Note 15 - 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, 2019
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Open tax years	2016 2017 2018
State and Local Jurisdiction [Member]
Open tax years	2016 2017 2018
Foreign Tax Authority [Member] | Her Majesty's Revenue and Customs (HMRC) [Member]
Open tax years	2017 2018
Foreign Tax Authority [Member] | Ministry of the Economy, Finance and Industry, France [Member]
Open tax years	2016 2017 2018
Foreign Tax Authority [Member] | Federal Ministry of Finance, Germany [Member]
Open tax years	2016 2017 2018