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Income Taxes (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Income tax benefit (expense) | $ (494) | $ (16,002)
Effective Tax Rate | 0.50% | 14.10%
Effective Income Tax Reconciliation, Tax Benefit From Amortization Of Excess Deferred Income Taxes | $ 1,500 |
Wind Assets |  |
Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Amount | 1,300 |
Colorado Electric |  |
Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of 2017 Amount, Tax Benefit from Bill Credit | $ 7,600 |

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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