CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
Revenue from Contract with Customer, Product and Service [Extensible List]	Service [Member]	Service [Member]
Revenue from services	$ 622,707	$ 788,732
Operating expenses:
Direct operating expenses	483,284	613,938
Selling, general and administrative expenses	84,260	76,853
Bad debt expense	4,908	2,369
Depreciation and amortization	4,904	2,719
Restructuring costs	429	480
Legal settlement charges	1,125	0
Impairment charges	0	1,741
Total operating expenses	578,910	698,100
Income from operations	43,797	90,632
Other expenses (income):
Interest expense	3,690	3,521
Other income, net	(12)	(8)
Income before income taxes	40,119	87,119
Income tax expense	10,683	25,136
Net income attributable to common stockholders	29,436	61,983
Other comprehensive income:
Unrealized foreign currency translation gain (loss), net of tax	7	(11)
Comprehensive income	$ 29,443	$ 61,972
Net income per share attributable to common stockholders - Basic (in dollars per share)	$ 0.82	$ 1.67
Net income per share attributable to common stockholders - Diluted (in dollars per share)	$ 0.81	$ 1.63
Weighted average common shares outstanding:
Basic (shares)	35,864	37,028
Diluted (shares)	36,560	37,973