Stock-Based Compensation (Performance-Contingent Total Shareholder Return Shares) - Additional Information (Detail)	4 Months Ended
	Apr. 25, 2015	Apr. 19, 2014	Apr. 20, 2013
Total Shareholder Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of actual ROI attainment	88.00%
2012 awards | Total Shareholder Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of actual ROI attainment	195.00%
Performance Contingent Total Shareholder Return Shares | Performance contingent Awards 2013, 2014 and 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years	2 years	2 years
Performance Contingent Total Shareholder Return Shares | Performance contingent Awards 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	18 months
Total Shareholders Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, fair value assumptions, method used	Inputs into the model included the following for the company and comparator companies (i) TSR from the beginning of the performance cycle through the measurement date; (ii) volatility; (iii) risk-free interest rates; and (iv) the correlation of the comparator companies' TSR. The inputs are based on historical capital market data.