UNAUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net income	$ 18,939	$ 23,163
Adjustments to reconcile net income to net cash flows provided by operating activities:
Depreciation and amortization of property and equipment	14,602	12,763
Amortization of intangible assets	1,228	1,226
Stock-based compensation expense	1,917	1,982
Gain on sale of property and equipment	(1,489)	(1,224)
Other non-cash items	656	62
Changes in operating assets and liabilities:
Accounts receivable, net	(6,009)	53,819
Contract assets, net	(30,962)	(31,868)
Receivable for insurance claims in excess of deductibles	197	(601)
Other assets	13,409	15,921
Accounts payable	(30,990)	(19,142)
Contract liabilities	30,758	(6,312)
Accrued self-insurance	(4,426)	(2,561)
Other liabilities	(140)	(10,070)
Net cash flows provided by operating activities	7,690	37,158
Cash flows from investing activities:
Proceeds from sale of property and equipment	1,879	1,539
Purchases of property and equipment	(25,783)	(19,615)
Net cash flows used in investing activities	(23,904)	(18,076)
Cash flows from financing activities:
Borrowings under revolving lines of credit	121,745	9,242
Repayments under revolving lines of credit	(117,463)	(22,157)
Payment of principal obligations under equipment notes	(2,591)	(1,980)
Payment of principal obligations under finance leases	(275)	(302)
Proceeds from exercise of stock options	0	20
Payments related to tax withholding for stock-based compensation	(5,866)	(7,936)
Net cash flows used in financing activities	(4,450)	(23,113)
Effect of exchange rate changes on cash	(324)	30
Net decrease in cash and cash equivalents	(20,988)	(4,001)
Cash and cash equivalents:
Beginning of period	24,899	51,040
End of period	$ 3,911	$ 47,039