Quarterly report pursuant to Section 13 or 15(d)

Goodwill and Intangible Assets, Net of Accumulated Amortization (Details Textual)

v2.4.0.6
Goodwill and Intangible Assets, Net of Accumulated Amortization (Details Textual) (USD $)
In Millions, unless otherwise specified
3 Months Ended 9 Months Ended
Feb. 28, 2013
Feb. 29, 2012
Feb. 28, 2013
Feb. 29, 2012
May 31, 2012
Goodwill and Intangible Assets, Net of Accumulated Amortization (Textual)          
Goodwill $ 533.9   $ 533.9   $ 517.4
Amortization expense relating to intangible assets $ 4.9 $ 5.8 $ 14.3 $ 17.2