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

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Percentage of principal amount of debt redeemed.

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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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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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DEBT - Senior Notes (Details) - Senior Notes - USD ($)	1 Months Ended		9 Months Ended
DEBT - Senior Notes (Details) - Senior Notes - USD ($)	Dec. 31, 2017	Mar. 31, 2017	Sep. 30, 2018
Debt Instrument [Line Items]
Long-term debt	$ 4,770,000,000		$ 4,774,000,000
Proceeds from debt, net of discounts and offering expenses	$ 794,000,000	$ 991,000,000
Percentage of principal amount redeemed	100.00%
Early repayment of senior debt	$ 829,000,000
Loss on extinguishment of debt	17,000,000
Redemption price, percentage			100.00%
$400 million, 2.625% due October 1, 2019
Debt Instrument [Line Items]
Long-term debt	399,000,000		$ 399,000,000
Face amount			$ 400,000,000
Stated interest rate			2.625%
$400 million, 2.50% due December 15, 2020
Debt Instrument [Line Items]
Long-term debt	397,000,000		$ 398,000,000
Face amount	$ 400,000,000		$ 400,000,000
Stated interest rate	2.50%		2.50%
$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		$ 400,000,000
Stated interest rate	2.90%		2.90%
$600 million, 3.15% due December 1, 2022
Debt Instrument [Line Items]
Long-term debt	$ 595,000,000		$ 597,000,000
Face amount			$ 600,000,000
Stated interest rate			3.15%
$600 million, 3.85% due October 1, 2024
Debt Instrument [Line Items]
Long-term debt	595,000,000		$ 596,000,000
Face amount			$ 600,000,000
Stated interest rate			3.85%
$600 million, 3.95% due March 15, 2027
Debt Instrument [Line Items]
Long-term debt	594,000,000		$ 595,000,000
Face amount		$ 600,000,000	$ 600,000,000
Stated interest rate		3.95%	3.95%
$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
Stated interest rate			8.15%
$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
Stated interest rate			4.625%
$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
Stated interest rate			4.95%
$400 million, 4.80% due March 15, 2047
Debt Instrument [Line Items]
Long-term debt	396,000,000		$ 395,000,000
Face amount		$ 400,000,000	$ 400,000,000
Stated interest rate		4.80%	4.80%
$300 million, 6.30% due August 2018
Debt Instrument [Line Items]
Face amount	$ 300,000,000
Stated interest rate	6.30%
$500 million, 7.20% due June 2018
Debt Instrument [Line Items]
Face amount	$ 500,000,000
Stated interest rate	7.20%