Consolidated Statements Of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
Apr. 27, 2012	Apr. 29, 2011	Apr. 30, 2010
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 605.4	$ 673.1	$ 400.4
Other comprehensive income:
Foreign currency translation adjustments	(6.7)	10.4	1.5
Defined benefit obligation adjustments	(4.4)	0	0
Unrealized holding gains arising during the period	1.5	5.3	6.4
Income tax effect on unrealized holding gains	0.5	(2.1)	0
Reclassification adjustments for gains included in net income	(0.5)	(0.7)	(1.1)
Unrealized holding gains (losses) arising during the period	20.6	3.2	(0.5)
Reclassification adjustments for losses (gains) included in net income	(18.9)	(6.1)	1.7
Other comprehensive income (loss)	(7.9)	10.0	8.0
Comprehensive income	$ 597.5	$ 683.1	$ 408.4

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