Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Income Statement [Abstract]
Revenues	$ 6,233,334	$ 5,031,819
Cost of services	5,399,297	4,408,325
Gross profit	834,037	623,494
Equity in earnings of integral unconsolidated affiliates	12,929	12,334
Selling, general and administrative expenses	(493,966)	(402,340)
Amortization of intangible assets	(109,562)	(77,511)
Change in fair value of contingent consideration liabilities	(4,357)	(623)
Operating income	239,081	155,354
Interest and other financing expenses	(54,312)	(41,072)
Interest income	3,841	8,023
Other income, net	239	24,882
Income before income taxes	188,849	147,187
Provision for income taxes	39,880	21,096
Net income	148,969	126,091
Less: Net income attributable to non-controlling interests	4,711	7,731
Net income attributable to common stock	$ 144,258	$ 118,360
Earnings per share attributable to common stock:
Basic (in dollars per share)	$ 0.97	$ 0.81
Diluted (in dollars per share)	$ 0.96	$ 0.79
Shares used in computing earnings per share:
Weighted average basic shares outstanding (in shares)	148,274	145,936
Weighted average diluted shares outstanding (in shares)	150,964	149,350