Condensed Consolidated Statements Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
Condensed Consolidated Statements Of Income [Abstract]
Revenues	$ 200,964	$ 175,252	$ 370,285	$ 327,090
Cost of revenues	177,866	155,484	329,094	291,620
Gross profit	23,098	19,768	41,191	35,470
Selling, general and administrative expenses	11,898	11,136	23,381	21,725
Operating income	11,200	8,632	17,810	13,745
Other income (expense):
Interest expense	(166)	(197)	(443)	(367)
Interest income	3	9	6	22
Other	301	83	(375)	110
Income before income tax expense	11,338	8,527	16,998	13,510
Provision for federal, state and foreign income taxes	4,307	3,240	6,458	5,134
Net income	$ 7,031	$ 5,287	$ 10,540	$ 8,376
Basic earnings per common share	$ 0.27	$ 0.20	$ 0.40	$ 0.32
Diluted earnings per common share	$ 0.27	$ 0.20	$ 0.40	$ 0.32
Weighted average common shares outstanding:
Basic	25,819	26,400	26,110	26,372
Diluted	26,111	26,628	26,420	26,584