as corporate staff and overhead costs, the results of our captive insurance company and other items excluded from the measurement of operating segment performance. Corporate assets consist primarily of cash, prepaid expenses, investments and fixed assets. Corporate is not an operating segment, rather it is added to operating segment totals to reconcile to consolidated amounts.
Information for each segment and our unallocated corporate costs for the three months ended March 31, 2022 and 2021 are as follows:
Three Months Ended March 31,
(in thousands)20222021
Operating Revenue
Electric$130,416 $123,699 
Manufacturing104,957 75,825 
Plastics139,531 62,186 
Total$374,904 $261,710 
Net Income (Loss)
Electric$19,233 $17,587 
Manufacturing4,084 5,385 
Plastics50,846 9,147 
Corporate(2,160)(1,790)
Total$72,003 $30,329 
The following provides the identifiable assets by segment and corporate assets as of March 31, 2022 and December 31, 2021:
(in thousands)March 31,
2022		December 31,
2021
Identifiable Assets
Electric$2,278,337 $2,283,776 
Manufacturing269,833 251,044 
Plastics184,865 162,565 
Corporate58,706 57,445 
Total$2,791,741 $2,754,830 
v3.22.1
Revenue
 3 Months Ended
Mar. 31, 2022
Revenue from Contract with Customer [Abstract]  
Revenue Revenue
We present our operating revenues to external customers, in total and by amounts arising from contracts with customers and alternative revenue program (ARP) arrangements, disaggregated by revenue source and segment for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31,
(in thousands)20222021
Operating Revenues
Electric Segment
Retail: Residential$40,561 $37,485 
Retail: Commercial and Industrial71,171 66,403 
Retail: Other1,907 1,818 
  Total Retail113,639 105,706 
Transmission12,556 11,944 
Wholesale2,463 4,507 
Other1,758 1,542 
Total Electric Segment130,416 123,699 
Manufacturing Segment
Metal Parts and Tooling89,573 62,673 
Plastic Products and Tooling12,445 10,295 
Scrap Metal Sales2,939 2,857 
Total Manufacturing Segment104,957 75,825 
Plastics Segment
PVC Pipe139,531 62,186 
Total Operating Revenue374,904 261,710 
Less: Non-contract Revenues Included Above
Electric Segment - ARP Revenues(2,460)(975)
Total Operating Revenues from Contracts with Customers$377,364 $262,685 
v3.22.1
Select Balance Sheet Information
 3 Months Ended
Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Select Balance Sheet Information Select Balance Sheet Information
Receivables and Allowance for Credit Losses
Receivables as of March 31, 2022 and December 31, 2021 are as follows:
(in thousands)March 31,
2022		December 31,
2021
Receivables
Trade$192,315 $142,297 
Other8,139 10,591 
Unbilled Receivables20,229 23,901 
Total Receivables220,683 176,789 
Less: Allowance for Credit Losses(1,787)(1,836)
Receivables, net of allowance for credit losses$218,896 $174,953 
The following is a summary of activity in the allowance for credit losses for the three months ended March 31, 2022 and 2021:
March 31,March 31,
(in thousands)20222021
Beginning Balance, January 1$1,836 $3,215 
Additions Charged to Expense210 211 
Reductions for Amounts Written Off, Net of Recoveries(259)(443)
Ending Balance, March 31$1,787 $2,983 
Inventories
Inventories consist of the following as of March 31, 2022 and December 31, 2021:
(in thousands)March 31,
2022		December 31,
2021
Finished Goods$37,195 $39,903 
Work in Process33,962 35,705 
Raw Material, Fuel and Supplies74,700 72,882 
Total Inventories$145,857 $148,490 
Investments
The following is a summary of our investments as of March 31, 2022 and December 31, 2021:
(in thousands)March 31,
2022		December 31,
2021
Corporate-Owned Life Insurance Policies$40,722 $41,078 
Debt Securities8,959 9,202 
Money Market Funds1,893 949 
Mutual Funds6,285 5,432 
Other Investments34 29 
Total Investments$57,893 $56,690 
The amount of unrealized gains and losses on debt securities as of March 31, 2022 and December 31, 2021 was not material and no unrealized losses were deemed to be other-than-temporary. In addition, the amount of unrealized gains and losses on marketable equity securities still held as of March 31, 2022 and December 31, 2021 was not material.
Property, Plant and Equipment
Major classes of property, plant and equipment as of March 31, 2022 and December 31, 2021 include:
(in thousands)March 31,
2022		December 31,
2021
Electric Plant  
Electric Plant in Service$2,776,778 $2,758,445 
Construction Work in Progress72,347 74,926 
Total Gross Electric Plant2,849,125 2,833,371 
Less Accumulated Depreciation and Amortization829,499 817,302 
Net Electric Plant2,019,626 2,016,069 
Nonelectric Property, Plant and Equipment
Nonelectric Property, Plant and Equipment in Service278,729 273,950 
Construction Work in Progress14,365 16,611 
Total Gross Nonelectric Property, Plant and Equipment293,094 290,561 
Less Accumulated Depreciation and Amortization184,376 182,025 
Net Nonelectric Property, Plant and Equipment108,718 108,536 
Net Property, Plant and Equipment$2,128,344 $2,124,605 
v3.22.1
Regulatory Matters
 3 Months Ended
Mar. 31, 2022
Regulatory Assets and Liabilities Disclosure [Abstract]  
Regulatory Matters Regulatory Matters
Regulatory Assets and Liabilities
The following presents our current and long-term regulatory assets and liabilities as of March 31, 2022 and December 31, 2021 and the period we expect to recover or refund such amounts:
Period ofMarch 31, 2022December 31, 2021
(in thousands)Recovery/RefundCurrentLong-TermCurrentLong Term
Regulatory Assets
Pension and Other Postretirement Benefit Plans1
Various$7,791 $113,663 $7,791 $114,961 
Alternative Revenue Program Riders2
Up to 2 years
9,280 5,713 11,889 5,564 
Asset Retirement Obligations1
Asset lives— 1,098 — 742 
ISO Cost Recovery Trackers1
Up to 2 years
220 950 — 1,342 
Unrecovered Project Costs1
Up to 5 years
1,086 1,456 2,136 1,455 
Deferred Rate Case Expenses1
Various542 1,037 607 1,131 
Debt Reacquisition Premiums1
Up to 11 years
68 234 100 240 
Fuel Clause Adjustments1
Up to 1 year
2,767 — 4,819 — 
Other1
Various16 262 — 73 
Total Regulatory Assets$21,770 $124,413 $27,342 $125,508 
Regulatory Liabilities
Deferred Income TaxesAsset lives$— $128,042 $— $129,437 
Plant Removal ObligationsAsset lives8,561 101,850 8,306 101,595 
Fuel Clause Adjustments
Up to 1 year
5,386 — 1,554 — 
Alternative Revenue Program RidersVarious6,215 3,986 5,772 3,336 
Pension and Other Postretirement Benefit Plans
Up to 1 year
2,603 — 2,603 — 
Derivative InstrumentsVarious4,179 — 6,214 — 
OtherVarious267 111 395 62 
Total Regulatory Liabilities$27,211 $233,989 $24,844 $234,430 
1Costs subject to recovery without a rate of return.
2Amount eligible for recovery includes an incentive or rate of return.
v3.22.1
Short-Term and Long-Term Borrowings
 3 Months Ended
Mar. 31, 2022
Debt Disclosure [Abstract]  
Short-Term and Long-Term Borrowings Short-Term and Long-Term Borrowings
The following is a summary of our outstanding short- and long-term borrowings by borrower, OTC or Otter Tail Power (OTP), as of March 31, 2022 and December 31, 2021:
Short-Term Debt
The following is a summary of our lines of credit as of March 31, 2022 and December 31, 2021:
March 31, 2022December 31,
2021
(in thousands)Line LimitAmount OutstandingLetters
of Credit		Amount AvailableAmount Available
OTC Credit Agreement$170,000 $43,281 $— $126,719 $147,363 
OTP Credit Agreement170,000 54,489 7,844 107,667 88,315 
Total$340,000 $97,770 $7,844 $234,386 $235,678 
Long-Term Debt
The following is a summary of outstanding long-term debt by borrower as of March 31, 2022 and December 31, 2021: 
(in thousands)
EntityDebt InstrumentRateMaturityMarch 31,
2022		December 31,
2021
OTCGuaranteed Senior Notes3.55%12/15/26$80,000 $80,000 
OTPSeries 2007B Senior Unsecured Notes6.15%08/20/2230,000 30,000 
OTPSeries 2007C Senior Unsecured Notes6.37%08/02/2742,000 42,000 
OTPSeries 2013A Senior Unsecured Notes4.68%02/27/2960,000 60,000 
OTPSeries 2019A Senior Unsecured Notes 3.07%10/10/2910,000 10,000 
OTPSeries 2020A Senior Unsecured Notes3.22%02/25/3010,000 10,000 
OTPSeries 2020B Senior Unsecured Notes3.22%08/20/3040,000 40,000 
OTPSeries 2021A Senior Unsecured Notes2.74%11/29/3140,000 40,000 
OTPSeries 2007D Senior Unsecured Notes6.47%08/20/3750,000 50,000 
OTPSeries 2019B Senior Unsecured Notes3.52%10/10/3926,000 26,000 
OTPSeries 2020C Senior Unsecured Notes3.62%02/25/4010,000 10,000 
OTPSeries 2013B Senior Unsecured Notes5.47%02/27/4490,000 90,000 
OTPSeries 2018A Senior Unsecured Notes4.07%02/07/48100,000 100,000 
OTPSeries 2019C Senior Unsecured Notes3.82%10/10/4964,000 64,000 
OTPSeries 2020D Senior Unsecured Notes3.92%02/25/5015,000 15,000 
OTPSeries 2021B Senior Unsecured Notes3.69%11/29/51100,000 100,000 
Total$767,000 $767,000 
Less:Current Maturities, Net of Unamortized Debt Issuance Costs29,990 29,983 
Unamortized Long-Term Debt Issuance Costs2,936 3,003 
Total Long-Term Debt, Net of Unamortized Debt Issuance Costs$734,074 $734,014 
On June 10, 2021, OTP entered into a Note Purchase Agreement pursuant to which OTP agreed to issue, in a private placement transaction, $230.0 million of senior unsecured notes consisting of (a) $40.0 million of 2.74% Series 2021A Senior Unsecured Notes due November 29, 2031, (b) $100.0 million of 3.69% Series 2021B Senior Unsecured Notes due November 29, 2051 and (c) $90.0 million of 3.77% Series 2022A Senior Unsecured Notes due May 20, 2052. During the year ended December 31, 2021, OTP issued its Series 2021A and Series 2021B notes for aggregate proceeds of $140.0 million, which were used to repay the Series 2011A notes. The issuance of the Series 2022A notes is scheduled to close, subject to the satisfaction of certain customary conditions to closing, in May 2022.
Financial Covenants
Certain of OTC's and OTP's short- and long-term debt agreements require the borrower, whether OTC or OTP, to maintain certain financial covenants, including a maximum debt to total capitalization ratio of 0.60 to 1.00, a minimum interest and dividend coverage ratio of 1.50 to 1.00, and a maximum level of priority indebtedness. As of March 31, 2022, OTC and OTP were in compliance with these financial covenants.
v3.22.1
Pension Plan and Other Postretirement Benefits
 3 Months Ended
Mar. 31, 2022
Retirement Benefits [Abstract]  
Pension Plan and Other Postretirement Benefits Employee Postretirement Benefits
Pension Plan and Other Postretirement Benefits
The Company sponsors a noncontributory funded pension plan (the "Pension Plan"), an unfunded, nonqualified Executive Survivor and Supplemental Retirement Plan, both accounted for as defined benefit pension plans, and a postretirement healthcare plan accounted for as an other postretirement benefit plan.
The following table includes the components of net periodic benefit cost of our defined benefit pension plans and other postretirement benefits for the three months ended March 31, 2022 and 2021:
Pension Benefits (Pension Plan)Pension Benefits (ESSRP)Postretirement Benefits
(in thousands)202220212022202120222021
Service Cost$1,644 $1,866 $49 $47 $335 $430 
Interest Cost3,086 2,915 335 307 510 473 
Expected Return on Assets(5,921)(5,590)— — — — 
Amortization of Prior Service Cost— — — — (1,433)(1,433)
Amortization of Net Actuarial Loss1,966 2,728 142 155 766 943 
Net Periodic Benefit Cost$775 $1,919 $526 $509 $178 $413 
The following table includes the impact of regulation on the recognition of periodic benefit cost arising from pension and other postretirement benefits for the three months ended March 31, 2022 and 2021:
(in thousands)20222021
Net Periodic Benefit Cost$1,479 $2,841 
Net Amount Amortized (Deferred) Due to the Effect of Regulation527 (115)
Net Periodic Benefit Cost Recognized$2,006 $2,726 
We had no minimum funding requirements for our pension plan or any other postretirement benefit plans as of December 31, 2021, but made a discretionary contribution of $20.0 million to our pension plan in February 2022.
v3.22.1
Income Taxes
 3 Months Ended
Mar. 31, 2022
Income Tax Disclosure [Abstract]  
Income Taxes Income TaxesThe reconciliation of the statutory federal income tax rate to our effective tax rate for each of the three months ended March 31, 2022 and 2021 is as follows:
Three Months Ended March 31,
20222021
Federal Statutory Rate21.0 %21.0 %
Increases (Decreases) in Tax from:
State Taxes on Income, Net of Federal Tax5.0 5.0 
Production Tax Credits (PTCs)(4.4)(7.6)
Amortization of Excess Deferred Income Taxes(1.3)(2.9)
Excess Tax Deduction on Stock Awards(0.5)(0.1)
North Dakota Wind Tax Credit Amortization, Net of Federal Tax(0.2)(0.4)
Corporate-Owned Life Insurance0.2 (0.5)
Other, Net(0.1)0.3 
Effective Tax Rate19.7 %14.8 %
v3.22.1
Commitments and Contingencies
 3 Months Ended
Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
Contingencies
FERC ROE. In November 2013 and February 2015, customers filed complaints with Federal Energy Regulatory Commission (FERC) seeking to reduce the return on equity (ROE) component of the transmission rates that Midcontinent Independent System Operator, Inc. (MISO) transmission owners, including OTP, may collect under the MISO tariff rate. FERC's most recent order, issued on November 19, 2020, adopted a revised ROE methodology and set the base ROE at 10.02% (10.52% with an adder) effective for the fifteen-month period from November 2013 to February 2015 and on a prospective basis beginning in September 2016. The order also dismissed any complaints covering the period from February 2015 to May 2016. The November 2020 opinion is subject to judicial review. We have deferred recognition and recorded a refund liability of $2.4 million as of March 31, 2022. This refund liability reflects our best estimate of required refunds to customers once all regulatory and judicial proceedings are completed.
Regional Haze Rule (RHR). The RHR was adopted in an effort to improve visibility in national parks and wilderness areas. The RHR requires states, in coordination with the Environmental Protection Agency (EPA) and other governmental agencies, to develop and implement plans to achieve natural visibility conditions. The second RHR implementation period covers the years 2018-2028. States are required to submit a state implementation plan to assess reasonable progress with the RHR and determine what additional emission reductions are appropriate, if any.
Coyote Station, OTP's jointly owned coal-fired power plant in North Dakota, is subject to assessment in the second implementation period under the North Dakota state implementation plan. In September 2021, the North Dakota Department of Environmental Quality (NDDEQ) made public a draft of its state implementation plan. The plan concluded it is not reasonable to require additional emission controls during this planning period. In January 2022, prior to the submission to the EPA by the NDDEQ, the EPA provided preliminary comments on the draft North Dakota state
implementation plan in which it expressed disagreement with the NDDEQ's recommendation to forgo additional emission controls. Following a consultation and public comment period, and any subsequent modifications to the plan, the NDDEQ will submit its state implementation plan to the EPA for approval.
We cannot predict with certainty the impact the state implementation plan may have on our business until the state implementation plan has been approved or otherwise acted on by the EPA. However, significant emission control investments could be required and the recovery of such costs from customers would require regulatory approval. Alternatively, investments in emission control equipment may prove to be uneconomic and result in the early retirement of or the sale of our interest in Coyote Station, subject to regulatory approval. We cannot estimate the ultimate financial effects such a retirement or sale may have on our consolidated operating results, financial position or cash flows, but such amounts could be material and the recovery of such costs in rates would be subject to regulatory approval.
Other Contingencies. We are party to litigation and regulatory matters arising in the normal course of business. We regularly analyze relevant information and, as necessary, estimate and record accrued liabilities for legal, regulatory enforcement and other matters in which a loss is probable of occurring and can be reasonably estimated. We believe the effect on our consolidated operating results, financial position and cash flows, if any, for the disposition of all matters pending as of March 31, 2022, other than those discussed above, will not be material.
v3.22.1
Stockholders' Equity
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
Stockholders' Equity Stockholders' Equity
Registration Statements
On May 3, 2021, we filed a shelf registration statement with the SEC under which we may offer for sale, from time to time, either separately or together in any combination, equity, debt or other securities described in the shelf registration statement. No new debt or equity has been issued pursuant to the registration statement. The registration statement expires in May 2024.
On May 3, 2021, we filed a second registration statement with the SEC for the issuance of up to 1,500,000 common shares under an Automatic Dividend Reinvestment and a Share Purchase Plan, which provides shareholders, retail customers of OTP and other interested investors methods of purchasing our common shares, by reinvesting their dividends or making optional cash investments. Shares purchased under the plan may be newly issued common shares or common shares purchased on the open market. During the three months ended March 31, 2022, we issued 36,104 shares under this program. We repurchased a sufficient number of shares on the open market to satisfy issuance under the plan; accordingly no proceeds from the issuance were received. As of March 31, 2022, there was 1,348,716 shares available for purchase or issuance under the plan. The registration statement expires in May 2024.
Dividend Restrictions
OTC is a holding company with no significant operations of its own. The primary source of funds for payments of dividends to our shareholders is from dividends paid or distributions made by our subsidiaries. As a result of certain statutory limitations or regulatory or financing agreements, restrictions could occur on the amount of distributions allowed to be made by our subsidiaries. Both the OTC Credit Agreement and OTP Credit Agreement contain restrictions on the payment of cash dividends upon a default or event of default, including failure to maintain certain financial covenants. As of March 31, 2022, we were in compliance with these financial covenants.
Under the Federal Power Act, a public utility may not pay dividends from any funds properly included in a capital account. What constitutes “funds properly included in a capital account” is undefined in the Federal Power Act or the related regulations; however, the FERC has consistently interpreted the provision to allow dividends to be paid as long as i) the source of the dividends is clearly disclosed, ii) the dividend is not excessive and iii) there is no self-dealing on the part of corporate officials.
The Minnesota Public Utilities Commission (MPUC) indirectly limits the amount of dividends OTP can pay to the Company by requiring an equity-to-total-capitalization ratio between 48.0% and 58.7% based on OTP’s most recent capital structure petition effective by order of the MPUC on January 26, 2022. As of March 31, 2022, OTP’s equity-to-total-capitalization ratio including short-term debt was 53.2% and its net assets restricted from distribution totaled approximately $682.0 million. Under the MPUC order relating to the Company's 2021 capital structure petition, total capitalization for OTP cannot exceed $1.7 billion.
v3.22.1
Accumulated Other Comprehensive Income (Loss)
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Income (Loss)The following shows the changes in accumulated other comprehensive loss for the three months ended March 31, 2022 and 2021:
(in thousands)Pension and Other Postretirement BenefitsNet Unrealized Gain (Losses) on Available-for-Sale SecuritiesTotal
Balance, December 31, 2021
$(6,537)$13 $(6,524)
Other Comprehensive Loss Before Reclassifications, net of tax— (231)(231)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)(190)
(1)
— 
(2)
(190)
Total Other Comprehensive Income (Loss)(190)(231)(421)
Balance, March 31, 2022
$(6,727)$(218)$(6,945)
Balance, December 31, 2020
$(8,716)$209 $(8,507)
Other Comprehensive Loss Before Reclassifications, net of tax— (32)(32)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)150 
(1)
(3)
(2)
147 
Total Other Comprehensive Income (Loss)150 (35)115 
Balance, March 31, 2021
$(8,566)$174 $(8,392)
(1) Included in the computation of net periodic pension and other postretirement benefit costs. See Note 7.
(2) Included in other income (expense), net on the accompanying consolidated statements of income.
v3.22.1
Share-Based Payments
 3 Months Ended
Mar. 31, 2022
Share-based Payment Arrangement [Abstract]  
Share-Based Payments Share-Based Payments
Stock Compensation Expense
Stock-based compensation expense arising from our employee stock purchase plan and share-based compensation plans, recognized within operating expenses in the consolidated statements of income, amounted to $4.9 million and $4.2 million for the three months ended March 31, 2022 and 2021, respectively.
Restricted Stock Awards. We grant restricted stock awards to members of our Board of Directors and restricted stock units to certain key employees. The awards vest, depending on award type and recipient, either ratably over periods of three or four years or cliff vest after four years. Vesting is accelerated in certain circumstances, including on retirement.
The following is a summary of stock award activity for the three months ended March 31, 2022:
SharesWeighted Average
Grant-Date
Fair Value
Nonvested, January 1, 2022
138,093 $44.48 
Granted15,842 61.39 
Vested(18,969)46.49 
Forfeited— — 
Nonvested, March 31, 2022
134,966 $46.18 
The fair value of vested awards was $1.2 million and $0.7 million during the three months ended March 31, 2022 and 2021, respectively.
Stock Performance Awards. Stock performance awards are granted to executive officers and certain other key employees. The awards vest at the end of a three year performance period. The number of common shares awarded, if any, at the end of the performance period ranges from zero to 150% of the target amount based on two performance measures: i) total shareholder return relative to a peer group and ii) return on equity. Vesting of the awards is accelerated in certain circumstances, including on retirement. The amount of common shares awarded on an accelerated vesting is based either on actual performance at the end of the performance period or the amount of common shares earned at target.
The grant date fair value of stock performance awards granted during the three months ended March 31, 2022 and 2021 was determined using a Monte Carlo fair value simulation model incorporating the following assumptions:
20222021
Risk-free interest rate1.52 %0.18 %
Expected term (in years)3.003.00
Expected volatility32.00 %32.00 %
Dividend yield2.90 %3.60 %
The risk-free interest rate was derived from yields on U.S. government bonds of a similar term. The expected term of the award is equal to the three-year performance period. Expected volatility was estimated based on actual historical volatility of our common stock. Dividend yield was estimated based on historic and future yield estimates.
The following is a summary of stock performance award activity for the three months ended March 31, 2022 (share amounts reflect awards at target):
 SharesWeighted Average
Grant-Date
Fair Value
Nonvested, January 1, 2022
189,600 $42.54 
Granted55,800 54.91 
Vested(55,600)43.30 
Forfeited— — 
Nonvested, March 31, 2022
189,800 $45.95 
The fair value of vested awards was $5.1 million and $2.5 million during the three months ended March 31, 2022 and 2021, respectively.
v3.22.1
Earnings Per Share
 3 Months Ended
Mar. 31, 2022
Earnings Per Share [Abstract]  
Earnings Per Share Earnings Per Share
The numerator used in the calculation of both basic and diluted earnings per common share is net income. The denominator used in the calculation of basic earnings per common share is the weighted average number of common shares outstanding during the period. The denominator used in the calculation of diluted earnings per common share is derived by adjusting basic shares outstanding for the dilutive effect of potential common shares outstanding, which consist of time and performance based stock awards and employee stock purchase plan shares.
The following includes the computation of the denominator for basic and diluted weighted-average shares outstanding for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31,
(in thousands)20222021
Weighted Average Common Shares Outstanding – Basic41,548 41,455 
Effect of Dilutive Securities:
Stock Performance Awards219 143 
Restricted Stock Awards102 85 
Employee Stock Purchase Plan Shares and Other2 17 
Dilutive Effect of Potential Common Shares323 245 
Weighted Average Common Shares Outstanding – Diluted41,871 41,700 
The amount of shares excluded from diluted weighted-average common shares outstanding because such shares were anti-dilutive was not material for the three months ended March 31, 2022 and 2021.
v3.22.1
Derivative Instruments
 3 Months Ended
Mar. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Derivative Instruments Derivative Instruments
OTP enters into derivative instruments to manage its exposure to future price variability and reduce volatility in prices for our retail customers. These derivative instruments are not designated as qualifying hedging transactions but provide for an economic hedge against future price variability. The instruments are recorded at fair value on the consolidated balance sheets. In accordance with rate-making and cost recovery processes, we recognize a regulatory asset or liability to defer losses or gains from derivative activity until settlement of the associated derivative instrument.
