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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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-Topic 740

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The noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date.

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-Name Accounting Standards Codification

-Topic 210

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Oct. 24, 2014	Apr. 25, 2014	Oct. 25, 2013	Apr. 26, 2013
Income Tax Contingency [Line Items]
Resolution of income tax examinations	$ 47.4
Expected refund, excluding interest from fiscal 2005 to 2007 income tax audit	8.0
Gross unrecognized tax benefits	274.5	235.9	199.8	189.6
Unrecognized tax benefits included in other long-term liabilities	220.2
Unrecognized tax benefits that would affect provision for income taxes	168.2
United Kingdom's tax authority
Income Tax Contingency [Line Items]
Resolution of income tax examinations	$ (1.0)