Revenue Recognition - Schedule of Revenue Disaggregated by Line of Business (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) segment	Sep. 30, 2023 USD ($)
Revenue from Contract with Customer [Abstract]
Number of reportable segments | segment			3
Guarantee period			90 days
Disaggregation of Revenue [Line Items]
Total service revenues	$ 1,465,004	$ 1,563,812	$ 4,413,465	$ 4,919,625
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total service revenues	(122,321)	(100,630)	(351,601)	(341,228)
Finance and accounting
Disaggregation of Revenue [Line Items]
Total service revenues	614,131	676,588	1,879,221	2,175,812
Administrative and customer support
Disaggregation of Revenue [Line Items]
Total service revenues	178,409	196,565	568,685	626,938
Technology
Disaggregation of Revenue [Line Items]
Total service revenues	160,184	170,574	476,053	546,432
Total contract talent solutions
Disaggregation of Revenue [Line Items]
Total service revenues	830,403	943,097	2,572,358	3,007,954
Permanent placement talent solutions
Disaggregation of Revenue [Line Items]
Total service revenues	123,275	139,931	379,105	445,922
Protiviti
Disaggregation of Revenue [Line Items]
Total service revenues	$ 511,326	$ 480,784	$ 1,462,002	$ 1,465,749