Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Aug. 31, 2016	Aug. 31, 2015	May 31, 2015	May 31, 2016
Operating income from discontinued operations
Operating loss from discontinued operations	$ (0.6)	$ (3.7)
Telair Cargo Group and PSM | Discontinued Operations, Held-for-sale or Disposed of by Sale
Discontinued Operations
General corporate overhead	0.0
Assets and liabilities held for sale related to discontinued operations
Assets of discontinued operations	0.9			$ 4.0
Liabilities of discontinued operations	9.3			12.5
Operating income from discontinued operations
Sales	0.6	2.5
Cost of sales	(1.0)	(5.3)
Selling, general and administrative expenses	(0.2)	(0.9)
Operating loss from discontinued operations	$ (0.6)	(3.7)
Telair Cargo Group | Disposed of by sale
Discontinued Operations
Cash consideration received before fees and expenses			$ 705.0
Gain on sale of assets			198.6
Telair Cargo Group | A400M | Disposed of by sale
Discontinued Operations
Gain recognized on sale of business		$ 27.7
Telair Cargo Group | A400M | Maximum | Disposed of by sale
Discontinued Operations
Contingent consideration			$ 35.0
Precision Systems Manufacturing | Discontinued Operations, Held-for-sale
Discontinued Operations
Recognized impairment charge				$ 57.5