Stock-Based Compensation, SARs (Details) (Stock Appreciation Rights (SARs), USD $)	6 Months Ended
	Oct. 25, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vesting each year from date of grant	25.00%
Period from grant date for first vesting	1 year
Vesting period	4 years
Awards Granted During 2014
Fair value assumptions
Risk-free interest rate (as a percent)	1.05%
Dividend rate (as a percent)	1.10%
Expected life in years	3 years 7 months 17 days
Stock price volatility (as a percent)	43.20%
Fair value per share (in dollars per share)	$ 7.67
Awards Granted During 2013
Fair value assumptions
Risk-free interest rate (as a percent)	1.05%
Dividend rate (as a percent)	1.10%
Expected life in years	2 years 8 months 16 days
Stock price volatility (as a percent)	35.22%
Fair value per share (in dollars per share)	$ 10.25