Changes in Accumulated Other Comprehensive (Loss) Income (Detail) $ in Thousands	9 Months Ended
	Apr. 30, 2017 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 531,177
Pre-tax change before reclassification to earnings	(2,100)
Amount reclassified to earnings	(200)
Income tax benefit (provision)	(100)
Ending balance	481,714
Unrealized Gain (Loss) on Foreign Currency Forward Contracts
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(200)
Amount reclassified to earnings	(200)
Income tax benefit (provision)	100
Ending balance	(300)
Unrealized Gains (Losses) on Pension Plan
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(4,900)
Pre-tax change before reclassification to earnings	200
Ending balance	(4,700)
Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(3,400)
Pre-tax change before reclassification to earnings	(2,300)
Income tax benefit (provision)	(200)
Ending balance	(5,900)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(8,500)
Ending balance	$ (10,900)