Summary of Significant Accounting Policies - Reconciliation of Changes in Warranty Liability (Details) - USD ($) $ in Thousands	6 Months Ended
	Jul. 04, 2015		Jun. 28, 2014
Reconciliation of the changes in the Company's warranty liability
Balance, beginning of period	$ 469	[1]	$ 468
Accruals for product warranties	183		134
Cost of warranty claims and adjustments	(132)		(96)
Balance, end of period	$ 520		$ 506

[1] Derived from the audited consolidated financial statements included in the Annual Report on Form 10-K filed with the SEC for the year ended January 3, 2015.