Accounting Policies (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 30, 2011	Dec. 31, 2010	Jan. 01, 2010
Accounting Policies [Line Items]
Estimated useful lives goodwill and purchased intangible assets, minimum, in years	1
Estimated useful lives of goodwill and purchased intangible assets, maximum, in years	10
Weighted average useful life of goodwill and purchased intangible assets, in years	6.5
Advertising expense	$ 23,700,000	$ 21,300,000	$ 20,400,000
Third party funding for research and development costs	7,800,000	11,700,000	12,500,000
Depreciation expense	$ 20,509,000	$ 18,198,000	$ 18,795,000
Maturity period of derivative financial instrument, minimum, in months	one
Maturity period of derivative financial instrument, maximum, in months	three
Machinery And Equipment [Member]
Accounting Policies [Line Items]
Useful life of asset, minimum, in years	2
Useful life of asset, maximum, in years	6
Furniture And Fixtures [Member]
Accounting Policies [Line Items]
Average useful life of asset, in years	5
Computer Equipment And Software [Member]
Accounting Policies [Line Items]
Useful life of asset, minimum, in years	2
Useful life of asset, maximum, in years	5
Building [Member]
Accounting Policies [Line Items]
Average useful life of asset, in years	40
Internal-Use Of Software [Member]
Accounting Policies [Line Items]
Useful life of asset, minimum, in years	3
Useful life of asset, maximum, in years	5
Minimum [Member]
Accounting Policies [Line Items]
Warranty periods for products sold, in days	90
Maximum [Member]
Accounting Policies [Line Items]
Warranty periods for products sold, in years	5.5