Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Ratepayer Net Refund

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Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income taxes
Income tax deductions	$ 164.0	$ 70.0	$ 102.0
TCJA refund	105.0			$ 108.0
Unrecognized tax benefits that would impact effective tax rate	3.7
State
Income taxes
Net operating loss resulting from repairs and maintenance deductions	181.3
State tax credits	4.2
Estimated carried-forward portion of tax credits	2.2
Federal
Income taxes
Net operating loss resulting from repairs and maintenance deductions	$ 140.8