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

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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 of principal amount of debt redeemed.

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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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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DEBT - Senior Notes (Detail) - USD ($)	12 Months Ended
DEBT - Senior Notes (Detail) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Nov. 30, 2018
Debt Instrument [Line Items]
Short-term debt	$ 1,694,000,000	$ 150,000,000
Percentage of principal amount that may be redeemed	100.00%
Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 4,375,000,000	4,770,000,000
Loss on extinguishment of debt		17,000,000
Senior Notes \| $400 million, 2.625% due October 1, 2019
Debt Instrument [Line Items]
Long-term debt	0	399,000,000
Face amount	$ 400,000,000
Debt instrument, stated interest rate	2.625%
Senior Notes \| $400 million, 2.50% due December 15, 2020
Debt Instrument [Line Items]
Long-term debt	$ 398,000,000	397,000,000
Face amount	$ 400,000,000
Debt instrument, stated interest rate	2.50%
Senior Notes \| $400 million, 2.90% due December 15, 2022
Debt Instrument [Line Items]
Long-term debt	$ 396,000,000	396,000,000
Face amount	$ 400,000,000
Debt instrument, stated interest rate	2.90%
Senior Notes \| $600 million, 3.15% due December 1, 2022
Debt Instrument [Line Items]
Long-term debt	$ 596,000,000	595,000,000
Face amount	$ 600,000,000
Debt instrument, stated interest rate	3.15%
Senior Notes \| $600 million, 3.85% due October 1, 2024
Debt Instrument [Line Items]
Long-term debt	$ 597,000,000	595,000,000
Face amount	$ 600,000,000
Debt instrument, stated interest rate	3.85%
Senior Notes \| $600 million, 3.95% due March 15, 2027
Debt Instrument [Line Items]
Long-term debt	$ 594,000,000	594,000,000
Face amount	$ 600,000,000
Debt instrument, stated interest rate	3.95%
Senior Notes \| $250 million, 8.15% due June 15, 2038
Debt Instrument [Line Items]
Long-term debt	$ 263,000,000	263,000,000
Face amount	$ 250,000,000
Debt instrument, stated interest rate	8.15%
Short-term debt, weighted average interest rate, at point in time	8.15%
Senior Notes \| $400 million, 4.625% due December 1, 2042
Debt Instrument [Line Items]
Long-term debt	$ 396,000,000	396,000,000
Face amount	$ 400,000,000
Debt instrument, stated interest rate	4.625%
Senior Notes \| $750 million, 4.95% due October 1, 2044
Debt Instrument [Line Items]
Long-term debt	$ 739,000,000	739,000,000
Face amount	$ 750,000,000
Debt instrument, stated interest rate	4.95%
Senior Notes \| $400 million, 4.80% due March 15, 2047
Debt Instrument [Line Items]
Long-term debt	$ 396,000,000	396,000,000
Face amount	$ 400,000,000
Debt instrument, stated interest rate	4.80%
Commercial Paper
Debt Instrument [Line Items]
Short-term debt	$ 645,000,000	150,000,000
Notes Payable to Banks
Debt Instrument [Line Items]
Short-term debt	650,000,000	0
Face amount			$ 1,000,000,000.0
Senior Notes \| $400 million, 2.625% due October 1, 2019
Debt Instrument [Line Items]
Short-term debt	399,000,000	$ 0
Face amount	$ 400,000,000
Debt instrument, stated interest rate	2.625%