Consolidated Income Statements (Unaudited) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Income Statements [Abstract]
REVENUES	$ 104,552,000	$ 93,392,000	$ 206,860,000	$ 184,895,000
Cost of revenues	78,940,000	70,153,000	155,704,000	137,853,000
Gross profit	25,612,000	23,239,000	51,156,000	47,042,000
General and administrative expenses	12,592,000	14,171,000	24,886,000	25,657,000
Income before income tax provision	13,020,000	9,068,000	26,270,000	21,385,000
Income tax provision	5,139,000	1,535,000	10,191,000	6,092,000
NET INCOME	$ 7,881,000	$ 7,533,000	$ 16,079,000	$ 15,293,000
Net income per common and common equivalent share
Basic	$ 0.68	$ 0.64	$ 1.39	$ 1.28
Diluted	$ 0.68	$ 0.62	$ 1.37	$ 1.26
Weighted average common and common equivalent
Basic	11,526,000	11,861,000	11,572,000	11,909,000
Diluted	11,672,000	12,104,000	11,729,000	12,145,000