CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 753	$ 592	$ 883
Other comprehensive (loss) income:
Currency translation	(15)	(7)	(27)
Market valuation, net of tax	0	(1)	(1)
Net deferred loss on cash flow hedges, net of tax	3	(10)	2
Other	1	(1)	4
Other comprehensive loss	(11)	(19)	(22)
Comprehensive income	742	573	861
Less: Comprehensive income attributable to noncontrolling interests	44	36	34
Comprehensive income attributable to Quest Diagnostics	$ 698	$ 537	$ 827