Segment Information (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2013	Apr. 30, 2012
Revenues :
Total	$ 68,250	$ 56,995	$ 203,739	$ 164,472
Entity-wide revenue attributable to other country	0	0	0	0
EntityWideRevenueMajorCountryPercentage	10.00%	10.00%	10.00%	10.00%
United States [Member]
Revenues :
Total	37,751	29,727	109,961	93,008
Canada [Member]
Revenues :
Total	10,620	12,572	31,685	25,547
Australia [Member]
Revenues :
Total	3,141	3,435	10,613	13,552
United Kingdom [Member]
Revenues :
Total	5,035	4,734	17,114	11,570
Other [Member]
Revenues :
Total	$ 11,703	$ 6,527	$ 34,366	$ 20,795