CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 237	$ 237	$ 685	$ 703
Other comprehensive income (loss):
Foreign currency translation adjustment	1	(4)	(4)	1
Net deferred gain on cash flow hedges, net of taxes	3	0	3	0
Other comprehensive income (loss) income	4	(4)	(1)	1
Comprehensive income	241	233	684	704
Less: Comprehensive income attributable to noncontrolling interests	11	12	36	41
Comprehensive income attributable to Quest Diagnostics	$ 230	$ 221	$ 648	$ 663