Additions to other financing obligations

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- Definition

Percent Of Construction Costs Capitalized

+ References

No definition available.

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- Definition

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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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

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

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

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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- References

No definition available.

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- Definition

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.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of long-term debt classified as other, payable within one year or the operating cycle, if longer.

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Amount of long-term debt classified as other, payable after one year or the operating cycle, if longer.

+ References

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- Definition

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.

+ References

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Debt and Financing Arrangements Debt Disclosure (Details) - USD ($)			1 Months Ended
	Oct. 01, 2018	Jun. 15, 2018	Sep. 30, 2017	Dec. 31, 2019	Nov. 01, 2019	Dec. 31, 2018	Mar. 15, 2018
Debt Instrument [Line Items]
Total long-term debt, including current portion				$ 4,098,480,000		$ 4,049,786,000
Other financing obligation				1,115,980,000		1,067,286,000
Unamortized debt issuance costs				(22,876,000)		(24,242,000)
Unamortized debt premium and discount, net				(10,634,000)		(11,137,000)
Long-term debt due within one year				20,180,000		15,419,000
Total long-term debt				4,044,790,000		3,998,988,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2020				20,180,000
2021				22,102,000
2022				24,207,000
2023				26,511,000
2024				29,036,000
4.0% due 2028 [Member]
Debt Instrument [Line Items]
Long-term debt face amount							$ 400,000,000
Long-term debt interest rate							4.00%
4.6 % due 2048 [Member]
Debt Instrument [Line Items]
Long-term debt face amount							$ 600,000,000
Long-term debt interest rate							4.60%
6.05% due 2018 [Member]
Debt Instrument [Line Items]
Long-term debt interest rate		6.05%
Long-Term Debt, retired		$ 250,000,000
Dalton Expansion Project [Member]
Debt Instrument [Line Items]
Other financing obligation			$ 235,800,000	700,000		29,800,000
Long-term debt face amount				$ 256,800,000		258,100,000
Long-term debt interest rate				9.00%
Debt Instrument, Term			35 years
Other Long-term Debt, Current				$ 2,100,000		1,900,000
Percent Of Construction Costs Capitalized				100.00%
Atlantic Sunrise Project [Member]
Debt Instrument [Line Items]
Other financing obligation	$ 810,300,000			$ 839,000,000.0		793,800,000
Additions to other financing obligations				$ 40,800,000	$ 25,000,000	20,500,000
Long-term debt interest rate				9.00%
Debt Instrument, Term	20 years
Other Long-term Debt, Current				$ 18,100,000		13,500,000
Percent Of Construction Costs Capitalized				100.00%
Property pledged as collateral
Debt Instrument [Line Items]
Total long-term debt				$ 0
Debentures
Debt Instrument [Line Items]
Total long-term debt, including current portion				207,500,000		207,500,000
Debentures \| 7.08% due 2026 [Member]
Debt Instrument [Line Items]
Total long-term debt, including current portion				7,500,000		7,500,000
Debentures \| 7.25% due 2026 [Member]
Debt Instrument [Line Items]
Total long-term debt, including current portion				200,000,000		200,000,000
Notes
Debt Instrument [Line Items]
Total long-term debt, including current portion				2,775,000,000		2,775,000,000
Notes \| 7.85% due 2026
Debt Instrument [Line Items]
Total long-term debt, including current portion				1,000,000,000		1,000,000,000
Notes \| 4.0% due 2028 [Member]
Debt Instrument [Line Items]
Total long-term debt, including current portion				400,000,000		400,000,000
Notes \| 5.4% due 2041 [Member]
Debt Instrument [Line Items]
Total long-term debt, including current portion				375,000,000		375,000,000
Notes \| 4.45% due 2042 [Member]
Debt Instrument [Line Items]
Total long-term debt, including current portion				400,000,000		400,000,000
Notes \| 4.6 % due 2048 [Member]
Debt Instrument [Line Items]
Total long-term debt, including current portion				$ 600,000,000		$ 600,000,000