Consolidated Statements of Income - USD ($)	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Revenues	$ 718,562,000	$ 646,230,000	$ 552,644,000
Cost of revenues	560,303,000	494,116,000	429,020,000
Gross profit	158,259,000	152,114,000	123,624,000
General and administrative	73,705,000	67,602,000	64,449,000
Income before income taxes	84,554,000	84,512,000	59,175,000
Income tax provision	18,189,000	18,102,000	12,819,000
Net income	$ 66,365,000	$ 66,410,000	$ 46,356,000
Net income per share:
Basic	$ 3.83	$ 3.74	$ 2.59
Diluted	$ 3.77	$ 3.66	$ 2.55
Weighted average shares outstanding:
Basic	17,328,000	17,753,000	17,930,000
Diluted	17,592,000	18,127,000	18,166,000