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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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- Definition

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

+ References

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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Long-Term Debt - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Aug. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Debt Instrument [Line Items]
Pretax loss on retirement of debt		$ (9,000,000)	$ (39,000,000)	$ (9,000,000)	$ (39,000,000)
Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 2,000,000,000
Senior Notes [Member] \| 5.375% Senior Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 1,000,000,000
Debt instrument, stated interest	5.375%
Senior Notes [Member] \| 5.625% Senior Notes Due 2028 [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 1,000,000,000
Debt instrument, stated interest	5.625%
Senior Notes [Member] \| Senior Notes Due2019 [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest	3.75%
Proceeds from new term loan	$ 1,500,000,000
Pretax loss on retirement of debt	$ 9,000,000