Summary of Significant Accounting Policies (Details) - USD ($)	3 Months Ended		9 Months Ended
	May 31, 2017	May 31, 2016	May 31, 2017	May 31, 2016	Aug. 31, 2016	Feb. 01, 2016
Significant Accounting Policies [Line Items]
Book Overdrafts	$ 4,000,000		$ 4,000,000		$ 3,000,000
Assets Held-for-sale	0		0		1,000,000
Cost Method Investments, Original Cost	6,000,000		6,000,000
Goodwill	166,273,000		166,273,000		166,847,000
Goodwill impairment charge	0	$ 0	0	$ 8,845,000
Cash, FDIC Insured Amount	250,000		250,000
Customer Issued Letters Of Credit	47,000,000		47,000,000		$ 40,000,000
Regionally Defined Reporting Unit Consisting of Two Components
Significant Accounting Policies [Line Items]
Goodwill						$ 9,000,000
Regionally Defined Reporting Unit Consisting Of One Component
Significant Accounting Policies [Line Items]
Goodwill						$ 166,000,000
Goodwill | Income Approach Valuation Technique | Regionally Defined Reporting Unit Consisting Of One Component
Significant Accounting Policies [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount						27.00%
Other Asset Impairment Charge (Recoveries), Net
Significant Accounting Policies [Line Items]
Impairment of Assets Held-for-sale				2,000,000
Gain (Loss) on Disposition of Assets	$ 1,000,000
Asset Impairment, Investment in Joint Venture				$ 2,000,000
Corporate Joint Venture
Significant Accounting Policies [Line Items]
Joint Venture, Gain (Loss) on Disposition of Assets			6,000,000
Gain (Loss) on Disposition of Assets from Joint Venture			$ 3,000,000