Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	Nov. 30, 2017	Aug. 31, 2017
Impaired Assets [Line Items]
Goodwill	$ 531,454	$ 530,081
Future Amortization Expense, Remainder of 2018	15,300
Future Amortization Expense, 2019	19,900
Future Amortization Expense, 2020	19,200
Future Amortization Expense, 2021	18,300
Future Amortization Expense, 2022	16,300
Future Amortization Expense, 2023	13,300
Future Amortization Expense, Thereafter	$ 21,900