COMPREHENSIVE INCOME (LOSS) - Accumulated Other Comprehensive Income Items (Detail) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2019	Oct. 31, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 52,692	$ 107,628
Foreign currency translation adjustment	13	(1,622)
Pension liability adjustments	(2)	405
Other comprehensive income (loss)	11	(1,232)
Ending balance	57,137	105,431
Foreign currency items
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	5,017
Foreign currency translation adjustment	13
Pension liability adjustments	0
Other comprehensive income (loss)	13
Ending balance	5,030
Pension items
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(4,079)
Foreign currency translation adjustment	0
Pension liability adjustments	(2)
Other comprehensive income (loss)	(2)
Ending balance	(4,081)
Unrealized gains (losses) on securities
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	96
Foreign currency translation adjustment	0
Pension liability adjustments	0
Other comprehensive income (loss)	0
Ending balance	96
Accumulated Other Comprehensive Income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,034	2,734
Other comprehensive income (loss)	11	(1,232)
Ending balance	$ 1,045	$ 1,502