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

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Description of any adjustments made to the stated rate to determine the effective rate.

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

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Long-Term Debt - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			9 Months Ended
	Feb. 29, 2020	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Pretax loss on retirement of debt		$ 0		$ 211	$ 295	$ 211
Secured Debt [Member]
Debt Instrument [Line Items]
Pretax loss on retirement of debt					$ 295
6.25% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Early Repayment of Senior Debt	$ 1,000
Debt Instrument, Redemption Price, Percentage	6.25%
7.50% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Early Repayment of Senior Debt	$ 2,000
Debt Instrument, Redemption Price, Percentage	7.50%
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 2,700
Debt instrument, stated interest	3.50%
Debt Instrument, Interest Rate, Effective Percentage		5.50%			5.50%
Senior Secured Three Six Four Day Term Loan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 2,000			$ 2,000
Debt Instrument, Interest Rate, Basis for Effective Rate			LIBOR rate plus 2.50%
Debt Instrument, Interest Rate, Effective Percentage			2.50%