Long-Term Debt, Excluding Maturities, Gross

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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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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Debt (Components of Debt) (Details) - USD ($) $ in Thousands	1 Months Ended
	Mar. 31, 2022	Jan. 06, 2022	Dec. 31, 2021	Dec. 22, 2021	Nov. 30, 2021	Sep. 01, 2021	Aug. 30, 2021	Aug. 31, 2020	Apr. 07, 2020	Jul. 31, 2018	Jan. 31, 2015
Debt Instrument [Line Items]
Current portion of long-term debt	$ 5,000		$ 206,000
Debt instrument, excluding current maturities, gross			5,234,000
Total debt	4,932,000		5,440,000
Unamortized Issuance Expense	(55,000)		(57,000)
Unamortized Debt Premium/Discount	23,000		24,000
Total long-term debt	4,895,000		5,201,000
Total debt	4,900,000		5,407,000
Long-term debt
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	4,927,000
Unamortized Issuance Expense	(55,000)
Unamortized Debt Premium/Discount	23,000
Total long-term debt	4,895,000
Senior Notes
Debt Instrument [Line Items]
Current portion of long-term debt	5,000
Unamortized Issuance Expense	0
Unamortized Debt Premium/Discount	$ 0
Senior Notes \| 4.10% Senior Notes due March 2022
Debt Instrument [Line Items]
Current portion of long-term debt			$ 201,000
Stated interest rate	4.10%		4.10%				4.10%
Senior Notes \| Term Loan Due June 2027
Debt Instrument [Line Items]
Credit facility, variable interest rate			3.00%
Stated interest rate	3.30%		3.00%
Senior Notes \| 4.95% Senior Notes due January 2025 (3)
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 389,000		$ 389,000
Unamortized Issuance Expense	(1,000)		(1,000)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 388,000		$ 388,000
Stated interest rate	4.95%	5.95%	4.95%				4.95%		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	$ 425,000		$ 440,000
Unamortized Issuance Expense	(4,000)		(4,000)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 421,000		$ 436,000
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	$ 345,000		$ 350,000
Unamortized Issuance Expense	(5,000)		(5,000)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 340,000		$ 345,000
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	$ 700,000
Unamortized Issuance Expense	(6,000)
Unamortized Debt Premium/Discount	24,000
Total long-term debt	$ 718,000
Total debt					$ 700,000	$ 700,000
Stated interest rate	5.375%				5.375%	5.375%
Senior Notes \| 5.375% Senior Notes due September 2029
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross			$ 700,000
Unamortized Issuance Expense			(6,000)
Unamortized Debt Premium/Discount			25,000
Total long-term debt			$ 719,000
Stated interest rate			5.375%
Senior Notes \| 5.375% Senior Notes due September 2030
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 1,200,000
Unamortized Issuance Expense	(16,000)
Unamortized Debt Premium/Discount	0
Total long-term debt	$ 1,184,000
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			$ 1,200,000
Unamortized Issuance Expense			(17,000)
Unamortized Debt Premium/Discount			0
Total long-term debt			$ 1,183,000
Stated interest rate			5.375%
Senior Notes \| 4.75% Senior Notes due February 2032
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 1,150,000		$ 1,150,000
Unamortized Issuance Expense	(16,000)		(17,000)
Unamortized Debt Premium/Discount	0		0
Total long-term debt	$ 1,134,000		$ 1,133,000
Stated interest rate	4.75%		4.75%	4.75%
Line of Credit \| 2018 Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, variable interest rate	2.10%		2.08%
Line of Credit \| 2018 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, excluding current maturities, gross	$ 174,000		$ 460,000
Unamortized Issuance Expense	0		0
Unamortized Debt Premium/Discount	0		0
Total long-term debt	174,000		460,000
Term Loan \| Term Loan Due June 2027
Debt Instrument [Line Items]
Current portion of long-term debt	5,000		5,000
Debt instrument, excluding current maturities, gross	544,000		545,000
Unamortized Issuance Expense	(7,000)		(7,000)
Unamortized Debt Premium/Discount	(1,000)		(1,000)
Total long-term debt	$ 536,000		537,000
Credit facility, variable interest rate	3.30%
Repayments of secured debt	$ 1,375
Other long-term assets \| Line of Credit \| 2018 Revolving Credit Facility
Debt Instrument [Line Items]
Unamortized Issuance Expense	$ (9,000)		$ (10,000)