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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Amount, after accumulated amortization, of debt discount (premium).

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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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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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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DEBT - Senior Notes (Details) - USD ($)	1 Months Ended	9 Months Ended
DEBT - Senior Notes (Details) - USD ($)	Mar. 31, 2017	Sep. 30, 2017	Dec. 31, 2016	Dec. 31, 2008
Debt Instrument [Line Items]
Short-term debt		$ 953,000,000	$ 300,000,000
Total debt		4,930,000,000	4,092,000,000
Senior Notes
Debt Instrument [Line Items]
Long-term debt		$ 3,977,000,000	3,792,000,000
Proceeds from debt, net of discounts and offering expenses	$ 991,000,000
Redemption price, percentage		100.00%
Unamortized discount (premium)		$ 19,000,000	23,000,000	$ 103,000,000
Senior Notes \| $500 million, 7.20% due June 15, 2018
Debt Instrument [Line Items]
Long-term debt		0	501,000,000
Face amount		$ 500,000,000
Stated interest rate		7.20%
Senior Notes \| $300 million, 6.30% due August 1, 2018
Debt Instrument [Line Items]
Long-term debt		$ 0	304,000,000
Face amount		$ 300,000,000
Stated interest rate		6.30%
Senior Notes \| $400 million, 2.625% due October 1, 2019
Debt Instrument [Line Items]
Long-term debt		$ 399,000,000	398,000,000
Face amount		$ 400,000,000
Stated interest rate		2.625%
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
Stated interest rate		3.15%
Senior Notes \| $600 million, 3.85% due October 1, 2024
Debt Instrument [Line Items]
Long-term debt		$ 595,000,000	595,000,000
Face amount		$ 600,000,000
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	0
Face amount	$ 600,000,000	$ 600,000,000
Stated interest rate	3.95%	3.95%
Senior Notes \| $250 million, 8.15% due June 15, 2038
Debt Instrument [Line Items]
Long-term debt		$ 263,000,000	264,000,000
Face amount		$ 250,000,000
Stated interest rate		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
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
Stated interest rate		4.95%
Senior Notes \| $400 million, 4.80% due March 15, 2047
Debt Instrument [Line Items]
Long-term debt		$ 395,000,000	0
Face amount		$ 400,000,000
Stated interest rate		4.80%
Commercial paper
Debt Instrument [Line Items]
Short-term debt		$ 150,000,000	300,000,000
Senior Notes \| $500 million, 7.20% due June 15, 2018
Debt Instrument [Line Items]
Short-term debt		501,000,000	0
Senior Notes \| $300 million, 6.30% due August 1, 2018
Debt Instrument [Line Items]
Short-term debt		$ 302,000,000	$ 0