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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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 outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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The cash outflow for a borrowing supported by a written promise to pay an obligation.

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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 - Notes and Debentures (Details) - USD ($)					12 Months Ended
DEBT - Notes and Debentures (Details) - USD ($)	Jun. 27, 2017	Jun. 21, 2017	Mar. 17, 2016	Jun. 15, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Apr. 15, 2016	Mar. 24, 2015	Dec. 31, 2012
Debt
Proceeds from issuance of debt		$ 599,000,000	$ 896,000,000
Repayments of notes payable					$ 535,000,000	$ 1,300,000,000	$ 500,000,000
Debt extinguishment costs					104,000,000	40,000,000	0
Debt extinguishment costs					$ 104,000,000	40,000,000	$ 0
Debt issued										$ 400,000,000
6.625% Notes and Debentures Due 15 April 2018 \| Senior notes and debentures
Debt
Interest rate (as a percent)					6.625%
Senior Notes					$ 114,000,000	$ 114,000,000
7.75% Notes and Debentures Due 1 August 2029 \| Senior notes and debentures
Debt
Interest rate (as a percent)	7.75%				7.75%	7.75%
Repayments of notes payable	$ 62,000,000
Senior Notes					$ 234,000,000	$ 296,000,000
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
Interest rate (as a percent)		3.50%
Long-term debt, gross		$ 300,000,000
Senior Notes					$ 300,000,000	0
4.5% Notes and Debentures Due May 15, 2047 \| Senior notes and debentures
Debt
Interest rate (as a percent)		4.50%			4.50%
Long-term debt, gross		$ 300,000,000
Senior Notes					$ 299,000,000	0
7.125% Notes and Debentures Due 15 March 2020 \| Senior notes and debentures
Debt
Interest rate (as a percent)	7.125%				7.125%
Repayments of notes payable	$ 299,000,000
Senior Notes					$ 201,000,000	500,000,000
5.95% Notes and Debentures Due March 15, 2022 [Member] \| Senior notes and debentures
Debt
Interest rate (as a percent)	5.95%
Repayments of notes payable	$ 74,000,000
6.5% Notes and Debentures Due 15 August 2032 \| Senior notes and debentures
Debt
Interest rate (as a percent)	6.50%				6.50%
Repayments of notes payable	$ 100,000,000
Senior Notes					$ 200,000,000	300,000,000
7.125%, 5.95%, 7.75% and 6.5% Notes and Debentures [Member]
Debt
Debt extinguishment costs					$ 107,000,000
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
Interest rate (as a percent)			3.50%
Long-term debt, gross			$ 400,000,000
Senior Notes					$ 399,000,000	399,000,000
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
Interest rate (as a percent)			4.375%
Long-term debt, gross			$ 500,000,000
Senior Notes					$ 498,000,000	498,000,000
6.125% Notes and Debentures Due October 3, 2016 \| Senior notes and debentures
Debt
Interest rate (as a percent)								6.125%
Senior Notes								$ 1,000,000,000
5.85% Notes and Debenture Due March 15, 2017 \| Senior notes and debentures
Debt
Interest rate (as a percent)								5.85%
Senior Notes								$ 300,000,000
4.8% Notes and Debentures Due 15 June 2015 \| Senior notes and debentures
Debt
Interest rate (as a percent)				4.80%
Repayments of notes payable				$ 500,000,000
4.45% Notes and Debentures Due 1 April 2025 \| Senior notes and debentures
Debt
Interest rate (as a percent)					4.45%				4.45%
Senior Notes					$ 500,000,000	$ 500,000,000
Debt issued									$ 500,000,000