Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 29, 2012	Dec. 31, 2011
Summary of Finite-lived intangible assets
Adjusted cost	$ 31,497	$ 31,581
Accumulated amortization	(20,517)	(17,187)
Net carrying amount	10,980	14,394
Developed technology [Member]
Summary of Finite-lived intangible assets
Adjusted cost	17,700	17,489
Accumulated amortization	(8,277)	(5,600)
Net carrying amount	9,423	11,889
Customer relationships [Member]
Summary of Finite-lived intangible assets
Adjusted cost	9,538	9,517
Accumulated amortization	(8,643)	(8,164)
Net carrying amount	895	1,353
Brand names [Member]
Summary of Finite-lived intangible assets
Adjusted cost	1,927	1,927
Accumulated amortization	(1,599)	(1,499)
Net carrying amount	328	428
Patented technology [Member]
Summary of Finite-lived intangible assets
Adjusted cost	2,252	2,252
Accumulated amortization	(1,922)	(1,856)
Net carrying amount	330	396
In-process research and development [Member]
Summary of Finite-lived intangible assets
Adjusted cost		316
Accumulated amortization		0
Net carrying amount		316
Trademark [Member]
Summary of Finite-lived intangible assets
Adjusted cost	80	80
Accumulated amortization	(76)	(68)
Net carrying amount	$ 4	$ 12