As of March 31, 2022, OTP had outstanding pay-fixed, receive-variable swap agreements with an aggregate notional amount of 156,800 megawatt-hours of electricity, which will be settled periodically throughout 2022 and 2023. As of March 31, 2022, the fair value of these derivative instruments was $4.2 million, which is included in other current assets, and $0.2 million, which is included in other noncurrent liabilities, on the consolidated balance sheets. As of December 31, 2021, the fair value of these types of derivative contracts was $6.2 million, which is included in other current assets. During the three months ended March 31, 2022, contracts matured and were settled in an aggregate amount of $2.8 million.
v3.22.1
Fair Value Measurements
 3 Months Ended
Mar. 31, 2022
Fair Value Disclosures [Abstract]  
Fair Value Measurements Fair Value Measurements
The following tables present our assets and liabilities measured at fair value on a recurring basis as of March 31, 2022 and December 31, 2021 classified by the input method used to measure fair value:
Level 1Level 2Level 3
March 31, 2022
Assets:
Investments:
Money Market Funds$1,893 $— $— 
Mutual Funds6,285 — — 
Corporate Debt Securities— 1,367 — 
Government-Backed and Government-Sponsored Enterprises’ Debt Securities— 7,592 — 
Derivative Instruments— 4,179 — 
Total Assets$8,178 $13,138 $— 
Liabilities:
Derivative Instruments$— $198 $— 
Total Liabilities$— $198 $— 
December 31, 2021
Assets:
Investments:
Money Market Funds$949 $— $— 
Mutual Funds5,432 — — 
Corporate Debt Securities— 1,333 — 
Government-Backed and Government-Sponsored Enterprises’ Debt Securities— 7,869 — 
Derivative Instruments— 6,214 — 
Total Assets$6,381 $15,416 $— 
Level 1 fair value measurements are based on quoted prices (unadjusted) in active markets for identical assets or liabilities that we have the ability to access at the measurement date.
The level 2 fair value measurements for government-backed and government-sponsored enterprises and corporate debt securities are determined on the basis of valuations provided by a third-party pricing service which utilizes industry accepted valuation models and observable market inputs to determine valuation. Some valuations or model inputs used by the pricing service may be based on broker quotes.
The level 2 fair value measurements for derivative instruments are determined by using inputs such as forward electric commodity prices, adjusted for location differences. These inputs are observable in the marketplace throughout the full term of the instrument, can be derived from observable data, or are supported by observable levels at which transactions are executed in the marketplace.
In addition to assets recorded at fair value on a recurring basis, we also hold financial instruments that are not recorded at fair value in the consolidated balance sheets but for which disclosure of the fair value of these financial instruments is provided. The following reflects the carrying value and estimated fair value of these assets and liabilities as of March 31, 2022 and December 31, 2021:
 March 31, 2022December 31, 2021
(in thousands)Carrying
Amount		Fair ValueCarrying
Amount		Fair Value
Assets:
Cash and Cash Equivalents$1,371 $1,371 $1,537 $1,537 
Total1,371 1,371 1,537 1,537 
Liabilities:
Short-Term Debt97,770 97,770 91,163 91,163 
Long-Term Debt764,064 781,531 763,997 878,272 
Total$861,834 $879,301 $855,160 $969,435 
The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value:
Cash Equivalents: The carrying amount approximates fair value because of the short-term maturity of those instruments.
Short-Term Debt: The carrying amount approximates fair value because the debt obligations are short-term and the balances outstanding are subject to variable rates of interest which reset frequently, a Level 2 fair value input.
Long-Term Debt: The fair value of long-term debt is estimated based on current market indications for borrowings of similar maturities, a Level 2 fair value input.
v3.22.1
Summary of Significant Accounting Policies (Policies)
 3 Months Ended
Mar. 31, 2022
Accounting Policies [Abstract]  
Basis of Presentation
Basis of Presentation
The unaudited consolidated financial statements included herein have been prepared pursuant to the rules and regulations of the SEC for interim reporting. Accordingly, they do not include all the information and footnotes required by generally accepted accounting principles. In the opinion of management, we have included all adjustments, including normal recurring accruals, necessary for a fair presentation of the consolidated financial statements for the periods presented. The consolidated financial statements and condensed notes thereto should be read in conjunction with the consolidated financial statements and notes included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2021.
Because of the seasonality of our businesses and other factors, the earnings for the three months ended March 31, 2022 should not be taken as an indication of earnings for all or any part of the balance of the current year or as an indication of earnings for future years.
Use of Estimates
Use of Estimates
We use estimates based on the best information available in recording transactions and balances resulting from business operations. As better information becomes available or actual amounts are known, the recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates.
Reclassifications
Reclassifications
Certain reclassifications of amounts previously reported have been made to the accompanying consolidated statements of shareholders' equity and consolidated statements of cash flows to maintain consistency and comparability between periods presented. The reclassifications had no impact on previously reported shareholders' equity, net cash provided by operating activities, net cash used in investing activities, net cash (used in) provided by financing activities, or cash and cash equivalents.
v3.22.1
Segment Information (Tables)
 3 Months Ended
Mar. 31, 2022
Segment Reporting [Abstract]  
Schedule of Segment Reporting Information, by Segment
Information for each segment and our unallocated corporate costs for the three months ended March 31, 2022 and 2021 are as follows:
Three Months Ended March 31,
(in thousands)20222021
Operating Revenue
Electric$130,416 $123,699 
Manufacturing104,957 75,825 
Plastics139,531 62,186 
Total$374,904 $261,710 
Net Income (Loss)
Electric$19,233 $17,587 
Manufacturing4,084 5,385 
Plastics50,846 9,147 
Corporate(2,160)(1,790)
Total$72,003 $30,329 
The following provides the identifiable assets by segment and corporate assets as of March 31, 2022 and December 31, 2021:
(in thousands)March 31,
2022		December 31,
2021
Identifiable Assets
Electric$2,278,337 $2,283,776 
Manufacturing269,833 251,044 
Plastics184,865 162,565 
Corporate58,706 57,445 
Total$2,791,741 $2,754,830 
v3.22.1
Revenue (Tables)
 3 Months Ended
Mar. 31, 2022
Revenue from Contract with Customer [Abstract]  
Disaggregation of Revenue
We present our operating revenues to external customers, in total and by amounts arising from contracts with customers and alternative revenue program (ARP) arrangements, disaggregated by revenue source and segment for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31,
(in thousands)20222021
Operating Revenues
Electric Segment
Retail: Residential$40,561 $37,485 
Retail: Commercial and Industrial71,171 66,403 
Retail: Other1,907 1,818 
  Total Retail113,639 105,706 
Transmission12,556 11,944 
Wholesale2,463 4,507 
Other1,758 1,542 
Total Electric Segment130,416 123,699 
Manufacturing Segment
Metal Parts and Tooling89,573 62,673 
Plastic Products and Tooling12,445 10,295 
Scrap Metal Sales2,939 2,857 
Total Manufacturing Segment104,957 75,825 
Plastics Segment
PVC Pipe139,531 62,186 
Total Operating Revenue374,904 261,710 
Less: Non-contract Revenues Included Above
Electric Segment - ARP Revenues(2,460)(975)
Total Operating Revenues from Contracts with Customers$377,364 $262,685 
v3.22.1
Select Balance Sheet Information (Tables)
 3 Months Ended
Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Schedule of Receivables
Receivables as of March 31, 2022 and December 31, 2021 are as follows:
(in thousands)March 31,
2022		December 31,
2021
Receivables
Trade$192,315 $142,297 
Other8,139 10,591 
Unbilled Receivables20,229 23,901 
Total Receivables220,683 176,789 
Less: Allowance for Credit Losses(1,787)(1,836)
Receivables, net of allowance for credit losses$218,896 $174,953 
Summary of Activity in Allowance for Credit Losses
The following is a summary of activity in the allowance for credit losses for the three months ended March 31, 2022 and 2021:
March 31,March 31,
(in thousands)20222021
Beginning Balance, January 1$1,836 $3,215 
Additions Charged to Expense210 211 
Reductions for Amounts Written Off, Net of Recoveries(259)(443)
Ending Balance, March 31$1,787 $2,983 
Schedule of Inventories
Inventories consist of the following as of March 31, 2022 and December 31, 2021:
(in thousands)March 31,
2022		December 31,
2021
Finished Goods$37,195 $39,903 
Work in Process33,962 35,705 
Raw Material, Fuel and Supplies74,700 72,882 
Total Inventories$145,857 $148,490 
Schedule of Investments
The following is a summary of our investments as of March 31, 2022 and December 31, 2021:
(in thousands)March 31,
2022		December 31,
2021
Corporate-Owned Life Insurance Policies$40,722 $41,078 
Debt Securities8,959 9,202 
Money Market Funds1,893 949 
Mutual Funds6,285 5,432 
Other Investments34 29 
Total Investments$57,893 $56,690 
Schedule of Property, Plant and Equipment
Major classes of property, plant and equipment as of March 31, 2022 and December 31, 2021 include:
(in thousands)March 31,
2022		December 31,
2021
Electric Plant  
Electric Plant in Service$2,776,778 $2,758,445 
Construction Work in Progress72,347 74,926 
Total Gross Electric Plant2,849,125 2,833,371 
Less Accumulated Depreciation and Amortization829,499 817,302 
Net Electric Plant2,019,626 2,016,069 
Nonelectric Property, Plant and Equipment
Nonelectric Property, Plant and Equipment in Service278,729 273,950 
Construction Work in Progress14,365 16,611 
Total Gross Nonelectric Property, Plant and Equipment293,094 290,561 
Less Accumulated Depreciation and Amortization184,376 182,025 
Net Nonelectric Property, Plant and Equipment108,718 108,536 
Net Property, Plant and Equipment$2,128,344 $2,124,605 
v3.22.1
Regulatory Matters (Tables)
 3 Months Ended
Mar. 31, 2022
Regulatory Assets and Liabilities Disclosure [Abstract]  
Schedule of Regulatory Assets and Liabilities
The following presents our current and long-term regulatory assets and liabilities as of March 31, 2022 and December 31, 2021 and the period we expect to recover or refund such amounts:
Period ofMarch 31, 2022December 31, 2021
(in thousands)Recovery/RefundCurrentLong-TermCurrentLong Term
Regulatory Assets
Pension and Other Postretirement Benefit Plans1
Various$7,791 $113,663 $7,791 $114,961 
Alternative Revenue Program Riders2
Up to 2 years
9,280 5,713 11,889 5,564 
Asset Retirement Obligations1
Asset lives— 1,098 — 742 
ISO Cost Recovery Trackers1
Up to 2 years
220 950 — 1,342 
Unrecovered Project Costs1
Up to 5 years
1,086 1,456 2,136 1,455 
Deferred Rate Case Expenses1
Various542 1,037 607 1,131 
Debt Reacquisition Premiums1
Up to 11 years
68 234 100 240 
Fuel Clause Adjustments1
Up to 1 year
2,767 — 4,819 — 
Other1
Various16 262 — 73 
Total Regulatory Assets$21,770 $124,413 $27,342 $125,508 
Regulatory Liabilities
Deferred Income TaxesAsset lives$— $128,042 $— $129,437 
Plant Removal ObligationsAsset lives8,561 101,850 8,306 101,595 
Fuel Clause Adjustments
Up to 1 year
5,386 — 1,554 — 
Alternative Revenue Program RidersVarious6,215 3,986 5,772 3,336 
Pension and Other Postretirement Benefit Plans
Up to 1 year
2,603 — 2,603 — 
Derivative InstrumentsVarious4,179 — 6,214 — 
OtherVarious267 111 395 62 
Total Regulatory Liabilities$27,211 $233,989 $24,844 $234,430 
1Costs subject to recovery without a rate of return.
