Fair Value Measurements (Details 2) (Recurring basis, USD $)	Apr. 30, 2015	Jul. 31, 2014
Level 1
Assets:
Total assets	$ 1,680,000	$ 1,702,000
Level 1 | Money markets | Cash and cash equivalents
Assets:
Money markets	1,680,000	1,702,000
Level 2
Liabilities:
Total accrued expenses	14,000	69,000
Total liabilities	14,000	69,000
Level 2 | Interest rate swap agreements | Accrued expenses
Liabilities:
Interest rate swap agreement	14,000	69,000
Level 3
Liabilities:
Total accrued expenses	613,000	684,000
Total other long-term liabilities	1,432,000	2,463,000
Total liabilities	2,774,000	5,869,000
Level 3 | Accrued expenses
Liabilities:
Assumed contingent obligation	12,000
Contingent consideration	601,000	684,000
Level 3 | Contingent consideration
Liabilities:
Contingent consideration	729,000	2,722,000
Level 3 | Other long-term liabilities
Liabilities:
Assumed contingent obligation	1,119,000	1,752,000
Contingent consideration	313,000	711,000
Total
Assets:
Total assets	1,680,000	1,702,000
Liabilities:
Total accrued expenses	627,000	753,000
Total other long-term liabilities	1,432,000	2,463,000
Total liabilities	2,788,000	5,938,000
Total | Accrued expenses
Liabilities:
Assumed contingent obligation	12,000
Contingent consideration	601,000	684,000
Total | Contingent consideration
Liabilities:
Contingent consideration	729,000	2,722,000
Total | Other long-term liabilities
Liabilities:
Assumed contingent obligation	1,119,000	1,752,000
Contingent consideration	313,000	711,000
Total | Interest rate swap agreements | Accrued expenses
Liabilities:
Interest rate swap agreement	14,000	69,000
Total | Money markets | Cash and cash equivalents
Assets:
Money markets	$ 1,680,000	$ 1,702,000