LONG-TERM DEBT - SCHEDULE OF LONG-TERM DEBT (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Total	$ 626		$ 683
Less debt issuance costs	(3)		(3)
Less current portion	117		114
Long-term debt, less current portion	$ 509		$ 569
Weighted-average fixed-interest rate	5.70%		5.70%
Weighted-average variable-interest rate	2.10%		1.80%
Repayments of Long-term Debt	$ 57	$ 58
Fixed-rate notes payable due through 2024 [Member]
Debt Instrument [Line Items]
Total	474		$ 520
Variable-rate notes payable due through 2025 [Member]
Debt Instrument [Line Items]
Total	$ 155		$ 166