Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2019	Oct. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (71,254)	$ (56,401)
Other comprehensive loss before reclassification	362	(9,640)
Amounts reclassified from accumulated other comprehensive loss	391	190
Ending balance	(71,283)
Unrealized gain on cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	707	863
Other comprehensive loss before reclassification	136	(491)
Amounts reclassified from accumulated other comprehensive loss	286	35
Ending balance	557	337
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(74,761)	(60,566)
Other comprehensive loss before reclassification	226	(9,149)
Ending balance	(74,535)	(69,715)
Unamortized gain on post-retirement plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	2,800	3,302
Amounts reclassified from accumulated other comprehensive loss	105	155
Ending balance	$ 2,695	$ 3,147