2Amount eligible for recovery includes an incentive or rate of return.
v3.22.1
Short-Term and Long-Term Borrowings (Tables)
 3 Months Ended
Mar. 31, 2022
Debt Disclosure [Abstract]  
Schedule of Line of Credit Facilities
The following is a summary of our lines of credit as of March 31, 2022 and December 31, 2021:
March 31, 2022December 31,
2021
(in thousands)Line LimitAmount OutstandingLetters
of Credit		Amount AvailableAmount Available
OTC Credit Agreement$170,000 $43,281 $— $126,719 $147,363 
OTP Credit Agreement170,000 54,489 7,844 107,667 88,315 
Total$340,000 $97,770 $7,844 $234,386 $235,678 
Schedule of Debt
The following is a summary of outstanding long-term debt by borrower as of March 31, 2022 and December 31, 2021: 
(in thousands)
EntityDebt InstrumentRateMaturityMarch 31,
2022		December 31,
2021
OTCGuaranteed Senior Notes3.55%12/15/26$80,000 $80,000 
OTPSeries 2007B Senior Unsecured Notes6.15%08/20/2230,000 30,000 
OTPSeries 2007C Senior Unsecured Notes6.37%08/02/2742,000 42,000 
OTPSeries 2013A Senior Unsecured Notes4.68%02/27/2960,000 60,000 
OTPSeries 2019A Senior Unsecured Notes 3.07%10/10/2910,000 10,000 
OTPSeries 2020A Senior Unsecured Notes3.22%02/25/3010,000 10,000 
OTPSeries 2020B Senior Unsecured Notes3.22%08/20/3040,000 40,000 
OTPSeries 2021A Senior Unsecured Notes2.74%11/29/3140,000 40,000 
OTPSeries 2007D Senior Unsecured Notes6.47%08/20/3750,000 50,000 
OTPSeries 2019B Senior Unsecured Notes3.52%10/10/3926,000 26,000 
OTPSeries 2020C Senior Unsecured Notes3.62%02/25/4010,000 10,000 
OTPSeries 2013B Senior Unsecured Notes5.47%02/27/4490,000 90,000 
OTPSeries 2018A Senior Unsecured Notes4.07%02/07/48100,000 100,000 
OTPSeries 2019C Senior Unsecured Notes3.82%10/10/4964,000 64,000 
OTPSeries 2020D Senior Unsecured Notes3.92%02/25/5015,000 15,000 
OTPSeries 2021B Senior Unsecured Notes3.69%11/29/51100,000 100,000 
Total$767,000 $767,000 
Less:Current Maturities, Net of Unamortized Debt Issuance Costs29,990 29,983 
Unamortized Long-Term Debt Issuance Costs2,936 3,003 
Total Long-Term Debt, Net of Unamortized Debt Issuance Costs$734,074 $734,014 
v3.22.1
Pension Plan and Other Postretirement Benefits (Tables)
 3 Months Ended
Mar. 31, 2022
Retirement Benefits [Abstract]  
Schedule of Net Benefit Costs The following table includes the components of net periodic benefit cost of our defined benefit pension plans and other postretirement benefits for the three months ended March 31, 2022 and 2021:
Pension Benefits (Pension Plan)Pension Benefits (ESSRP)Postretirement Benefits
(in thousands)202220212022202120222021
Service Cost$1,644 $1,866 $49 $47 $335 $430 
Interest Cost3,086 2,915 335 307 510 473 
Expected Return on Assets(5,921)(5,590)— — — — 
Amortization of Prior Service Cost— — — — (1,433)(1,433)
Amortization of Net Actuarial Loss1,966 2,728 142 155 766 943 
Net Periodic Benefit Cost$775 $1,919 $526 $509 $178 $413 
The following table includes the impact of regulation on the recognition of periodic benefit cost arising from pension and other postretirement benefits for the three months ended March 31, 2022 and 2021:
(in thousands)20222021
Net Periodic Benefit Cost$1,479 $2,841 
Net Amount Amortized (Deferred) Due to the Effect of Regulation527 (115)
Net Periodic Benefit Cost Recognized$2,006 $2,726 
v3.22.1
Income Taxes (Tables)
 3 Months Ended
Mar. 31, 2022
Income Tax Disclosure [Abstract]  
Schedule of Effective Income Tax Rate Reconciliation The reconciliation of the statutory federal income tax rate to our effective tax rate for each of the three months ended March 31, 2022 and 2021 is as follows:
Three Months Ended March 31,
20222021
Federal Statutory Rate21.0 %21.0 %
Increases (Decreases) in Tax from:
State Taxes on Income, Net of Federal Tax5.0 5.0 
Production Tax Credits (PTCs)(4.4)(7.6)
Amortization of Excess Deferred Income Taxes(1.3)(2.9)
Excess Tax Deduction on Stock Awards(0.5)(0.1)
North Dakota Wind Tax Credit Amortization, Net of Federal Tax(0.2)(0.4)
Corporate-Owned Life Insurance0.2 (0.5)
Other, Net(0.1)0.3 
Effective Tax Rate19.7 %14.8 %
v3.22.1
Accumulated Other Comprehensive Income (Loss) (Tables)
 3 Months Ended
Mar. 31, 2022
Equity [Abstract]  
Schedule of Changes in Accumulated Other Comprehensive Loss The following shows the changes in accumulated other comprehensive loss for the three months ended March 31, 2022 and 2021:
(in thousands)Pension and Other Postretirement BenefitsNet Unrealized Gain (Losses) on Available-for-Sale SecuritiesTotal
Balance, December 31, 2021
$(6,537)$13 $(6,524)
Other Comprehensive Loss Before Reclassifications, net of tax— (231)(231)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)(190)
(1)
— 
(2)
(190)
Total Other Comprehensive Income (Loss)(190)(231)(421)
Balance, March 31, 2022
$(6,727)$(218)$(6,945)
Balance, December 31, 2020
$(8,716)$209 $(8,507)
Other Comprehensive Loss Before Reclassifications, net of tax— (32)(32)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)150 
(1)
(3)
(2)
147 
Total Other Comprehensive Income (Loss)150 (35)115 
Balance, March 31, 2021
$(8,566)$174 $(8,392)
(1) Included in the computation of net periodic pension and other postretirement benefit costs. See Note 7.
