CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS Percentage	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues
Revenues (as a percent)	100.00%	100.00%	100.00%	100.00%
Cost of revenues
Labor and other operating expenses (as a percent)	45.00%	54.50%	46.80%	55.10%
Depreciation, depletion and amortization (as a percent)	6.80%	7.90%	7.50%	8.10%
Total cost of revenues (as a percent)	51.80%	62.40%	54.30%	63.20%
Gross profit (as a percent)	48.20%	37.60%	45.70%	36.80%
Selling, general and administrative expenses (as a percent)	5.60%	5.80%	6.20%	6.00%
Operating profit (as a percent)	42.60%	31.80%	39.50%	30.80%
Other (income) expense, net
Other (income) expense, net (as a percent)	(3.50%)	(2.90%)	(3.50%)	(2.60%)
Income before income tax expense (as a percent)	46.10%	34.70%	43.00%	33.40%
Income tax expense (as a percent)	8.80%	7.00%	8.60%	6.70%
Net income (as a percent)	37.30%	27.70%	34.40%	26.70%