Other Accrued Liabilities (Details) (USD $)	3 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Jul. 31, 2013
Other Accrued Liabilities [Abstract]
Allowance for project disallowances	$ 2,670,851	$ 2,723,974
Other	1,515,864		1,406,722
Total other accrued liabilities	4,186,715		4,070,073
Allowance for Project Disallowances [Roll Forward]
Balance at beginning of period	2,663,351	2,724,474
Net change due to government audits during the period, recorded as a transfer of reserves (to) from allowance for doubtful accounts and contract adjustments	7,500	(500)
Balance at end of period	$ 2,670,851	$ 2,723,974