(2) Included in other income (expense), net on the accompanying consolidated statements of income.
v3.22.1
Share-Based Payments (Tables)
 3 Months Ended
Mar. 31, 2022
Share-based Payment Arrangement [Abstract]  
Schedule of Share-based Compensation Arrangements by Share-based Payment Award The following is a summary of stock award activity for the three months ended March 31, 2022:
SharesWeighted Average
Grant-Date
Fair Value
Nonvested, January 1, 2022
138,093 $44.48 
Granted15,842 61.39 
Vested(18,969)46.49 
Forfeited— — 
Nonvested, March 31, 2022
134,966 $46.18 
The grant date fair value of stock performance awards granted during the three months ended March 31, 2022 and 2021 was determined using a Monte Carlo fair value simulation model incorporating the following assumptions:
20222021
Risk-free interest rate1.52 %0.18 %
Expected term (in years)3.003.00
Expected volatility32.00 %32.00 %
Dividend yield2.90 %3.60 %
The following is a summary of stock performance award activity for the three months ended March 31, 2022 (share amounts reflect awards at target):
 SharesWeighted Average
Grant-Date
Fair Value
Nonvested, January 1, 2022
189,600 $42.54 
Granted55,800 54.91 
Vested(55,600)43.30 
Forfeited— — 
Nonvested, March 31, 2022
189,800 $45.95 
v3.22.1
Earnings Per Share (Tables)
 3 Months Ended
Mar. 31, 2022
Earnings Per Share [Abstract]  
Schedule of Earnings Per Share, Basic and Diluted
The following includes the computation of the denominator for basic and diluted weighted-average shares outstanding for the three months ended March 31, 2022 and 2021:
Three Months Ended March 31,
(in thousands)20222021
Weighted Average Common Shares Outstanding – Basic41,548 41,455 
Effect of Dilutive Securities:
Stock Performance Awards219 143 
Restricted Stock Awards102 85 
Employee Stock Purchase Plan Shares and Other2 17 
Dilutive Effect of Potential Common Shares323 245 
Weighted Average Common Shares Outstanding – Diluted41,871 41,700 
v3.22.1
Fair Value Measurements (Tables)
 3 Months Ended
Mar. 31, 2022
Fair Value Disclosures [Abstract]  
Schedule of Fair Value Measurements, Recurring and Nonrecurring The following tables present our assets and liabilities measured at fair value on a recurring basis as of March 31, 2022 and December 31, 2021 classified by the input method used to measure fair value:
Level 1Level 2Level 3
March 31, 2022
Assets:
Investments:
Money Market Funds$1,893 $— $— 
Mutual Funds6,285 — — 
Corporate Debt Securities— 1,367 — 
Government-Backed and Government-Sponsored Enterprises’ Debt Securities— 7,592 — 
Derivative Instruments— 4,179 — 
Total Assets$8,178 $13,138 $— 
Liabilities:
Derivative Instruments$— $198 $— 
Total Liabilities$— $198 $— 
December 31, 2021
Assets:
Investments:
Money Market Funds$949 $— $— 
Mutual Funds5,432 — — 
Corporate Debt Securities— 1,333 — 
Government-Backed and Government-Sponsored Enterprises’ Debt Securities— 7,869 — 
Derivative Instruments— 6,214 — 
Total Assets$6,381 $15,416 $— 
Schedule of Fair Value of Assets and Liabilities The following reflects the carrying value and estimated fair value of these assets and liabilities as of March 31, 2022 and December 31, 2021:
 March 31, 2022December 31, 2021
(in thousands)Carrying
Amount		Fair ValueCarrying
Amount		Fair Value
Assets:
Cash and Cash Equivalents$1,371 $1,371 $1,537 $1,537 
Total1,371 1,371 1,537 1,537 
Liabilities:
Short-Term Debt97,770 97,770 91,163 91,163 
Long-Term Debt764,064 781,531 763,997 878,272 
Total$861,834 $879,301 $855,160 $969,435 
v3.22.1
Summary of Significant Accounting Policies (Details)
 3 Months Ended
Mar. 31, 2022
segment
Accounting Policies [Abstract]  
Number of operating segments 3
v3.22.1
Segment Information - Narrative (Details)
 3 Months Ended
Mar. 31, 2022
segment
Segment Reporting [Abstract]  
Number of reportable segments 3
v3.22.1
Segment Information - Business Segments (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Segment Reporting Information [Line Items]      
Total Operating Revenues $ 374,904 $ 261,710  
Net Income (Loss) 72,003 30,329  
Identifiable Assets 2,791,741   $ 2,754,830
Corporate      
Segment Reporting Information [Line Items]      
Net Income (Loss) (2,160) (1,790)  
Identifiable Assets 58,706   57,445
Electric | Operating Segments      
Segment Reporting Information [Line Items]      
Total Operating Revenues 130,416 123,699  
Net Income (Loss) 19,233 17,587  
Identifiable Assets 2,278,337   2,283,776
Manufacturing | Operating Segments      
Segment Reporting Information [Line Items]      
Total Operating Revenues 104,957 75,825  
Net Income (Loss) 4,084 5,385  
Identifiable Assets 269,833   251,044
Plastics | Operating Segments      
Segment Reporting Information [Line Items]      
Total Operating Revenues 139,531 62,186  
Net Income (Loss) 50,846 $ 9,147  
Identifiable Assets $ 184,865   $ 162,565
v3.22.1
Revenue (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Disaggregation of Revenue [Line Items]    
Total Operating Revenues $ 374,904 $ 261,710
Operating Segments    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues from Contracts with Customers 377,364 262,685
Operating Segments | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 130,416 123,699
Electric Segment - ARP Revenues (2,460) (975)
Operating Segments | Manufacturing    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 104,957 75,825
Operating Segments | Plastics    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 139,531 62,186
Operating Segments | Retail: Residential | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 40,561 37,485
Operating Segments | Retail: Commercial and Industrial | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 71,171 66,403
Operating Segments | Retail: Other | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 1,907 1,818
Operating Segments | Total Retail | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 113,639 105,706
Operating Segments | Transmission | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 12,556 11,944
Operating Segments | Wholesale | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 2,463 4,507
Operating Segments | Other | Electric    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 1,758 1,542
Operating Segments | Metal Parts and Tooling | Manufacturing    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 89,573 62,673
Operating Segments | Plastic Products and Tooling | Manufacturing    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues 12,445 10,295
Operating Segments | Scrap Metal Sales | Manufacturing    
Disaggregation of Revenue [Line Items]    
Total Operating Revenues $ 2,939 $ 2,857
v3.22.1
Select Balance Sheet Information - Schedule of Receivables (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Mar. 31, 2021
Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]        
Trade $ 192,315 $ 142,297    
Other 8,139 10,591    
Unbilled Receivables 20,229 23,901    
Total Receivables 220,683 176,789    
Less: Allowance for Credit Losses (1,787) (1,836) $ (2,983) $ (3,215)
Receivables, net of allowance for credit losses $ 218,896 $ 174,953    
v3.22.1
Select Balance Sheet Information - Summary of Activity in Allowance for Credit Losses (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Accounts Receivable, Allowance for Credit Loss [Roll Forward]    
Beginning Balance, January 1 $ 1,836 $ 3,215
Additions Charged to Expense 210 211
Reductions for Amounts Written Off, Net of Recoveries (259) (443)
Ending Balance, March 31 $ 1,787 $ 2,983
v3.22.1
Select Balance Sheet Information - Schedule of Inventories (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]    
Finished Goods $ 37,195 $ 39,903
Work in Process 33,962 35,705
Raw Material, Fuel and Supplies 74,700 72,882
Inventories $ 145,857 $ 148,490
v3.22.1
Select Balance Sheet Information - Schedule of Investments (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]    
Corporate-Owned Life Insurance Policies $ 40,722 $ 41,078
Debt Securities 8,959 9,202
Money Market Funds 1,893 949
Mutual Funds 6,285 5,432
Other Investments 34 29
Total Investments $ 57,893 $ 56,690
v3.22.1
Select Balance Sheet Information - Schedule of Property, Plant and Equipment (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, net of accumulated depreciation $ 2,128,344 $ 2,124,605
Electric Plant    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 2,849,125 2,833,371
Less Accumulated Depreciation and Amortization 829,499 817,302
Property, Plant and Equipment, net of accumulated depreciation 2,019,626 2,016,069
Nonelectric Property, Plant and Equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 293,094 290,561
Less Accumulated Depreciation and Amortization 184,376 182,025
Property, Plant and Equipment, net of accumulated depreciation 108,718 108,536
