Acquisitions and Purchase Accounting - Danfotech Acquisition (Details) (USD $) In Thousands, unless otherwise specified	Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011	Dec. 31, 2011 Danfotech [Member]	Jul. 05, 2011 Danfotech [Member]	Jul. 05, 2011 Danfotech [Member] as initially reported [Member]	Jul. 05, 2011 Danfotech [Member] Measurement Period Adjustments [Member]
Business Acquisition [Line Items]
Cash					$ 165	$ 165	$ 0
Deferred tax asset					235	0	235
Current assets					703	1,073	(370)
Property, plant and equipment					47	102	(55)
Goodwill	526,011	477,812	369,989		5,678	3,423	2,255
Other intangibles					1,086	1,864	(778)
Other assets					4	4	0
Current liabilities					1,116	309	807
Long-term deferred tax liability					(137)	(46)	(91)
Other non-current liabilities					(750)	0	(750)
Consideration paid at closing					5,915	6,276	(361)
Additional assets acquired post closing				700	730	0	730
Contingent consideration					1,500	1,500	0
Net assets acquired and liabilities assumed					$ 8,145	$ 7,776	$ 369