UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues:
Total revenues	$ 1,529,422	$ 1,365,696	$ 4,458,836	$ 4,070,983
Cost of revenues: (exclusive of items shown separately below)
Total cost of revenues	1,055,599	943,951	3,062,211	2,822,977
Selling, general and administrative expenses	177,846	171,019	557,590	505,154
Accretion of environmental liabilities	3,618	3,388	10,139	10,281
Depreciation and amortization	100,063	92,970	295,632	267,425
Income from operations	192,296	154,368	533,264	465,146
Other (expense) income, net	(1,123)	334	(2,431)	(833)
Loss on early extinguishment of debt	0	0	0	(2,362)
Interest expense, net of interest income of $5,391, $2,877, $13,257, and $7,833, respectively	(35,779)	(29,696)	(100,767)	(80,400)
Income before provision for income taxes	155,394	125,006	430,066	381,551
Provision for income taxes	40,181	33,666	111,741	102,044
Net income	$ 115,213	$ 91,340	$ 318,325	$ 279,507
Earnings per share:
Basic (in dollars per share)	$ 2.14	$ 1.69	$ 5.90	$ 5.17
Diluted (in dollars per share)	$ 2.12	$ 1.68	$ 5.87	$ 5.14
Shares used to compute earnings per share - Basic (in shares)	53,951	54,122	53,936	54,097
Shares used to compute earnings per share - Diluted (in shares)	54,229	54,419	54,229	54,411
Service revenues
Revenues:
Total revenues	$ 1,278,955	$ 1,129,216	$ 3,719,183	$ 3,341,539
Cost of revenues: (exclusive of items shown separately below)
Total cost of revenues	872,829	765,004	2,539,569	2,288,199
Product revenues
Revenues:
Total revenues	250,467	236,480	739,653	729,444
Cost of revenues: (exclusive of items shown separately below)
Total cost of revenues	$ 182,770	$ 178,947	$ 522,642	$ 534,778