Share Repurchases (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2016	May 31, 2015	May 31, 2016	May 31, 2015	Jul. 22, 2015	Jan. 03, 2014
Repurchase authorization increase amount					$ 100.0
Shares repurchased	219,578	371,886	688,790	977,812
Aggregate purchase price of shares repurchased	$ 16.1	$ 29.1	$ 48.3	$ 78.5
Remaining amount available under the repurchase program	$ 63.7		$ 63.7
Maximum [Member]
Repurchase authorization amount						$ 150.0