Balance Sheet Information-Warranty (Details 6) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning of period	$ 46,892,000	$ 48,742,000	$ 48,555,000	$ 43,624,000
Additions and adjustments to cost of revenue	3,229,000	1,746,000	10,806,000	14,104,000
Warranty liability assumed from acquisition	0	3,794,000	0	3,794,000
Usage	(4,352,000)	(6,794,000)	(13,592,000)	(14,034,000)
Balance, end of period	$ 45,769,000	$ 47,488,000	$ 45,769,000	$ 47,488,000