Income Tax Matters (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Deferred tax assets [Abstract]
Accounts receivable	$ 192	$ 204
Inventories	1,111	1,002
Accrued liabilities	201	173
Deferred revenue	4,879	5,456
Other	465	172
Loss on foreign subsidiaries	2,370	1,720
Valuation allowance	(2,370)	(1,720)
Deferred tax assets	6,848	7,007
Deferred tax liability [Abstract]
Property and equipment	986	960
Other intangible assets	4,292	2,786
Deferred tax liability	5,278	3,746
Deferred tax assets (liability), net	1,570	3,261
Deferred tax amounts classified on consolidated balance sheets [Abstract]
Current assets	$ 2,346	2,042
Long-term asset		1,219
Long-term liability	$ (776)	0
Deferred tax assets (liability), net	1,570	3,261
Provision for income taxes [Abstract]
Current (receivable) payable	1,447	(338)	$ 1,179
Deferred	94	1,836	(49)
Provision for income taxes	$ 1,541	$ 1,498	$ 1,130
Reconciliation of income tax at statutory rate to effective rate [Abstract]
Computed at the statutory rate (in hundredths)	34.00%	34.00%	34.00%
State taxes, net of federal tax benefit (in hundredths)	1.80%	2.40%	2.50%
Foreign rate differential (in hundredths)	(4.20%)	(3.20%)	0.00%
Production deduction for domestic manufacturers (in hundredths)	(2.70%)	(2.00%)	(4.30%)
State tax settlement (in hundredths)	(3.70%)	0.00%	0.00%
Research and experimentation (in hundredths)	(1.70%)	(1.60%)	(5.30%)
Other (in hundredths)	2.10%	3.20%	3.70%
Effective income tax rate (in hundredths)	25.60%	32.80%	30.60%