Note 17 - Other Equity Matters (Details Textual) $ in Millions	9 Months Ended
Feb. 28, 2017 USD ($)
Dividends Related to Sentilus LLC Spin-Off [Member]
Payments of Dividends	$ 7.3
Dividends Related to Stock Redemption and Tax Payments to be made by Holdings [Member]
Payments of Dividends	$ 0.4

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

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