UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenues:
Total revenues	$ 1,376,695	$ 1,307,387
Cost of revenues: (exclusive of items shown separately below)
Total cost of revenues	971,070	931,514
Selling, general and administrative expenses	181,868	166,753
Accretion of environmental liabilities	3,217	3,407
Depreciation and amortization	95,065	84,758
Income from operations	125,475	120,955
Other (expense) income, net	(1,141)	116
Loss on early extinguishment of debt	0	(2,362)
Interest expense, net of interest income of $3,514 and $2,955, respectively	(28,539)	(20,632)
Income before provision for income taxes	95,795	98,077
Provision for income taxes	25,963	25,676
Net income	$ 69,832	$ 72,401
Earnings per share:
Basic (in dollars per share)	$ 1.29	$ 1.34
Diluted (in dollars per share)	$ 1.29	$ 1.33
Shares used to compute earnings per share - Basic (in shares)	53,930	54,076
Shares used to compute earnings per share - Diluted (in shares)	54,213	54,404
Service revenues
Revenues:
Total revenues	$ 1,151,858	$ 1,053,233
Cost of revenues: (exclusive of items shown separately below)
Total cost of revenues	816,349	751,595
Product revenues
Revenues:
Total revenues	224,837	254,154
Cost of revenues: (exclusive of items shown separately below)
Total cost of revenues	$ 154,721	$ 179,919