Electric Plant in Service | Electric Plant    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 2,776,778 2,758,445
Construction Work in Progress | Electric Plant    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 72,347 74,926
Construction Work in Progress | Nonelectric Property, Plant and Equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 14,365 16,611
Nonelectric Property, Plant and Equipment in Service | Nonelectric Property, Plant and Equipment    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross $ 278,729 $ 273,950
v3.22.1
Regulatory Matters - Regulatory Assets and Liabilities (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current $ 21,770 $ 27,342
Regulatory assets, long-term 124,413 125,508
Regulatory liabilities, current 27,211 24,844
Regulatory liabilities, long -term 233,989 234,430
Deferred Income Taxes    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory liabilities, current 0 0
Regulatory liabilities, long -term 128,042 129,437
Plant Removal Obligations    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory liabilities, current 8,561 8,306
Regulatory liabilities, long -term 101,850 101,595
Fuel Clause Adjustments    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory liabilities, current 5,386 1,554
Regulatory liabilities, long -term $ 0 0
Regulatory Liabilities - Remaining Recovery/Refund Period 1 year  
Alternative Revenue Program Riders    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory liabilities, current $ 6,215 5,772
Regulatory liabilities, long -term 3,986 3,336
Pension and Other Postretirement Benefit Plans    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory liabilities, current 2,603 2,603
Regulatory liabilities, long -term $ 0 0
Regulatory Liabilities - Remaining Recovery/Refund Period 1 year  
Derivative Instruments    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory liabilities, current $ 4,179 6,214
Regulatory liabilities, long -term 0 0
Other    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory liabilities, current 267 395
Regulatory liabilities, long -term 111 62
Pension and Other Postretirement Benefit Plans    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current 7,791 7,791
Regulatory assets, long-term 113,663 114,961
Alternative Revenue Program Riders    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current 9,280 11,889
Regulatory assets, long-term $ 5,713 5,564
Regulatory Assets - Remaining Recovery/Refund Period 2 years  
Asset Retirement Obligations    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current $ 0 0
Regulatory assets, long-term 1,098 742
ISO Cost Recovery Trackers    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current 220 0
Regulatory assets, long-term $ 950 1,342
Regulatory Assets - Remaining Recovery/Refund Period 2 years  
Unrecovered Project Costs    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current $ 1,086 2,136
Regulatory assets, long-term $ 1,456 1,455
Regulatory Assets - Remaining Recovery/Refund Period 5 years  
Deferred Rate Case Expenses    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current $ 542 607
Regulatory assets, long-term 1,037 1,131
Debt Reacquisition Premiums    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current 68 100
Regulatory assets, long-term $ 234 240
Regulatory Assets - Remaining Recovery/Refund Period 11 years  
Fuel Clause Adjustments    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current $ 2,767 4,819
Regulatory assets, long-term 0 0
Other    
Schedule of Regulatory Assets and Liabilities [Line Items]    
Regulatory assets - current 16 0
Regulatory assets, long-term $ 262 $ 73
v3.22.1
Short-Term and Long-Term Borrowings - Lines of Credit (Details) - USD ($)
Mar. 31, 2022
Dec. 31, 2021
Line of Credit Facility [Line Items]    
Line Limit $ 340,000,000  
Amount Outstanding 97,770,000 $ 91,163,000
Letters of Credit 7,844,000  
Amount Available 234,386,000 235,678,000
OTC Credit Agreement    
Line of Credit Facility [Line Items]    
Line Limit 170,000,000  
Amount Outstanding 43,281,000  
Letters of Credit 0  
Amount Available 126,719,000 147,363,000
OTP Credit Agreement    
Line of Credit Facility [Line Items]    
Line Limit 170,000,000  
Amount Outstanding 54,489,000  
Letters of Credit 7,844,000  
Amount Available $ 107,667,000 $ 88,315,000
v3.22.1
Short-Term and Long-Term Borrowings - Breakdown of Outstanding Long-term Debt (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Debt Instrument [Line Items]    
Long-term debt $ 767,000 $ 767,000
Current Maturities, Net of Unamortized Debt Issuance Costs 29,990 29,983
Unamortized Long-Term Debt Issuance Costs 2,936 3,003
Total Long-Term Debt, Net of Unamortized Debt Issuance Costs $ 734,074 734,014
Guaranteed Senior Notes    
Debt Instrument [Line Items]    
Rate 3.55%  
Long-term debt $ 80,000 80,000
Series 2007B Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 6.15%  
Long-term debt $ 30,000 30,000
Series 2007C Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 6.37%  
Long-term debt $ 42,000 42,000
Series 2013A Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 4.68%  
Long-term debt $ 60,000 60,000
Series 2019A Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.07%  
Long-term debt $ 10,000 10,000
Series 2020A Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.22%  
Long-term debt $ 10,000 10,000
Series 2020B Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.22%  
Long-term debt $ 40,000 40,000
Series 2021A Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 2.74%  
Long-term debt $ 40,000 40,000
Series 2007D Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 6.47%  
Long-term debt $ 50,000 50,000
Series 2019B Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.52%  
Long-term debt $ 26,000 26,000
Series 2020C Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.62%  
Long-term debt $ 10,000 10,000
Series 2013B Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 5.47%  
Long-term debt $ 90,000 90,000
Series 2018A Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 4.07%  
Long-term debt $ 100,000 100,000
Series 2019C Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.82%  
Long-term debt $ 64,000 64,000
Series 2020D Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.92%  
Long-term debt $ 15,000 15,000
Series 2021B Senior Unsecured Notes    
Debt Instrument [Line Items]    
Rate 3.69%  
Long-term debt $ 100,000 $ 100,000
v3.22.1
Short-Term and Long-Term Borrowings - Narrative (Details) - USD ($)
 12 Months Ended
Dec. 31, 2021
Mar. 31, 2022
Jun. 10, 2021
Senior Notes      
Debt Instrument [Line Items]      
Aggregate principal amount     $ 230,000,000
Proceeds from issuance of debt $ 140,000,000    
Series 2021A Senior Unsecured Notes      
Debt Instrument [Line Items]      
Interest rate (as a percent)   2.74%  
Series 2021A Senior Unsecured Notes | Senior Notes      
Debt Instrument [Line Items]      
Aggregate principal amount     $ 40,000,000
Interest rate (as a percent)     2.74%
Series 2021B Senior Unsecured Notes      
Debt Instrument [Line Items]      
Interest rate (as a percent)   3.69%  
Series 2021B Senior Unsecured Notes | Senior Notes      
Debt Instrument [Line Items]      
Aggregate principal amount     $ 100,000,000
Interest rate (as a percent)     3.69%
Senior Unsecured Notes 3.77%, Series A, Due May 20, 2052 | Senior Notes      
Debt Instrument [Line Items]      
Aggregate principal amount     $ 90,000,000
Interest rate (as a percent)     3.77%
Minimum      
Debt Instrument [Line Items]      
Interest and dividend coverage ratio   1.50  
Maximum      
Debt Instrument [Line Items]      
Debt to total capitalization ratio   60.00%  
v3.22.1
Pension Plan and Other Postretirement Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Defined Benefit Plan Disclosure [Line Items]    
Net Periodic Benefit Cost $ 1,479 $ 2,841
Pension Plan    
Defined Benefit Plan Disclosure [Line Items]    
Service Cost 1,644 1,866
Interest Cost 3,086 2,915
Expected Return on Assets (5,921) (5,590)
Amortization of Prior Service Cost 0 0
Amortization of Net Actuarial Loss 1,966 2,728
Net Periodic Benefit Cost 775 1,919
Executive Survivor and Supplemental Retirement Plan    
Defined Benefit Plan Disclosure [Line Items]    
Service Cost 49 47
Interest Cost 335 307
Expected Return on Assets 0 0
Amortization of Prior Service Cost 0 0
Amortization of Net Actuarial Loss 142 155
Net Periodic Benefit Cost 526 509
Other Postretirement Benefits Plan    
Defined Benefit Plan Disclosure [Line Items]    
Service Cost 335 430
Interest Cost 510 473
Expected Return on Assets 0 0
Amortization of Prior Service Cost (1,433) (1,433)
Amortization of Net Actuarial Loss 766 943
Net Periodic Benefit Cost $ 178 $ 413
v3.22.1
Pension Plan and Other Postretirement Benefits - Composition of Periodic Benefit Cost (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Retirement Benefits [Abstract]    
