Income Taxes (Details 3) (USD $) In Thousands, unless otherwise specified	Jan. 03, 2015	Dec. 28, 2013
Tax effect of temporary differences and carryforwards that give rise to significant portions of the net deferred tax assets
Accruals and reserves	$ 1,681	$ 1,792
Deferred revenue	113us-gaap_DeferredTaxAssetsDeferredIncome	91us-gaap_DeferredTaxAssetsDeferredIncome
Fixed assets	439	423
Intangibles	825	441
Stock compensation	676	696
Net operating loss	4,278	5,224
Research and development credits	1,575	1,260
Other tax credits	94	47
Net deferred tax asset	9,681us-gaap_DeferredTaxAssetsGross	9,974us-gaap_DeferredTaxAssetsGross
Valuation allowance	(905)	(9,974)
Net deferred tax assets	$ 8,776us-gaap_DeferredTaxAssetsNet

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