Summary of Significant Accounting Policies - Reconciliation of Changes in Deferred Revenue (Details) - USD ($) $ in Thousands	6 Months Ended
	Jul. 04, 2015		Jun. 28, 2014
Reconciliation of the changes in the Company's deferred revenue balance
Balance, beginning of period	$ 1,179	[1]	$ 1,133
Additions to deferral	687		636
Revenue recognized	(667)		(686)
Balance, end of period	$ 1,199		$ 1,083

[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.