Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2018	May 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 38,448	$ 17,252	$ 99,587	$ 28,243
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(414)	(694)	(2,006)	(1,488)
Pension obligations, net	174	266	30	281
Total other comprehensive loss, net of tax	(240)	(428)	(1,976)	(1,207)
Comprehensive income	38,208	16,824	97,611	27,036
Less comprehensive income attributable to noncontrolling interests	(1,046)	(687)	(2,806)	(1,967)
Comprehensive income attributable to SSI	$ 37,162	$ 16,137	$ 94,805	$ 25,069