Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2016	Oct. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (54,745)	$ (45,034)
Other comprehensive income (loss) before reclassification	(12,280)	(7,330)
Amounts reclassified from accumulated other comprehensive loss	(111)	1,062
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax		0
Ending balance	(66,914)	(53,426)
Unrealized (loss) gain on cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(857)	9
Other comprehensive income (loss) before reclassification	328	60
Amounts reclassified from accumulated other comprehensive loss	(247)	279
Ending balance	(282)	(210)
Unamortized gain on post-retirement plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	2,236	3,438
Other comprehensive income (loss) before reclassification	0	0
Amounts reclassified from accumulated other comprehensive loss	136	783
Ending balance	2,100	2,655
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(56,124)	(48,481)
Other comprehensive income (loss) before reclassification	(12,608)	(7,390)
Amounts reclassified from accumulated other comprehensive loss	0
Ending balance	$ (68,732)	$ (55,871)