CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
CONSOLIDATED STATEMENTS OF OPERATIONS
Revenues	$ 415,858	$ 375,507	$ 892,526	$ 660,131
Cost of revenues	265,786	260,917	571,036	469,754
Selling, general and administrative expenses	43,604	35,879	85,801	72,119
Pension settlement charges	911		18,286
Depreciation and amortization	26,203	20,094	50,328	39,560
Gain on disposition of assets, net	(3,015)	(1,798)	(5,951)	(4,752)
Operating income	82,369	60,415	173,026	83,450
Interest expense	(73)	(222)	(145)	(400)
Interest income	2,698	128	4,553	143
Other income, net	631	79	1,392	583
Income before income taxes	85,625	60,400	178,826	83,776
Income tax provision	20,612	13,461	42,289	21,758
Net income	$ 65,013	$ 46,939	$ 136,537	$ 62,018
Earnings per share
Basic (in dollars per share)	$ 0.30	$ 0.22	$ 0.63	$ 0.29
Diluted (in dollars per share)	$ 0.30	$ 0.22	$ 0.63	$ 0.29