Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2019	May 31, 2018	May 31, 2019	May 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 16,440	$ 38,448	$ 46,355	$ 99,587
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(1,838)	(414)	(2,570)	(2,006)
Pension obligations, net	142	174	384	30
Total other comprehensive loss, net of tax	(1,696)	(240)	(2,186)	(1,976)
Comprehensive income	14,744	38,208	44,169	97,611
Less comprehensive income attributable to noncontrolling interests	(750)	(1,046)	(1,585)	(2,806)
Comprehensive income attributable to SSI	$ 13,994	$ 37,162	$ 42,584	$ 94,805