Goodwill and Acquired Intangibles (Details) (USD $) In Thousands	9 Months Ended
	Oct. 01, 2011	Jan. 01, 2011
Changes in the carrying amount of goodwill
Balance as of January 1, 2011	$ 158,893
Goodwill resulting from the acquisition during the period (Note 4)	32,250
Additions due to contingent consideration (Note 4)	1,347
Effect of foreign currency translation	(337)
Balance as October 1, 2011	192,153
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross Carrying Amount	264,770	283,856
Accumulated amortization	84,725	105,158
Total acquired intangibles	180,045	178,698
Existing technology [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross Carrying Amount	90,453	91,800
Accumulated amortization	14,225	27,350
Total acquired intangibles	76,228	64,450
Agreements and relationships [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross Carrying Amount	118,034	135,773
Accumulated amortization	24,343	36,579
Total acquired intangibles	93,691	99,194
Distribution rights [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross Carrying Amount	30,100	30,100
Accumulated amortization	24,832	22,575
Total acquired intangibles	5,268	7,525
Tradenames trademarks and patents [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross Carrying Amount	26,183	26,183
Accumulated amortization	21,325	18,654
Total acquired intangibles	$ 4,858	$ 7,529