Revenue Recognition - Schedule of Revenue Disaggregated by Line of Business (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) segment	Mar. 31, 2023 USD ($)
Revenue from Contract with Customer [Abstract]
Number of reportable segments | segment	3
Guarantee period	90 days
Disaggregation of Revenue [Line Items]
Total service revenues	$ 1,475,937	$ 1,716,335
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total service revenues	(112,814)	(125,791)
Finance and accounting
Disaggregation of Revenue [Line Items]
Total service revenues	641,970	777,833
Administrative and customer support
Disaggregation of Revenue [Line Items]
Total service revenues	199,932	219,350
Technology
Disaggregation of Revenue [Line Items]
Total service revenues	157,970	194,082
Total contract talent solutions
Disaggregation of Revenue [Line Items]
Total service revenues	887,058	1,065,474
Permanent placement talent solutions
Disaggregation of Revenue [Line Items]
Total service revenues	124,767	156,737
Protiviti
Disaggregation of Revenue [Line Items]
Total service revenues	$ 464,112	$ 494,124