Consolidated Income Statements - Unaudited - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
REVENUES	$ 148,092,000	$ 146,082,000	$ 445,200,000	$ 444,656,000
Cost of revenues	118,839,000	116,728,000	350,024,000	352,459,000
Gross profit	29,253,000	29,354,000	95,176,000	92,197,000
General and administrative expenses	17,000,000	15,803,000	49,290,000	46,834,000
Income before income tax provision	12,253,000	13,551,000	45,886,000	45,363,000
Income tax provision	2,901,000	3,253,000	10,256,000	10,498,000
NET INCOME	$ 9,352,000	$ 10,298,000	$ 35,630,000	$ 34,865,000
Net income per common and common equivalent share
Basic	$ 0.51	$ 0.55	$ 1.94	$ 1.85
Diluted	$ 0.50	$ 0.54	$ 1.91	$ 1.83
Weighted average common and common equivalent shares
Basic	18,253,000	18,758,000	18,410,000	18,852,000
Diluted	18,526,000	18,984,000	18,695,000	19,058,000