Accumulated Other Comprehensive Items (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			$ 85,940
Foreign currency translation adjustment	$ (734)	$ (1,077)	(2,003)	$ (1,946)
Pension liability adjustments	353		750
Other comprehensive income (loss)	(391)	$ (1,074)	(1,253)	$ (1,915)
Balance	73,496		73,496
Foreign currency items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			6,131
Foreign currency translation adjustment			(2,003)
Other comprehensive income (loss)			(2,003)
Balance	4,128		4,128
Pension items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(4,206)
Pension liability adjustments			750
Other comprehensive income (loss)			750
Balance	(3,456)		(3,456)
Unrealized gains (losses) on Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			94
Balance	94		94
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			2,019
Balance	$ 766		$ 766