Income Taxes - Tax Effect of Temporary Differences and Carryforwards that Give Rise to Significant Portions of the Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Jan. 02, 2016
Tax effect of temporary differences and carryforwards that give rise to significant portions of the net deferred tax assets
Net operating losses	$ 4,411	$ 4,135
Research and development credits	2,113	1,820
Accruals and reserves	2,158	1,823
Deferred revenue	104	120
Property and equipment	396	399
Intangible assets	783	792
Stock compensation	972	613
Other tax credits	90	89
Net deferred tax asset	11,027	9,791
Valuation allowance	(11,095)	(806)
Net deferred tax assets		$ 8,985
Net deferred tax (liabilities)	$ (68)