Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2019	Jan. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (56,401)	$ (44,682)
Other comprehensive loss (income) before reclassification	(3,650)	9,737
Amounts reclassified from accumulated other comprehensive loss	514	(145)
Ending balance	(60,565)	(35,090)
Unrealized gain on cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	863	109
Other comprehensive loss (income) before reclassification	47	(598)
Amounts reclassified from accumulated other comprehensive loss	215	(126)
Ending balance	695	(363)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(60,566)	(47,411)
Other comprehensive loss (income) before reclassification	(3,528)	9,953
Amounts reclassified from accumulated other comprehensive loss	0	0
Ending balance	(64,094)	(37,458)
Unamortized gain on post-retirement plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	3,302	2,620
Other comprehensive loss (income) before reclassification	(169)	382
Amounts reclassified from accumulated other comprehensive loss	299	271
Ending balance	$ 2,834	$ 2,731