Summary of Accrual Activities by Components Related to Company's Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 02, 2015	Sep. 26, 2014	Oct. 02, 2015	Sep. 26, 2014
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			$ 231
Restructuring charges	$ 1,051	$ 233	3,188	$ 73
Cash payments			(1,742)
Non-cash write-offs and other adjustments			(827)
Accrued expense ending balance	850		850
Severance
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			102
Restructuring charges			2,021
Cash payments			(1,438)
Non-cash write-offs and other adjustments			5
Accrued expense ending balance	690		690
Facility
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			105
Restructuring charges			139
Cash payments			(222)
Accrued expense ending balance	22		22
Depreciation
Restructuring Cost And Reserve [Line Items]
Restructuring charges			832
Non-cash write-offs and other adjustments			(832)
Other Restructuring Charges
Restructuring Cost And Reserve [Line Items]
Accrued expense beginning balance			24
Restructuring charges			196
Cash payments			(82)
Accrued expense ending balance	$ 138		$ 138