CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Net revenues	$ 2,366	$ 2,331
Operating costs and expenses and other operating income:
Cost of services	1,595	1,560
Selling, general and administrative	440	439
Amortization of intangible assets	29	26
Other operating expense, net	2	1
Total operating costs and expenses, net	2,066	2,026
Operating income	300	305
Other income (expense):
Interest expense, net	(43)	(35)
Other income, net	9	7
Total non-operating expense, net	(34)	(28)
Income before income taxes and equity in earnings of equity method investees	266	277
Income tax expense	(66)	(65)
Equity in earnings of equity method investees, net of taxes	8	5
Net income	208	217
Less: Net income attributable to noncontrolling interests	14	15
Net income attributable to Quest Diagnostics	$ 194	$ 202
Earnings per share attributable to Quest Diagnostics’ common stockholders:
Basic (in dollars per share)	$ 1.74	$ 1.80
Diluted (in dollars per share)	$ 1.72	$ 1.78
Weighted average common shares outstanding:
Basic (in Shares)	111	112
Diluted (in Shares)	112	113