Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, Beginning Balance	$ (44,682)	$ (54,745)
Other comprehensive income (loss) before reclassification	(13,395)	10,250
Amounts reclassified from accumulated other comprehensive loss	193	187
Accumulated other comprehensive (loss) income, Ending Balance	(56,401)	(44,682)	$ (54,745)
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	1,869	0	0
Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, Beginning Balance	109	(857)
Other comprehensive income (loss) before reclassification	465	670
Amounts reclassified from accumulated other comprehensive loss	383	(296)
Accumulated other comprehensive (loss) income, Ending Balance	863	109	(857)
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	(94)
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, Beginning Balance	(47,411)	(56,124)
Other comprehensive income (loss) before reclassification	(14,242)	8,713
Amounts reclassified from accumulated other comprehensive loss	0	0
Accumulated other comprehensive (loss) income, Ending Balance	(60,566)	(47,411)	(56,124)
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	1,087
Other Postretirement Benefit Plan, Defined Benefit [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, Beginning Balance	2,620	2,236
Other comprehensive income (loss) before reclassification	382	867
Amounts reclassified from accumulated other comprehensive loss	(576)	483
Accumulated other comprehensive (loss) income, Ending Balance	3,302	$ 2,620	$ 2,236
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	$ 876