Restructuring (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2014 Position	Jan. 31, 2013	Apr. 30, 2013
Restructuring (Textual) [Abstract]
Percent of estimated position reductions incurred-to-date due to restructuring plan	90.00%		90.00%
Total expected restructuring charge			$ 265.0
Restructuring costs incurred announcement-to-date			244.7
Reduction in positions due to restructuring			850
Total restructuring charges	5.1	5.4	17.1	30.1	38.8
Cost of products sold restructuring	$ 1.6	$ 0.8	$ 5.1	$ 6.4