Cost Reduction Actions Wind-Down of Microsatellite Product Line (Details) - USD ($)	12 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Restructuring Reserve [Roll Forward]
Restructuring reserve, current	$ 908,000
Wind-Down of Microsatellite Product Line [Member]
Restructuring Reserve [Roll Forward]
Pre-tax restructuring charge (benefit)	0	$ (56,000)	$ 458,000
Restructuring reserve, current	$ 147,000