Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss), Net of Tax (Detail) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2020	Oct. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (66,477)	$ (71,254)
Other comprehensive income before reclassification	(3,484)	362
Amounts reclassified from accumulated other comprehensive loss	(293)	391
Ending balance	(69,668)
Unrealized (loss) gain on cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(200)	707
Other comprehensive income before reclassification	701	136
Amounts reclassified from accumulated other comprehensive loss	(159)	286
Ending balance	660	557
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(68,458)	(74,761)
Other comprehensive income before reclassification	(4,185)	226
Ending balance	(72,643)	(74,535)
Unamortized gain on post-retirement plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	2,181	2,800
Amounts reclassified from accumulated other comprehensive loss	(134)	105
Ending balance	$ 2,315	$ 2,695