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Pre-tax gains (losses) reclassified into income during the period from regulatory assets and (liabilities)

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No definition available.

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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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No definition available.

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Nominal number of units used to calculate payment on derivative.

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Net fair value of all derivative instruments designated as fair value hedging instruments.

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Fair Value of Financial Assets and Liabilities - Impact of Derivative Activities on Income (Details) MMBTU in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($) MMBTU	Mar. 31, 2021 USD ($)	Dec. 31, 2021 MMBTU
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments designated as fair value hedges	$ 0	$ 0
Financial Impact of Qualifying Fair Value Hedges on Earnings [Abstract]
Derivative instruments designated as fair value hedges	$ 0	0
Natural Gas Commodity [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount \| MMBTU	0		0
Other Derivative Instruments \| Natural Gas Commodity
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax (gains) losses reclassified into income during the period from regulatory assets and (liabilities)	$ (1)	$ (1)