Stockholders' Equity - Reconciliation of Retained Earnings (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Oct. 24, 2014	Oct. 25, 2013	Oct. 24, 2014	Oct. 25, 2013
Retained Earnings Adjustments [Line Items]
Beginning balance			$ 1.1
Net income	159.8	166.8	248.2	248.4
Repurchases of common stock			(195.9)
Dividends			(105.5)	(102.7)
Ending balance	0		0
Retained Earnings
Retained Earnings Adjustments [Line Items]
Dividends			$ (53.4)	$ (102.7)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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