Employees' Stock Incentive Plans and Management Incentive Plans 1 (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
Apr. 28, 2013	Apr. 29, 2012	Apr. 27, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	7 years	5 years	5 years 6 months
Excess tax benefits reported as operating cash inflow	$ 8.1	$ 7.5	$ 12.4
Excess tax benefits reported as financing cash inflow	10.3	7.6	8.6
Stock Option Awards Granted Fiscal 2004 Through 2006 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Expected term (years)	10 years
Stock Option Awards Granted Fiscal 2006 Through Current [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Expected term (years)	7 years
Stock Option and Restricted Stock Plans [Member] \| Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	33.7	36.5	32.7
Tax benefit from compensation cost related to Employees' Stock Incentive Plans and Management Incentive Plans	10.8	12.0	10.4
Allocated Share-based Compensation Expense, Net of Tax	$ 22.9	$ 24.5	$ 22.3
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	9,440	9,400
Fiscal Year 2003 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	18,869	18,900

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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-Publisher FASB

-Name Accounting Standards Codification

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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No definition available.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of excess tax benefit (tax deficiency) that arises when compensation cost from non-qualified share-based compensation recognized on the entity's tax return exceeds (is less than) compensation cost from equity-based compensation recognized in financial statements. Excess tax benefit (tax deficiency) increases (decreases) net cash provided by financing activities.

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Amount of excess tax benefit (tax deficiency) that arises when compensation cost from non-qualified equity-based compensation recognized on the entity's tax return exceeds (is less than) compensation cost from equity-based compensation recognized in financial statements. Excess tax benefit (tax deficiency) reduces (increases) net cash provided by operating activities.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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