Fair Value Measurements - Hierarchy Levels (Details) - Recurring basis - USD ($)	Jul. 31, 2016	Jul. 31, 2015
Assets:
Total assets	$ 740,000	$ 1,680,000
Liabilities:
Total accrued expenses	378,000	578,000
Total other long-term liabilities	1,201,000	2,199,000
Total liabilities	1,579,000	2,777,000
Accrued expenses
Liabilities:
Assumed contingent obligation	12,000	12,000
Contingent guaranteed obligation	366,000	566,000
Other long-term liabilities
Liabilities:
Contingent consideration		751,000
Assumed contingent obligation	1,126,000	1,126,000
Contingent guaranteed obligation	75,000	322,000
Money markets | Cash and cash equivalents
Assets:
Money markets	740,000	1,680,000
Level 1
Assets:
Total assets	740,000	1,680,000
Level 1 | Money markets | Cash and cash equivalents
Assets:
Money markets	740,000	1,680,000
Level 3
Liabilities:
Total accrued expenses	378,000	578,000
Total other long-term liabilities	1,201,000	2,199,000
Total liabilities	1,579,000	2,777,000
Level 3 | Accrued expenses
Liabilities:
Assumed contingent obligation	12,000	12,000
Contingent guaranteed obligation	366,000	566,000
Level 3 | Other long-term liabilities
Liabilities:
Contingent consideration		751,000
Assumed contingent obligation	1,126,000	1,126,000
Contingent guaranteed obligation	$ 75,000	$ 322,000