Changes in Stockholders' Equity and Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 440,975
Net loss attributable to common stockholders for the six months ended July 4, 2015	$ (35,570)	$ 11,771	(88,917)	$ 23,755
Unrealized (loss) gain related to marketable securities, net of tax	17	(19)	(3)	(70)
Recognized loss on redemption of marketable securities, previously unrealized	(54)	108	234	99
Translation adjustments, net of tax	(49)	914	(55)	738
Common stock issued in connection with the exercise of stock options, ESPP and vested RSUs, net of tax			1,108
Stock repurchase			(6,970)
Retirement of treasury stock			0
Stock-based compensation expense related to stock options, ESPP and RSUs			8,363
Fair value of partially vested stock options and RSUs assumed in business acquisition			5,139
Defined benefit pension net actuarial losses			(156)
Noncontrolling Interest, Change in Redemption Value			296
Ending balance	359,422		359,422
Common stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			1,173
Common stock issued in connection with the exercise of stock options, ESPP and vested RSUs, net of tax			14
Retirement of treasury stock			(11)
Ending balance	1,176		1,176
Additional Paid-in capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			635,299
Common stock issued in connection with the exercise of stock options, ESPP and vested RSUs, net of tax			1,094
Retirement of treasury stock			(6,959)
Stock-based compensation expense related to stock options, ESPP and RSUs			8,363
Fair value of partially vested stock options and RSUs assumed in business acquisition			5,139
Noncontrolling Interest, Change in Redemption Value			296
Ending balance	642,640		642,640
Treasury stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			0
Stock repurchase			(6,970)
Retirement of treasury stock			6,970
Ending balance	0		0
Accumulated deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			(193,613)
Net loss attributable to common stockholders for the six months ended July 4, 2015			(88,917)
Defined benefit pension net actuarial losses			(1)
Noncontrolling Interest, Change in Redemption Value			0
Ending balance	(282,531)		(282,531)
Accumulated other comprehensive loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			(1,884)
Unrealized (loss) gain related to marketable securities, net of tax			(3)
Recognized loss on redemption of marketable securities, previously unrealized			234
Translation adjustments, net of tax			(55)
Defined benefit pension net actuarial losses	2	$ 0	(155)	$ 0
Noncontrolling Interest, Change in Redemption Value			0
Ending balance	$ (1,863)		$ (1,863)