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v3.22.1

Other Comprehensive Income: Reclassification Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2022 | Mar. 31, 2021
Condensed Statement of Income Captions [Line Items] |  |
Interest Expense | $ 38,821 | $ 37,825
Fuel, purchased power and cost of natural gas sold | 436,926 | 293,147
Operations and maintenance | 136,132 | 129,679
Income tax benefit (expense) | (14,488) | (494)
Net income (loss) | 121,024 | 100,487
Reclassification out of Accumulated Other Comprehensive Income |  |
Condensed Statement of Income Captions [Line Items] |  |
Net income (loss) | 1,041 | (911)
Cash Flow Hedging | Reclassification out of Accumulated Other Comprehensive Income |  |
Condensed Statement of Income Captions [Line Items] |  |
Income before Income Taxes | 1,541 | (744)
Income tax benefit (expense) | (375) | 198
Net income (loss) | 1,166 | (546)
Cash Flow Hedging | Reclassification out of Accumulated Other Comprehensive Income | Interest rate swaps |  |
Condensed Statement of Income Captions [Line Items] |  |
Interest Expense | (713) | (713)
Cash Flow Hedging | Reclassification out of Accumulated Other Comprehensive Income | Commodity Contract |  |
Condensed Statement of Income Captions [Line Items] |  |
Fuel, purchased power and cost of natural gas sold | 2,254 | (31)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Cost | Reclassification out of Accumulated Other Comprehensive Income |  |
Condensed Statement of Income Captions [Line Items] |  |
Operations and maintenance | 24 | 25
Accumulated Defined Benefit Plans Adjustment, Net Unamortized Gain (Loss) | Reclassification out of Accumulated Other Comprehensive Income |  |
Condensed Statement of Income Captions [Line Items] |  |
Operations and maintenance | (188) | (598)
Accumulated Defined Benefit Plans Adjustment | Reclassification out of Accumulated Other Comprehensive Income |  |
Condensed Statement of Income Captions [Line Items] |  |
Income before Income Taxes | (164) | (573)
Income tax benefit (expense) | 39 | 208
Net income (loss) | $ (125) | $ (365)

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