Accumulated Other Comprehensive Income Items (Detail) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2018	Oct. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 107,628	$ 62,971
Foreign currency translation adjustment	(1,622)	272
Net unrealized holding gain on securities	(15)	(13)
Pension liability adjustments	405	26
Other comprehensive income (loss)	(1,232)	285
Balance	105,431	58,314
Foreign currency items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	6,348
Foreign currency translation adjustment	(1,622)
Other comprehensive income (loss)	(1,622)
Balance	4,726
Pension items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(3,795)
Pension liability adjustments	405
Other comprehensive income (loss)	405
Balance	(3,390)
Unrealized gains (losses) on Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	181
Net unrealized holding gain on securities	(15)
Other comprehensive income (loss)	(15)
Balance	166
Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	2,734	4,313
Other comprehensive income (loss)	(1,232)	285
Balance	$ 1,502	$ 4,598