Restructuring and Related Charges - Liability Activity, Primarily Associated with 2017 Restructuring Plan (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Restructuring Reserve [Roll Forward]
Liability, Beginning Balance			$ 21,337
Restructuring and related charges	$ 817	$ 5,427	6,842	$ 16,815
Asset write-off charge and other non-cash activity			2,965
Cash payments			(19,267)
Liability, Ending Balance	11,877		11,877
Employee severance and benefit costs
Restructuring Reserve [Roll Forward]
Liability, Beginning Balance			18,131
Restructuring and related charges	3,768	2,012	8,947	5,989
Asset write-off charge and other non-cash activity			(240)
Cash payments			(17,804)
Liability, Ending Balance	9,034		9,034
Lease costs
Restructuring Reserve [Roll Forward]
Liability, Beginning Balance			2,684
Restructuring and related charges	0	7	9	7
Asset write-off charge and other non-cash activity			0
Cash payments			(303)
Liability, Ending Balance	2,390		2,390
Asset write-off costs
Restructuring Reserve [Roll Forward]
Liability, Beginning Balance			0
Restructuring and related charges	(3,396)	$ 2,451	(3,212)	$ 9,263
Asset write-off charge and other non-cash activity			3,212
Cash payments			0
Liability, Ending Balance	0		0
Other Related Costs
Restructuring Reserve [Roll Forward]
Liability, Beginning Balance			522
Restructuring and related charges			1,098
Asset write-off charge and other non-cash activity			(7)
Cash payments			(1,160)
Liability, Ending Balance	$ 453		$ 453