CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 373	$ 490
Other comprehensive income (loss):
Foreign currency translation adjustment	(2)	(3)
Net change in available-for-sale debt securities, net of taxes	0	(7)
Other comprehensive loss	(2)	(10)
Comprehensive income	371	480
Less: Comprehensive income attributable to noncontrolling interests	18	21
Comprehensive income attributable to Quest Diagnostics	$ 353	$ 459