Disposition of Business (Details) - USD ($)		3 Months Ended		9 Months Ended
	Apr. 07, 2015	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2016	Apr. 30, 2015
Disposition of Business
Proceeds from sale of business, net of cash retained and disposal costs					$ 3,942,000
Reclassification adjustment to loss on sale of business for foreign currency translation gain included in net income during the period			$ 1,264,000		1,264,000
Loss on sale of business			$ 2,206,000		$ 2,206,000
Diluted earnings per share (in dollars per share)		$ 0.34	$ 0.30	$ 1.05	$ 0.83
Specialty Packaging business | Other. | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Disposition of Business
Proceeds from sale of business, net of cash retained and disposal costs	$ 7,531,000
Amount held in escrow	$ 660,000
Loss on sale of business			$ 2,206,000
Diluted earnings per share (in dollars per share)			$ (0.04)