Increase in percentage points added to the reference rate to compute the variable rate on the debt instrument.

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.

+ References

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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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.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

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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Balance Type:	debit
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- Definition

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

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

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Debt (Components of Debt) (Details) - USD ($) $ in Millions	1 Months Ended
Debt (Components of Debt) (Details) - USD ($) $ in Millions	Jul. 31, 2016	Dec. 31, 2019	Dec. 31, 2018	Jul. 31, 2018	Jan. 31, 2015
Debt Instrument [Line Items]
Debt Instrument		$ 2,262	$ 2,342
Unamortized Issuance Expense		(19)	(23)
Unamortized Debt Discount		(1)	(1)
Total		$ 2,242	2,318
Stated interest rate		7.75%
Debt issuance costs, line of credit		$ 11	11
Line of Credit \| 2018 Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, variable interest rate		4.31%
Line of Credit \| 2018 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt Instrument		$ 34
Unamortized Issuance Expense		0
Unamortized Debt Discount		0
Total		$ 34
Senior Notes \| LIBOR
Debt Instrument [Line Items]
Increase in basis spread	1.75%
Senior Notes \| 4.05% Senior Notes Due January 2020
Debt Instrument [Line Items]
Debt Instrument			52
Unamortized Issuance Expense			0
Unamortized Debt Discount			0
Total			$ 52
Stated interest rate	5.80%	4.05%	4.05%	5.30%	4.05%
Senior Notes \| 4.10% Senior Notes Due January March 2022
Debt Instrument [Line Items]
Debt Instrument		$ 213	$ 213
Unamortized Issuance Expense		(1)	(1)
Unamortized Debt Discount		0	0
Total		$ 212	212
Stated interest rate		4.10%
Senior Notes \| 4.95% Senior Notes Due January 2025
Debt Instrument [Line Items]
Debt Instrument		$ 892	927
Unamortized Issuance Expense		(5)	(7)
Unamortized Debt Discount		(1)	(1)
Total		$ 886	919
Stated interest rate	6.70%	4.95%		6.20%	4.95%
Senior Notes \| 7.50% Senior Notes Due April 2026
Debt Instrument [Line Items]
Debt Instrument		$ 639	650
Unamortized Issuance Expense		(7)	(8)
Unamortized Debt Discount		0	0
Total		$ 632	642
Stated interest rate		7.50%
Senior Notes \| 7.75% Senior Notes Due October 2027
Debt Instrument [Line Items]
Debt Instrument		$ 484	500
Unamortized Issuance Expense		(6)	(7)
Unamortized Debt Discount		0	0
Total		$ 478	493
Stated interest rate		7.75%
Term Loan \| 2018 Term Loan Facility Due April 2023
Debt Instrument [Line Items]
Debt Instrument			0
Unamortized Issuance Expense			0
Unamortized Debt Discount			0
Total			$ 0
Debt variable rate			3.92%