Consolidated Income Statements - Unaudited - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
REVENUES	$ 128,219,000	$ 124,460,000	$ 256,678,000	$ 251,399,000
Cost of revenues	102,307,000	97,776,000	205,184,000	198,532,000
Gross profit	25,912,000	26,684,000	51,494,000	52,867,000
General and administrative expenses	14,644,000	13,209,000	28,105,000	28,171,000
Income before income tax provision	11,268,000	13,475,000	23,389,000	24,696,000
Income tax provision	4,316,000	5,208,000	8,946,000	9,529,000
NET INCOME	$ 6,952,000	$ 8,267,000	$ 14,443,000	$ 15,167,000
Net income per common and common equivalent share
Basic	$ 0.36	$ 0.42	$ 0.74	$ 0.76
Diluted	$ 0.35	$ 0.41	$ 0.73	$ 0.75
Weighted average common and common equivalent shares
Basic	19,581,000	19,902,000	19,577,000	20,026,000
Diluted	19,733,000	20,063,000	19,743,000	20,199,000