SEGMENT INFORMATION - Narrative (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2017 USD ($) segment
Segment Reporting Information [Line Items]
Number of reportable segments | segment		2
Service revenues, percent of total revenues		1.00%
UNITED STATES
Segment Reporting Information [Line Items]
Intersegment sales increase | $	$ 16	$ 29