Warranty Reserves (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 01, 2012	Jul. 03, 2011	Jul. 01, 2012	Jul. 03, 2011
Warranty reserve activity
Balance beginning of period	$ 10,749	$ 8,271	$ 10,412	$ 8,250
Provision charged to income	4,271	3,731	8,897	7,059
Payments	(4,193)	(3,735)	(9,040)	(7,162)
Adjustments to previously provided warranties, net	30	682	487	557
Foreign currency translation and acquisitions	(232)	108	(131)	353
Balance end of period	$ 10,625	$ 9,057	$ 10,625	$ 9,057