CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	12 Months Ended
Apr. 24, 2015	Apr. 25, 2014	Apr. 26, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 559.9us-gaap_NetIncomeLoss	$ 637.5us-gaap_NetIncomeLoss	$ 505.3us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Foreign currency translation adjustments	(28.3)	3.5	(2.9)
Defined benefit obligations:
Defined benefit obligation adjustments	(11.8)	0.7	(3.9)
Reclassification adjustments related to defined benefit obligations	0.3	0.6	0
Income tax effect on defined benefit obligations	3.9	(0.4)	2.6
Unrealized gains (losses) on available-for-sale securities:
Unrealized holding gains (losses) arising during the period	2.0	(2.5)	7.3
Reclassification adjustments for gains included in net income	(0.3)	(1.3)	(0.6)
Income tax effect on unrealized holding (gains) losses	0.3	1.3	(0.2)
Unrealized gains (losses) on cash flow hedges:
Unrealized holding gains (losses) arising during the period	15.5	(3.5)	3.7
Reclassification adjustments for (gains) losses included in net income	(14.4)	2.0	(2.2)
Other comprehensive income (loss)	(32.8)	0.4	3.8
Comprehensive income	$ 527.1us-gaap_ComprehensiveIncomeNetOfTax	$ 637.9us-gaap_ComprehensiveIncomeNetOfTax	$ 509.1us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax and reclassification adjustments of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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