Goodwill and Purchased Intangible Assets (Identified Intangible Assets) (Details) (USD $) In Millions	Apr. 29, 2011	Apr. 30, 2010
Net Assets	$ 53.0	$ 25.1
Identified Intangible Assets [Member]
Gross Assets	86.4	93.7
Accumulated Amortization	(33.4)	(68.6)
Net Assets	53.0	25.1
Customer Contracts/Relationships [Member]
Gross Assets	12.0	12.2
Accumulated Amortization	(4.6)	(8.8)
Net Assets	7.4	3.4
Covenants Not to Compete [Member]
Gross Assets	0.6	0
Accumulated Amortization	(0.1)	0
Net Assets	0.5	0
Existing Technology [Member]
Gross Assets	66.1	75.1
Accumulated Amortization	(23.2)	(55.5)
Net Assets	42.9	19.6
Trademarks and Tradenames [Member]
Gross Assets	7.7	6.4
Accumulated Amortization	(5.5)	(4.3)
Net Assets	$ 2.2	$ 2.1