Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Thousands	9 Months Ended
	May 31, 2016	May 31, 2015
Operating Activities
Cash provided by operating activities	$ 74,991	$ 43,624
Investing Activities
Capital expenditures	(15,623)	(17,234)
Proceeds from sale of property, plant and equipment	8,635	886
Business acquisitions, net of cash acquired	(80,674)	0
Intercompany Investment	0	0
Cash used in investing activities	(87,662)	(16,348)
Financing Activities
Purchase of treasury shares	(14,125)	(204,627)
Taxes paid related to the net share settlement of equity awards	(1,344)	(2,344)
Stock option exercises, related tax benefits and other	5,729	5,046
Payments of Debt Issuance Costs	0	(1,875)
Cash dividend	(2,376)	(2,598)
Intercompany Loan Activity	0	0
Intercompany Capital Contribution	0	0
Cash (used in) provided by financing activities	(12,326)	3,602
Effect of exchange rate changes on cash	(6,760)	(31,765)
Net decrease in cash and cash equivalents	(31,757)	(887)
Cash and cash equivalents – beginning of period	168,846	109,012
Cash and cash equivalents – end of period	137,089	108,125
Line of Credit | Senior Credit Facility - Revolver
Financing Activities
Net borrowings (repayment) on debt	(210)	0
Line of Credit | Senior Credit Facility - Term Loan
Financing Activities
Net borrowings (repayment) on debt	0	(3,375)
Proceeds from Long-term Lines of Credit	0	213,375
Parent
Operating Activities
Cash provided by operating activities	15,329	38,854
Investing Activities
Capital expenditures	(1,237)	(880)
Proceeds from sale of property, plant and equipment	13	0
Business acquisitions, net of cash acquired	0
Intercompany Investment	(339)	(1,117)
Cash used in investing activities	(1,563)	(1,997)
Financing Activities
Purchase of treasury shares	(14,125)	(204,627)
Taxes paid related to the net share settlement of equity awards	(1,344)	(2,344)
Stock option exercises, related tax benefits and other	5,729	5,046
Payments of Debt Issuance Costs		(1,875)
Cash dividend	(2,376)	(2,598)
Intercompany Loan Activity	12,139	58,569
Intercompany Capital Contribution	0	0
Cash (used in) provided by financing activities	(24,255)	(54,967)
Effect of exchange rate changes on cash	0	0
Net decrease in cash and cash equivalents	(10,489)	(18,110)
Cash and cash equivalents – beginning of period	18,688	27,931
Cash and cash equivalents – end of period	8,199	9,821
Parent | Line of Credit | Senior Credit Facility - Revolver
Financing Activities
Net borrowings (repayment) on debt	0
Parent | Line of Credit | Senior Credit Facility - Term Loan
Financing Activities
Net borrowings (repayment) on debt		(3,375)
Proceeds from Long-term Lines of Credit		213,375
Guarantors
Operating Activities
Cash provided by operating activities	5,017	(39,865)
Investing Activities
Capital expenditures	(3,091)	(3,495)
Proceeds from sale of property, plant and equipment	3,337	203
Business acquisitions, net of cash acquired	0
Intercompany Investment	(6,125)	0
Cash used in investing activities	(5,879)	(3,292)
Financing Activities
Purchase of treasury shares	0	0
Taxes paid related to the net share settlement of equity awards	0	0
Stock option exercises, related tax benefits and other	0	0
Payments of Debt Issuance Costs		0
Cash dividend	0	0
Intercompany Loan Activity	0	(40,796)
Intercompany Capital Contribution	339	0
Cash (used in) provided by financing activities	339	40,796
Effect of exchange rate changes on cash	0	0
Net decrease in cash and cash equivalents	(523)	(2,361)
Cash and cash equivalents – beginning of period	523	3,325
Cash and cash equivalents – end of period	0	964
Guarantors | Line of Credit | Senior Credit Facility - Revolver
Financing Activities
Net borrowings (repayment) on debt	0
Guarantors | Line of Credit | Senior Credit Facility - Term Loan
Financing Activities
Net borrowings (repayment) on debt		0
Proceeds from Long-term Lines of Credit		0
Non-Guarantors
Operating Activities
Cash provided by operating activities	54,645	44,635
Investing Activities
Capital expenditures	(11,295)	(12,859)
Proceeds from sale of property, plant and equipment	5,285	683
Business acquisitions, net of cash acquired	(80,674)
Intercompany Investment	0	0
Cash used in investing activities	(86,684)	(12,176)
Financing Activities
Purchase of treasury shares	0	0
Taxes paid related to the net share settlement of equity awards	0	0
Stock option exercises, related tax benefits and other	0	0
Payments of Debt Issuance Costs		0
Cash dividend	0	0
Intercompany Loan Activity	(12,139)	(17,773)
Intercompany Capital Contribution	6,125	1,117
Cash (used in) provided by financing activities	18,054	18,890
Effect of exchange rate changes on cash	(6,760)	(31,765)
Net decrease in cash and cash equivalents	(20,745)	19,584
Cash and cash equivalents – beginning of period	149,635	77,756
Cash and cash equivalents – end of period	128,890	97,340
Non-Guarantors | Line of Credit | Senior Credit Facility - Revolver
Financing Activities
Net borrowings (repayment) on debt	(210)
Non-Guarantors | Line of Credit | Senior Credit Facility - Term Loan
Financing Activities
Net borrowings (repayment) on debt		0
Proceeds from Long-term Lines of Credit		0
Eliminations
Operating Activities
Cash provided by operating activities	0	0
Investing Activities
Capital expenditures	0	0
Proceeds from sale of property, plant and equipment	0	0
Business acquisitions, net of cash acquired	0
Intercompany Investment	6,464	1,117
Cash used in investing activities	6,464	1,117
Financing Activities
Purchase of treasury shares	0	0
Taxes paid related to the net share settlement of equity awards	0	0
Stock option exercises, related tax benefits and other	0	0
Payments of Debt Issuance Costs		0
Cash dividend	0	0
Intercompany Loan Activity	0	0
Intercompany Capital Contribution	(6,464)	(1,117)
Cash (used in) provided by financing activities	(6,464)	(1,117)
Effect of exchange rate changes on cash	0	0
Net decrease in cash and cash equivalents	0	0
Cash and cash equivalents – beginning of period	0	0
Cash and cash equivalents – end of period	0	0
Eliminations | Line of Credit | Senior Credit Facility - Revolver
Financing Activities
Net borrowings (repayment) on debt	$ 0
Eliminations | Line of Credit | Senior Credit Facility - Term Loan
Financing Activities
Net borrowings (repayment) on debt		0
Proceeds from Long-term Lines of Credit		$ 0