Acquired Intangible Assets and Goodwill (Details) (USD $) In Thousands, unless otherwise specified	Dec. 29, 2012	Dec. 31, 2011
Gross Carrying Amount	$ 33,498	$ 32,365
Accumulated Amortization	20,579	18,301
Patents [Member]
Gross Carrying Amount	23,306	22,369
Accumulated Amortization	15,487	13,372
Consulting Agreements [Member]
Gross Carrying Amount	976	976
Accumulated Amortization	976	976
Noncompete Agreements [Member]
Gross Carrying Amount	2,347	2,197
Accumulated Amortization	2,174	2,121
Customer Lists [Member]
Gross Carrying Amount	1,989	1,801
Accumulated Amortization	1,820	1,710
Trademarks [Member]
Gross Carrying Amount	4,880	5,022
Accumulated Amortization	$ 122	$ 122

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant