Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended											12 Months Ended
	Jun. 30, 2013		Mar. 31, 2013	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012		Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2011
Quarterly Financial Information Disclosure [Abstract]
Sales Revenue, Services, Net	$ 235,560	[1]	$ 225,970	$ 221,436	[2]	$ 209,608	$ 184,862	[1]	$ 183,899	$ 200,964	$ 169,321	$ 892,574	$ 739,046	$ 627,052
Gross Profit	26,999	[1]	23,126	22,333	[2]	22,244	18,656	[1]	19,771	23,098	18,093	94,702	79,618	74,914
Operating Income (Loss)	11,587	[1]	8,431	8,772	[2]	7,924	6,410	[1]	7,415	11,200	6,610	36,714	31,635	30,900
Net Income (Loss) Attributable to Parent	$ 7,367	[1]	$ 6,521	$ 5,436	[2]	$ 4,684	$ 1,786	[1]	$ 4,862	$ 7,031	$ 3,509	$ 24,008	$ 17,188	$ 18,982
Basic earnings per common share	$ 0.28	[1]	$ 0.25	$ 0.21	[2]	$ 0.18	$ 0.07	[1]	$ 0.19	$ 0.27	$ 0.13	$ 0.92	$ 0.66	$ 0.72
Diluted earnings per common share	$ 0.28	[1]	$ 0.25	$ 0.21	[2]	$ 0.18	$ 0.07	[1]	$ 0.19	$ 0.27	$ 0.13	$ 0.91	$ 0.65	$ 0.71

[1] The fourth quarter of fiscal 2013 includes a pretax charge on a Canadian project of $0.6 million. The fourth quarter of fiscal 2012 included an income tax charge of $3.1 million. The income tax charge represents adjustments of $2.1 million for prior fiscal years and $1.0 million in fiscal 2012, of which $0.2 million related to fourth quarter activity.

[2] The second quarter of fiscal 2013 includes a pretax charge on a Canadian project of $3.3 million