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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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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Amount, after accumulated amortization, of debt discount (premium).

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The effective interest rate at the end of the reporting period.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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No definition available.

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Debt (Components of Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Feb. 26, 2023	Dec. 31, 2022	May 31, 2022	Mar. 31, 2022	Jan. 06, 2022	Apr. 07, 2020	Jul. 31, 2018	Jan. 31, 2015
Debt Instrument [Line Items]
Total debt	$ 3,953		$ 4,414
Unamortized Issuance Expense	(39)		(44)
Unamortized Debt Premium/Discount	21		22
Total long-term debt	3,935		4,392
Total debt	3,935		4,392
Long-term debt
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	3,953		4,414
Unamortized Issuance Expense	(39)		(44)
Unamortized Debt Premium/Discount	21		22
Total long-term debt	3,935		4,392
Senior Notes \| 4.95% Senior Notes due January 2025
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	389		389
Unamortized Issuance Expense	(1)		(1)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 388		$ 388
Stated interest rate	4.95%		4.95%	5.70%		5.95%	6.45%	6.20%	4.95%
Senior Notes \| 7.75% Senior Notes due October 2027
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross			$ 421
Unamortized Issuance Expense			(3)
Unamortized Debt Premium/Discount			0
Total long-term debt			$ 418
Stated interest rate		7.75%	7.75%		7.75%
Senior Notes \| 8.375% Senior Notes due September 2028
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 304		$ 304
Unamortized Issuance Expense	(3)		(3)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 301		$ 301
Stated interest rate	8.375%		8.375%		8.375%
Senior Notes \| 5.375% Senior Notes due February 2029
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 700		$ 700
Unamortized Issuance Expense	(5)		(5)
Unamortized Debt Premium/Discount	21		22
Total long-term debt	$ 716		$ 717
Stated interest rate	5.375%		5.375%
Senior Notes \| 5.375% Senior Notes due March 2030
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 1,200		$ 1,200
Unamortized Issuance Expense	(15)		(16)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 1,185		$ 1,184
Stated interest rate	5.375%		5.375%
Senior Notes \| 4.75% Senior Notes due February 2032
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 1,150		$ 1,150
Unamortized Issuance Expense	(15)		(16)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 1,135		$ 1,134
Stated interest rate	4.75%		4.75%
Line of Credit \| 2022 Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, variable interest rate	6.69%		6.15%
Line of Credit \| 2022 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 210		$ 250
Unamortized Issuance Expense	0		0
Unamortized Debt Premium/Discount	0		0
Total long-term debt	210		250
Other long-term assets \| Line of Credit \| 2022 Revolving Credit Facility
Debt Instrument [Line Items]
Unamortized Issuance Expense	$ (18)		$ (19)