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

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Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. 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	Dec. 31, 2023	Feb. 26, 2023	Dec. 31, 2022	Dec. 30, 2022	May 31, 2022	Jan. 06, 2022	Nov. 30, 2021	Sep. 01, 2021	Aug. 30, 2021	Apr. 07, 2020	Jul. 31, 2018	Jan. 31, 2015
Debt Instrument [Line Items]
Total	$ 3,963		$ 4,414
Unamortized Issuance Expense	(34)		(44)
Unamortized Debt Premium / Discount	18		22
Long-term debt	3,947		4,392
Total	3,947		4,392
Debt issuance costs, line of credit	$ 15		$ 19
Line of Credit \| 2022 Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, variable interest rate	7.20%		6.15%
Line of Credit \| 2022 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 220		$ 250	$ 250
Unamortized Issuance Expense	0		0
Unamortized Debt Premium / Discount	0		0
Long-term debt	220		250
Senior Notes \| 4.95% Senior Notes due January 2025
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	389		389
Unamortized Issuance Expense	0		(1)
Unamortized Debt Premium / Discount	0		0
Long-term debt	$ 389		$ 388
Stated interest rate	4.95%		4.95%			5.95%			4.95%	6.45%	6.20%	4.95%
Senior Notes \| 4.95% Senior Notes due January 2025 \| Minimum
Debt Instrument [Line Items]
Stated interest rate					5.95%
Senior Notes \| 4.95% Senior Notes due January 2025 \| Maximum
Debt Instrument [Line Items]
Stated interest rate					5.70%
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
Long-term debt			$ 418
Stated interest rate		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
Long-term debt	$ 301		$ 301
Stated interest rate	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	18		22
Long-term debt	$ 713		$ 717
Total							$ 700	$ 700
Stated interest rate	5.375%		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	(13)		(16)
Unamortized Debt Premium / Discount	0		0
Long-term debt	$ 1,187		$ 1,184
Stated interest rate	5.375%		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	(13)		(16)
Unamortized Debt Premium / Discount	0		0
Long-term debt	$ 1,137		$ 1,134
Stated interest rate	4.75%		4.75%