Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Total Revenue	$ 437,620	$ 402,725	$ 1,291,103	$ 1,169,564
Flex revenue
Disaggregation of Revenue [Line Items]
Total Revenue	422,968	389,173	1,244,533	1,134,382
Direct Hire revenue
Disaggregation of Revenue [Line Items]
Total Revenue	14,652	13,552	46,570	35,182
Technology
Disaggregation of Revenue [Line Items]
Total Revenue	390,496	337,230	1,134,996	927,518
Technology | Flex revenue
Disaggregation of Revenue [Line Items]
Total Revenue	382,072	330,170	1,109,294	909,599
Technology | Direct Hire revenue
Disaggregation of Revenue [Line Items]
Total Revenue	8,424	7,060	25,702	17,919
FA
Disaggregation of Revenue [Line Items]
Total Revenue	47,124	65,495	156,107	242,046
FA | Flex revenue
Disaggregation of Revenue [Line Items]
Total Revenue	40,896	59,003	135,239	224,783
FA | Direct Hire revenue
Disaggregation of Revenue [Line Items]
Total Revenue	$ 6,228	$ 6,492	$ 20,868	$ 17,263