Note 16 - Income Taxes - Major Tax Jurisdictions in Which the Company and Affiliates Operate and the Earliest Tax Year Subject to Examination (Details)	9 Months Ended
	May 31, 2017
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Earliest Tax Year [Member]
Open tax years	2014
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Latest Tax Year [Member]
Open tax years	2017
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Open tax years	2010
State and Local Jurisdiction [Member] | Latest Tax Year [Member]
Open tax years	2017
Foreign Tax Authority [Member] | Ministry of the Economy, Finance and Industry, France [Member] | Earliest Tax Year [Member]
Open tax years	2013
Foreign Tax Authority [Member] | Ministry of the Economy, Finance and Industry, France [Member] | Latest Tax Year [Member]
Open tax years	2017
Foreign Tax Authority [Member] | Her Majesty's Revenue and Customs (HMRC) [Member] | Earliest Tax Year [Member]
Open tax years	2012
Foreign Tax Authority [Member] | Her Majesty's Revenue and Customs (HMRC) [Member] | Latest Tax Year [Member]
Open tax years	2017