Stockholders' Equity - Reclassification from AOCI to Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jul. 01, 2016	Jun. 30, 2017	Jul. 01, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	$ 0	$ (22)	$ 0	$ (100)
Cost of Sales [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	0	(3)	0	(13)
Operating Expense [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	$ 0	$ (19)	$ 0	$ (87)