Summary of Accrual Activities by Components Related to Company's Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2015	Jun. 27, 2014	Jul. 03, 2015	Jun. 27, 2014
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			$ 231
Restructuring charges	$ 384	$ (188)	2,137	$ (160)
Cash payments			(1,090)
Non-cash write-offs and other adjustments			(577)
Accrued expense ending balance	701		701
Severance
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			102
Restructuring charges			1,343
Cash payments			(881)
Non-cash write-offs and other adjustments			5
Accrued expense ending balance	569		569
Facility
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			105
Restructuring charges			99
Cash payments			(176)
Accrued expense ending balance	28		28
Depreciation
Restructuring Cost And Reserve [Line Items]
Restructuring charges			582
Non-cash write-offs and other adjustments			(582)
Other Restructuring Charges
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			24
Restructuring charges			113
Cash payments			(33)
Accrued expense ending balance	$ 104		$ 104