Fair Value Measurements (Details 2) (USD $)	Jul. 31, 2013	Jul. 31, 2012
Interest rate swap agreements
Additional disclosures
Current portions of derivative liabilities	$ 133,000	$ 212,000
Long-term portions of derivative liabilities	29,000	123,000
Recurring basis | Level 1
Assets:
Money markets	4,241,000	3,916,000
Total assets	4,241,000	3,916,000
Recurring basis | Level 2
Other liabilities:
Interest rate swap agreements	162,000	335,000
Total other liabilities	162,000	335,000
Total liabilities	162,000	335,000
Recurring basis | Level 3
Acquisitions payable:
Contingent consideration		1,500,000
Price floor	45,000	1,037,000
Total acquisitions payable	45,000	2,537,000
Other liabilities:
Total liabilities	45,000	2,537,000
Recurring basis | Total
Assets:
Money markets	4,241,000	3,916,000
Total assets	4,241,000	3,916,000
Acquisitions payable:
Contingent consideration		1,500,000
Price floor	45,000	1,037,000
Total acquisitions payable	45,000	2,537,000
Other liabilities:
Interest rate swap agreements	162,000	335,000
Total other liabilities	162,000	335,000
Total liabilities	$ 207,000	$ 2,872,000