CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Net revenues	$ 2,338	$ 2,453	$ 4,669	$ 5,064
Operating costs and expenses and other operating income:
Cost of services	1,546	1,611	3,106	3,257
Selling, general and administrative	416	422	855	847
Amortization of intangible assets	28	27	54	54
Other operating expense, net	0	5	1	5
Total operating costs and expenses, net	1,990	2,065	4,016	4,163
Operating income	348	388	653	901
Other income (expense):
Interest expense, net	(37)	(36)	(72)	(73)
Other income (expense), net	6	(29)	13	(53)
Total non-operating expense, net	(31)	(65)	(59)	(126)
Income before income taxes and equity in earnings of equity method investees	317	323	594	775
Income tax expense	(75)	(77)	(140)	(187)
Equity in earnings of equity method investees, net of taxes	7	4	12	35
Net income	249	250	466	623
Less: Net income attributable to noncontrolling interests	14	16	29	34
Net income attributable to Quest Diagnostics	$ 235	$ 234	$ 437	$ 589
Earnings per share attributable to Quest Diagnostics’ common stockholders:
Basic (in dollars per share)	$ 2.08	$ 2.00	$ 3.88	$ 4.97
Diluted (in dollars per share)	$ 2.05	$ 1.96	$ 3.83	$ 4.88
Weighted average common shares outstanding:
Basic (in Shares)	112	117	112	118
Diluted (in Shares)	114	119	114	120