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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Long-Term Debt (8.73% 2022 RS Cogen) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Jul. 31, 2000
Debt Disclosure [Abstract]
Long-term Debt	$ 5,180	$ 3,566
8.73% 2022 RS Cogen Debt \| Senior Notes
Debt Disclosure [Abstract]
Stated interest rate (percent)	8.73%
Long-term Debt	$ 19	$ 0
RS Cogen
Credit Agreement [Line Items]
Ownership percentage by parent	50.00%
RS Cogen \| 8.73% 2022 RS Cogen Debt \| Senior Secured Revolving Credit Facility [Member]
Credit Agreement [Line Items]
Ownership percentage by parent	50.00%
Line of Credit Facility, Maximum Borrowing Capacity			$ 75