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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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Date the credit facility terminates, in CCYY-MM-DD format.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Unamortized discount, capitalized debt expense and fair value adjustment

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LONG-TERM DEBT - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Line of Credit Facility, Expiration Date			Mar. 31, 2022
Long-term Debt, Gross			$ 5,933	$ 6,008
Proceeds from issuance of long-term debt			0	225	$ 1,698
Unamortized discounts, capitalized debt expense and fair value adjustments			26
7.00 percent debentures due 2018 [Member]
Debt Instrument [Line Items]
Senior Notes			$ 0	$ 62
Repayments of debt	$ 62
Interest rate, stated			7.00%
Debt, Maturity Date			Dec. 31, 2018
Variable rate term loan credit facility matures 2020
Debt Instrument [Line Items]
Line of Credit Facility, Expiration Date			Dec. 31, 2020
Repayments of debt		$ 550
Interest rate, stated			0.00%
Variable rate term loan credit facility matures 2026
Debt Instrument [Line Items]
Line of Credit Facility, Expiration Date			Dec. 31, 2026
Proceeds from issuance of long-term debt		225
Interest rate, stated			4.122%
Cash and Cash Equivalents \| Variable rate term loan credit facility matures 2020
Debt Instrument [Line Items]
Repayments of debt		$ 325