Taxes (Details) - Schedule of earnings from continuing operations before income taxes (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2012
Taxes (Details) - Schedule of earnings from continuing operations before income taxes [Line Items]
Earnings (loss) from continuing operations before income taxes	$ 50.4	$ 53.4	$ 169.7
United States
Taxes (Details) - Schedule of earnings from continuing operations before income taxes [Line Items]
Earnings (loss) from continuing operations before income taxes	43.5	34.6	145.4
Non-United States
Taxes (Details) - Schedule of earnings from continuing operations before income taxes [Line Items]
Earnings (loss) from continuing operations before income taxes	$ 6.9	$ 18.8	$ 24.3