CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Net revenues	$ 1,943	$ 1,906	$ 3,842	$ 3,769
Operating costs and expenses and other operating income:
Cost of services	1,170	1,155	2,335	2,299
Selling, general and administrative	437	430	874	872
Amortization of intangible assets	18	17	35	36
Gain on disposition of business	0	(118)	0	(118)
Other operating (income) expense, net	(1)	0	0	1
Total operating costs and expenses, net	1,624	1,484	3,244	3,090
Operating income	319	422	598	679
Other income (expense):
Interest expense, net	(38)	(34)	(74)	(70)
Other income (expense), net	11	(5)	14	(54)
Total non-operating expenses, net	(27)	(39)	(60)	(124)
Income before income taxes and equity in earnings of equity method investees	292	383	538	555
Income tax expense	(94)	(183)	(172)	(250)
Equity in earnings of equity method investees, net of taxes	9	9	16	19
Net income	207	209	382	324
Less: Net income attributable to noncontrolling interests	14	14	25	26
Net income attributable to Quest Diagnostics	$ 193	$ 195	$ 357	$ 298
Earnings per share attributable to Quest Diagnostics’ common stockholders:
Basic (per share)	$ 1.40	$ 1.38	$ 2.59	$ 2.10
Diluted (per share)	$ 1.37	$ 1.37	$ 2.53	$ 2.08
Weighted average common shares outstanding:
Basic (in Shares)	137	140	137	141
Diluted (in Shares)	140	142	140	143
Dividends per common share	$ 0.45	$ 0.40	$ 0.90	$ 0.80