CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 29, 2023	Jul. 30, 2022	Jul. 29, 2023	Jul. 30, 2022
Income Statement [Abstract]
Contract revenues	$ 1,041,535	$ 972,273	$ 2,087,009	$ 1,848,573
Costs of earned revenues, excluding depreciation and amortization	830,409	797,980	1,683,775	1,543,710
General and administrative	84,832	73,336	167,188	142,716
Depreciation and amortization	37,993	35,345	75,265	71,981
Total	953,234	906,661	1,926,228	1,758,407
Interest expense, net	(12,277)	(9,347)	(23,649)	(18,465)
Other income, net	5,731	2,587	10,722	7,381
Income before income taxes	81,755	58,852	147,854	79,082
Provision for income taxes	21,509	14,996	36,085	15,690
Net income	$ 60,246	$ 43,856	$ 111,769	$ 63,392
Earnings per common share:
Basic earnings per common share (in dollars per share)	$ 2.05	$ 1.48	$ 3.81	$ 2.14
Diluted earnings per common share (in dollars per share)	$ 2.03	$ 1.46	$ 3.76	$ 2.11
Shares used in computing earnings per common share:
Basic (in shares)	29,328,218	29,540,174	29,348,700	29,579,498
Diluted (in shares)	29,610,946	29,943,422	29,708,025	30,021,486