Net Periodic Benefit Cost $ 1,479 $ 2,841
Net Amount Amortized (Deferred) Due to the Effect of Regulation 527 (115)
Net Periodic Benefit Cost Recognized $ 2,006 $ 2,726
v3.22.1
Pension Plan and Other Postretirement Benefits - Narrative (Details)
$ in Millions
 1 Months Ended
Feb. 28, 2022
USD ($)
Pension Plan  
Defined Benefit Plan Disclosure [Line Items]  
Contributions by employer $ 20.0
v3.22.1
Income Taxes - Effective Income Tax Rate (Details)
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Income Tax Disclosure [Abstract]    
Federal Statutory Rate 21.00% 21.00%
Increases (Decreases) in Tax from:    
State Taxes on Income, Net of Federal Tax 5.00% 5.00%
Production Tax Credits (PTCs) (4.40%) (7.60%)
Amortization of Excess Deferred Income Taxes (1.30%) (2.90%)
Excess Tax Deduction on Stock Awards (0.50%) (0.10%)
North Dakota Wind Tax Credit Amortization, Net of Federal Tax (0.20%) (0.40%)
Corporate-Owned Life Insurance 0.20% (0.50%)
Other, Net (0.10%) 0.30%
Effective Tax Rate 19.70% 14.80%
v3.22.1
Commitments and Contingencies (Details)
$ in Millions
Mar. 31, 2022
USD ($)
Otter Tail Power Company | Federal Energy Regulatory Commission  
Other Commitments [Line Items]  
Estimated liability of refund obligation $ 2.4
v3.22.1
Stockholders' Equity (Details) - USD ($)
$ in Thousands
 3 Months Ended
Jan. 26, 2022
May 03, 2021
Mar. 31, 2022
Dec. 31, 2021
Class of Stock [Line Items]        
Total capitalization     $ 1,781,212 $ 1,724,791
Otter Tail Power Company        
Class of Stock [Line Items]        
Equity to total capitalization ratio     53.20%  
Net assets restricted from distribution     $ 682,000  
Minimum | Otter Tail Power Company | Minnesota Public Utilities Commission        
Class of Stock [Line Items]        
Public utilities, requested equity capital structure, percentage 48.00%      
Maximum | Otter Tail Power Company        
Class of Stock [Line Items]        
Total capitalization     $ 1,700,000  
Maximum | Otter Tail Power Company | Minnesota Public Utilities Commission        
Class of Stock [Line Items]        
Public utilities, requested equity capital structure, percentage 58.70%      
Second Shelf Registration        
Class of Stock [Line Items]        
Shelf registration (in shares)   1,500,000    
Number of shares issued (in shares)     36,104  
Number of shares available for grant (in shares)     1,348,716  
v3.22.1
Accumulated Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance $ 990,777 $ 870,966
Total Other Comprehensive (Loss) Income (421) 115
Ending balance 1,047,138 887,867
Pension and Other Postretirement Benefits    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance (6,537) (8,716)
Other Comprehensive Loss Before Reclassifications, net of tax 0 0
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (190) 150
Total Other Comprehensive (Loss) Income (190) 150
Ending balance (6,727) (8,566)
Net Unrealized Gain (Losses) on Available-for-Sale Securities    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance 13 209
Other Comprehensive Loss Before Reclassifications, net of tax (231) (32)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) 0 (3)
Total Other Comprehensive (Loss) Income (231) (35)
Ending balance (218) 174
Accumulated Other Comprehensive Income (Loss)    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance (6,524) (8,507)
Other Comprehensive Loss Before Reclassifications, net of tax (231) (32)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (190) 147
Total Other Comprehensive (Loss) Income (421) 115
Ending balance $ (6,945) $ (8,392)
v3.22.1
Share-Based Payments - Narrative (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based payment arrangement, expense $ 4.9 $ 4.2
Restricted Stock Awards    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Awards vesting period 4 years  
Fair value of awards vested $ 1.2 0.7
Restricted Stock Awards | Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Award vesting period 3 years  
Restricted Stock Awards | Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Award vesting period 4 years  
Stock Performance Awards    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Award vesting period 3 years  
Fair value of awards vested $ 5.1 $ 2.5
Stock Performance Awards | Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Percentage of target amount as actual payment 0.00%  
Stock Performance Awards | Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Percentage of target amount as actual payment 150.00%  
v3.22.1
Share-Based Payments - Summary of Restricted Stock Awards and Stock Performance Awards (Details)
 3 Months Ended
Mar. 31, 2022
$ / shares
shares
Restricted Stock Awards  
Shares  
Beginning of year (in shares) | shares 138,093
Granted (in shares) | shares 15,842
Vested (in shares) | shares (18,969)
Forfeited (in shares) | shares 0
End of year (in shares) | shares 134,966
Weighted Average Grant-Date Fair Value  
Beginning of year (in dollars per share) | $ / shares $ 44.48
Granted (in dollars per share) | $ / shares 61.39
Vested (in dollars per share) | $ / shares 46.49
Forfeited (in dollars per share) | $ / shares 0
End of year (in dollars per share) | $ / shares $ 46.18
Stock Performance Awards  
Shares  
Beginning of year (in shares) | shares 189,600
Granted (in shares) | shares 55,800
Vested (in shares) | shares (55,600)
Forfeited (in shares) | shares 0
End of year (in shares) | shares 189,800
Weighted Average Grant-Date Fair Value  
Beginning of year (in dollars per share) | $ / shares $ 42.54
Granted (in dollars per share) | $ / shares 54.91
Vested (in dollars per share) | $ / shares 43.30
Forfeited (in dollars per share) | $ / shares 0
End of year (in dollars per share) | $ / shares $ 45.95
v3.22.1
Share-Based Payments - Weighted-Average Assumptions (Details) - Stock Performance Awards
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rate 1.52% 0.18%
Expected term (in years) 3 years 3 years
Expected volatility 32.00% 32.00%
Dividend yield 2.90% 3.60%
v3.22.1
Earnings Per Share (Details) - shares
shares in Thousands
 3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]    
Weighted Average Common Shares Outstanding - Basic (in shares) 41,548 41,455
Effect of Dilutive Securities:    
Total Dilutive Shares (in shares) 323 245
Weighted Average Common Shares Outstanding – Diluted (in shares) 41,871 41,700
Stock Performance Awards    
Effect of Dilutive Securities:    
Effect of Dilutive Securities (in shares) 219 143
Restricted Stock Awards    
Effect of Dilutive Securities:    
Effect of Dilutive Securities (in shares) 102 85
Employee Stock Purchase Plan Shares and Other    
Effect of Dilutive Securities:    
Effect of Dilutive Securities (in shares) 2 17
v3.22.1
Derivative Instruments (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2022
USD ($)
MWh
Mar. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Other Current Assets      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Fair value of outstanding swap agreements $ 4.2 $ 4.2 $ 6.2
Other Noncurrent Liabilities      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Fair value of outstanding swap agreements $ 0.2 0.2  
Swap      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Notional amount of outstanding swap agreements | MWh 156,800    
Settlement of derivative contract   $ 2.8  
v3.22.1
Fair Value Measurements - Schedule of Fair Value Measurements, Recurring and Nonrecurring (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Investments:    
Debt Securities $ 8,959 $ 9,202
Level 1 | Fair Value, Recurring    
Investments:    
Money Market Funds 1,893 949
Mutual Funds 6,285 5,432
Total Assets 8,178 6,381
Level 2 | Fair Value, Recurring    
Investments:    
Derivative Instruments 4,179 6,214
Total Assets 13,138 15,416
Liabilities:    
Derivative Instruments 198  
Total 198  
Level 2 | Fair Value, Recurring | Corporate Debt Securities    
Investments:    
Debt Securities 1,367 1,333
Level 2 | Fair Value, Recurring | Government-Backed and Government-Sponsored Enterprises’ Debt Securities    
Investments:    
Debt Securities $ 7,592 $ 7,869
v3.22.1
Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Carrying Amount    
Assets:    
Cash and Cash Equivalents $ 1,371 $ 1,537
Total Assets 1,371 1,537
Liabilities:    
Short-Term Debt 97,770 91,163
Long-Term Debt 764,064 763,997
Total 861,834 855,160
Fair Value    
Assets:    
Cash and Cash Equivalents 1,371 1,537
Total Assets 1,371 1,537
Liabilities:    
Short-Term Debt 97,770 91,163
Long-Term Debt 781,531 878,272
Total $ 879,301 $ 969,435
v3.22.1
Label Element Value
Capital Expenditures Incurred but Not yet Paid us-gaap_CapitalExpendituresIncurredButNotYetPaid $ 9,165,000
Capital Expenditures Incurred but Not yet Paid us-gaap_CapitalExpendituresIncurredButNotYetPaid $ 18,962,000