UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Contract revenues	$ 815,562	$ 811,616
Contract costs	729,319	727,224
Gross profit	86,243	84,392
Selling, general and administrative expenses	62,233	56,964
Amortization of intangible assets	1,228	1,226
Gain on sale of property and equipment	(1,489)	(1,224)
Income from operations	24,271	27,426
Other income (expense):
Interest income	142	321
Interest expense	(1,054)	(586)
Other expense, net	(263)	(90)
Income before provision for income taxes	23,096	27,071
Income tax expense	4,157	3,908
Net income	$ 18,939	$ 23,163
Income per common share:
Basic (in dollars per share)	$ 1.13	$ 1.39
Diluted (in dollars per share)	$ 1.12	$ 1.38
Weighted average number of common shares and potential common shares outstanding:
Basic (in shares)	16,711	16,618
Diluted (in shares)	16,837	16,824
Net income	$ 18,939	$ 23,163
Other comprehensive income (loss):
Foreign currency translation adjustment	(2,472)	136
Other comprehensive income (loss)	(2,472)	136
Total comprehensive income	$ 16,467	$ 23,299