Revenue Recognition - Schedule of Revenue Disaggregated by Line of Business (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) segment	Jun. 30, 2023 USD ($)
Revenue from Contract with Customer [Abstract]
Number of reportable segments | segment			3
Guarantee period			90 days
Disaggregation of Revenue [Line Items]
Total service revenues	$ 1,472,524	$ 1,639,478	$ 2,948,461	$ 3,355,813
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total service revenues	(116,466)	(114,807)	(229,280)	(240,598)
Finance and accounting
Disaggregation of Revenue [Line Items]
Total service revenues	623,120	721,391	1,265,090	1,499,224
Administrative and customer support
Disaggregation of Revenue [Line Items]
Total service revenues	190,344	211,023	390,276	430,373
Technology
Disaggregation of Revenue [Line Items]
Total service revenues	157,899	181,776	315,869	375,858
Total contract talent solutions
Disaggregation of Revenue [Line Items]
Total service revenues	854,897	999,383	1,741,955	2,064,857
Permanent placement talent solutions
Disaggregation of Revenue [Line Items]
Total service revenues	131,063	149,254	255,830	305,991
Protiviti
Disaggregation of Revenue [Line Items]
Total service revenues	$ 486,564	$ 490,841	$ 950,676	$ 984,965