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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

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Amount of long-term debt classified as other.

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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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DEBT - Tabular Disclosure - Notes and Debentures and Other (Details) - USD ($) $ in Millions	Dec. 31, 2018	Apr. 16, 2018	Dec. 31, 2017	Jun. 27, 2017	Jun. 21, 2017	Mar. 17, 2016
Debt
Other	$ 38		$ 33
Debt Issuance Costs, Net	(17)		(19)
Total long-term debt, current and non-current	2,979		3,085
Less: Current portion	8		116
Total long-term debt	2,971		2,969
6.625% Notes and Debentures Due 15 April 2018
Debt
Interest rate (as a percent)		6.625%
6.625% Notes and Debentures Due 15 April 2018 \| Senior notes and debentures
Debt
Notes and debentures	$ 0		114
Interest rate (as a percent)	6.625%
7.125% Notes and Debentures Due 15 March 2020 \| Senior notes and debentures
Debt
Notes and debentures	$ 201		201
Interest rate (as a percent)	7.125%			7.125%
3.5% Notes and Debentures Due April 1, 2021
Debt
Interest rate (as a percent)	3.50%
3.5% Notes and Debentures Due April 1, 2021 \| Senior notes and debentures
Debt
Notes and debentures	$ 399		399
Interest rate (as a percent)						3.50%
5.95% Notes and Debentures Due 15 March 2022 \| Senior notes and debentures
Debt
Notes and debentures	$ 326		326
Interest rate (as a percent)	5.95%
4.45% Notes and Debentures Due 1 April 2025 \| Senior notes and debentures
Debt
Notes and debentures	$ 500		500
Interest rate (as a percent)	4.45%
4.375% Notes and Debentures Due April 1, 2026
Debt
Interest rate (as a percent)	4.375%
4.375% Notes and Debentures Due April 1, 2026 \| Senior notes and debentures
Debt
Notes and debentures	$ 498		498
Interest rate (as a percent)						4.375%
3.5% Notes and Debentures Due November 15, 2027
Debt
Interest rate (as a percent)	3.50%
3.5% Notes and Debentures Due November 15, 2027 \| Senior notes and debentures
Debt
Notes and debentures	$ 300		300
Interest rate (as a percent)					3.50%
7.75% Notes and Debentures Due 1 August 2029 \| Senior notes and debentures
Debt
Notes and debentures	$ 235		$ 234
Interest rate (as a percent)	7.75%		7.75%	7.75%
6.5% Notes and Debentures Due 15 August 2032 \| Senior notes and debentures
Debt
Notes and debentures	$ 200		$ 200
Interest rate (as a percent)	6.50%			6.50%
4.5% Notes and Debentures Due May 15, 2047 \| Senior notes and debentures
Debt
Notes and debentures	$ 299		$ 299
Interest rate (as a percent)	4.50%				4.50%