CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 908	$ 1,015	$ 2,080
Other comprehensive income (loss):
Foreign currency translation adjustment	5	(8)	13
Net change in available-for-sale debt securities, net of taxes	0	0	(7)
Net deferred gains on cash flow hedges, net of taxes	2	1	1
Other comprehensive income (loss)	7	(7)	7
Comprehensive income	915	1,008	2,087
Less: Comprehensive income attributable to noncontrolling interests	54	69	85
Comprehensive income attributable to Quest Diagnostics	$ 861	$ 939	$ 2,002