Cash Proceeds Received from Derivatives

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In the event of a change in control, as defined in the related agreements, debt obligations totaling may be declared immediately due and payable.

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- Definition

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.

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Gross amount of debt extinguished.

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No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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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 after 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 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 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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Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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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 (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended	12 Months Ended
Debt (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 24, 2017
Debt Instrument [Line Items]
Loss on early extinguishment of debt					$ 0	$ (51,000,000)	$ 0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax					0	47,000,000	0
Repayments of Long-term Debt					0	2,764,000,000	$ 1,000,000
Other Long-term Debt, Noncurrent	$ 5,536,000,000	$ 5,536,000,000			5,536,000,000	5,536,000,000
Unamortized Discount	(10,000,000)	(10,000,000)			(8,000,000)	(10,000,000)
Unamortized Debt Issuance Expense	(32,000,000)	(32,000,000)			(29,000,000)	(32,000,000)
Total long-term debt due after one year	5,494,000,000	5,494,000,000			5,499,000,000	5,494,000,000
Debt Immediately Due If Change In Control					236,000,000
Proceeds from Issuance of Debt		990,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2019					0
2020					600,000,000
2021					0
2022					1,035,000,000
2023					201,000,000
Thereafter					3,700,000,000
Other Long-term Debt, Noncurrent	5,536,000,000	5,536,000,000			$ 5,536,000,000	5,536,000,000
Senior Unsecured Notes Due 2027 [Member]
Debt Instrument [Line Items]
Other Long-term Debt, Noncurrent								$ 1,000,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent								$ 1,000,000,000
Senior Unsecured Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					2.70%
Other Long-term Debt, Noncurrent	600,000,000	600,000,000			$ 600,000,000	600,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	600,000,000	600,000,000			$ 600,000,000	600,000,000
Senior Unsecured Notes Due 2022 [A] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					2.80%
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Senior Unsecured Notes Due 2022 [B] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					9.375%
Other Long-term Debt, Noncurrent	32,000,000	32,000,000			$ 32,000,000	32,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	32,000,000	32,000,000			32,000,000	32,000,000
Series Medium Term Notes Due 2022 [Member]
Debt Instrument [Line Items]
Other Long-term Debt, Noncurrent	3,000,000	3,000,000			3,000,000	3,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	3,000,000	3,000,000			$ 3,000,000	3,000,000
Senior Unsecured Notes Due 2023 [A] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					8.50%
Other Long-term Debt, Noncurrent	70,000,000	70,000,000			$ 70,000,000	70,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	70,000,000	70,000,000			$ 70,000,000	70,000,000
Senior Unsecured Notes Due 2023 [B] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					8.125%
Other Long-term Debt, Noncurrent	131,000,000	131,000,000			$ 131,000,000	131,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	131,000,000	131,000,000			$ 131,000,000	131,000,000
Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					3.85%
Other Long-term Debt, Noncurrent	900,000,000	900,000,000			$ 900,000,000	900,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	900,000,000	900,000,000			$ 900,000,000	900,000,000
Senior Unsecured Notes Due 2032 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					6.80%
Other Long-term Debt, Noncurrent	550,000,000	550,000,000			$ 550,000,000	550,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	550,000,000	550,000,000			$ 550,000,000	550,000,000
Notes Due 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					4.40%
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Senior Unsecured Notes Due 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					6.60%
Other Long-term Debt, Noncurrent	750,000,000	750,000,000			$ 750,000,000	750,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	750,000,000	750,000,000			$ 750,000,000	750,000,000
Senior Unsecured Notes Due 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					5.20%
Other Long-term Debt, Noncurrent	500,000,000	500,000,000			$ 500,000,000	500,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	$ 500,000,000	$ 500,000,000			$ 500,000,000	$ 500,000,000
Obligation Relating To Revenue Bonds Due 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.125%	5.125%				5.125%
Extinguishment of Debt, Amount	$ 1,000,000,000
Unsecured Debt [Member]
Debt Instrument [Line Items]
Loss on early extinguishment of debt						$ (46,000,000)
Repayments of Long-term Debt						1,760,000,000
Municipal Revenue Bonds Due 2037 [Member] \| The Parish [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 1,000,000,000	$ 1,000,000,000				$ 1,000,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.75%	3.75%				3.75%
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax						$ 46,000,000
Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Debt Instrument [Line Items]
Cash Proceeds Received from Derivatives				$ 54,000,000		$ 54,000,000
Senior Unsecured Notes Due 2019 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			7.50%	7.50%
Repayments of Long-term Debt			$ 228,000,000
Senior Unsecured Notes Due 2018 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.90%	5.90%
Repayments of Long-term Debt			$ 854,000,000
Senior Unsecured Notes Due 2017 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.00%	6.00%
Repayments of Long-term Debt			$ 682,000,000