Consolidated Income Statements - Unaudited - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
REVENUES	$ 146,082,000	$ 140,734,000	$ 444,656,000	$ 414,777,000
Cost of revenues	116,728,000	115,165,000	352,459,000	334,675,000
Gross profit	29,354,000	25,569,000	92,197,000	80,102,000
General and administrative expenses	15,803,000	15,496,000	46,834,000	43,794,000
Income before income tax provision	13,551,000	10,073,000	45,363,000	36,308,000
Income tax provision	3,253,000	504,000	10,498,000	9,571,000
NET INCOME	$ 10,298,000	$ 9,569,000	$ 34,865,000	$ 26,737,000
Net income per common and common equivalent share
Basic	$ 0.55	$ 0.51	$ 1.85	$ 1.42
Diluted	$ 0.54	$ 0.50	$ 1.83	$ 1.41
Weighted average common and common equivalent shares
Basic	18,758,000	18,849,000	18,852,000	18,806,000
Diluted	18,984,000	19,121,000	19,058,000	19,029,000