Subsequent Events (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Oct. 31, 2012	Nov. 05, 2012	Nov. 02, 2012
Subsequent Events (Textual) [Abstract]
Cash paid by company		$ 26.9
Shares issued	0.5
Value of transaction			32.7
Additional amount received			$ 11.0

Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

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+ Details