Stockholders' Equity (Narrative) (Details) - USD ($) shares in Millions	3 Months Ended	6 Months Ended
	Oct. 02, 2016	Oct. 02, 2016	Oct. 31, 2015	Apr. 30, 2015
Class of Stock [Line Items]
Number of shares repurchased (shares)	1.2	2.7
Cost of shares repurchased	$ 23,800,000	$ 54,400,000
Amount available for future purchase	$ 131,300,000	$ 131,300,000
April 2015 Stock Repurchase Program
Class of Stock [Line Items]
Authorized amount				$ 300,000,000
October 2015 Stock Repurchase Program
Class of Stock [Line Items]
Additional authorized repurchase amount			$ 300,000,000