CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Revenues	$ 1,165,465	$ 1,210,941
Operating expenses:
Cost of revenues (exclusive of depreciation and amortization)	834,334	855,901
Selling, general and administrative expenses	198,453	211,887
Depreciation and amortization expense	22,146	22,782
Income from operations	110,532	120,371
Interest and other income, net	15,042	11,521
Foreign exchange loss	(1,919)	(4,608)
Income before provision for income taxes	123,655	127,284
Provision for income taxes	7,412	24,992
Net income	$ 116,243	$ 102,292
Net income per share:
Basic (in usd per share)	$ 2.01	$ 1.77
Diluted (in usd per share)	$ 1.97	$ 1.73
Shares used in calculation of net income per share:
Basic (in shares)	57,837	57,702
Diluted (in shares)	58,931	59,298