Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Revenues	$ 5,031,819	$ 4,428,826
Cost of services	4,408,325	3,855,631
Gross profit	623,494	573,195
Equity in earnings of integral unconsolidated affiliates	12,334	9,620
Selling, general and administrative expenses	(402,340)	(384,552)
Amortization of intangible assets	(77,511)	(72,403)
Change in fair value of contingent consideration liabilities	(623)	0
Operating income	155,354	125,860
Interest and other financing expenses	(41,072)	(41,693)
Interest income	8,023	1,516
Other income, net	24,882	7,866
Income before income taxes	147,187	93,549
Provision for (benefit from) income taxes	21,096	(3,421)
Net income	126,091	96,970
Less: Net income attributable to non-controlling interests	7,731	1,924
Net income attributable to common stock	$ 118,360	$ 95,046
Earnings per share attributable to common stock:
Basic (in dollars per share)	$ 0.81	$ 0.66
Diluted (in dollars per share)	$ 0.79	$ 0.64
Shares used in computing earnings per share:
Weighted average basic shares outstanding (in shares)	145,936	144,467
Weighted average diluted shares outstanding (in shares)	149,350	148,661