Accumulated Other Comprehensive Loss Schedule of Accumulated Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (71,254)	$ (56,401)
Other comprehensive loss (income) before reclassification	(661)	(3,650)
Amounts reclassified from accumulated other comprehensive loss	(575)	(514)
Ending balance	(72,490)
Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	707	863
Other comprehensive loss (income) before reclassification	468	47
Amounts reclassified from accumulated other comprehensive loss	(365)	(215)
Ending balance	810	695
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(74,761)	(60,566)
Other comprehensive loss (income) before reclassification	(913)	(3,528)
Amounts reclassified from accumulated other comprehensive loss	0	0
Ending balance	(75,674)	(64,094)
Unamortized gain on post-retirement plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	2,800	3,302
Other comprehensive loss (income) before reclassification	(216)	(169)
Amounts reclassified from accumulated other comprehensive loss	(210)	(299)
Ending balance	$ 2,374	2,834
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance		$ (60,565)