Restructuring (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013 Position	Oct. 31, 2012	Apr. 30, 2013
Restructuring (Textual) [Abstract]
Percent of estimated position reductions incurred-to-date due to restructuring plan	80.00%		80.00%
Total expected restructuring charge			$ 260.0
Restructuring costs incurred announcement-to-date			239.6
Reduction in positions due to restructuring			850
Total restructuring charges	6.8	10.3	12.0	24.8	38.8
Cost of products sold restructuring	$ 2.1	$ 2.0	$ 3.5	$ 5.6