Property And Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Property, Plant and Equipment, Net [Abstract]
Document Fiscal Year Focus	2016
Depreciation and amortization expense of property and equipment	$ 100.8	$ 101.3	$ 84.7