Segment Information - Reconciliation of Operating (Loss) Income from Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2020	May 31, 2019	May 31, 2020	May 31, 2019
Segment Reporting Information [Line Items]
Operating (loss) income	$ (3,706)	$ 24,459	$ (3,925)	$ 66,184
Restructuring charges and other exit-related activities	(2,710)	(75)	(7,810)	(813)
Interest expense	(2,656)	(2,294)	(5,399)	(6,267)
Other (expense) income, net	(90)	29	18	373
(Loss) income from continuing operations before income taxes	(6,452)	22,194	(9,306)	60,290
Continuing Operations
Segment Reporting Information [Line Items]
Restructuring charges and other exit-related activities	(2,710)	(75)	(7,810)	(813)
Interest expense	(2,656)	(2,294)	(5,399)	(6,267)
Other (expense) income, net	(90)	29	18	373
(Loss) income from continuing operations before income taxes	(6,452)	22,194	(9,306)	60,290
Continuing Operations | AMR
Segment Reporting Information [Line Items]
Operating (loss) income	2,503	29,189	19,375	73,947
Continuing Operations | CSS
Segment Reporting Information [Line Items]
Operating (loss) income	6,931	8,116	14,692	25,802
Continuing Operations | Operating Segments
Segment Reporting Information [Line Items]
Operating (loss) income	9,434	37,305	34,067	99,749
Continuing Operations | Corporate and eliminations
Segment Reporting Information [Line Items]
Operating (loss) income	$ (10,430)	$ (12,771)	$ (30,182)	$ (32,752)