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.

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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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Percentage of principal amount of debt redeemed.

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Gross amount of debt extinguished.

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Debt Instrument, Bonds, Principal Amount Remarketed

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Long-Term Debt (GO Zone Bonds) (Details) - Senior Notes [Member] - USD ($) $ in Millions		1 Months Ended
	Aug. 01, 2020	Nov. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Nov. 30, 2017	Dec. 31, 2010	Jul. 02, 2010
6 1/2% GO Zone Senior Notes Due 2035 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 0	$ 89		$ 89
Stated interest rate (percent)			6.50%
Extinguishment of Debt, Amount		$ 89
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed		100.00%
6 1/2% GO Zone Senior Notes Due 2029 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 0	100
Debt Instrument, Face Amount							$ 100
Stated interest rate (percent)			6.50%
Extinguishment of Debt, Amount	$ 100
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed	100.00%
Go Zone 3.50% Bonds Due 2032 [Member]
Debt Instrument [Line Items]
Amount of bonds remarketed					$ 250
3.50% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 250	$ 250
Stated interest rate (percent)			3.50%