Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016
Deferred tax assets:
Reserves and accruals	$ 5,797	$ 11,043
Deferred revenue	240	349
Shared based compensation	1,483	2,590
Tax credit carry-forwards	9,669	10,112
Net operating losses	9,755	8,434
Depreciation & amortization	(1,525)	(2,898)
Other	207	(1,252)
Total deferred tax assets	25,626	28,378
Less: Valuation allowance	(13,702)	(10,980)
Total deferred tax assets net of valuation allowance	11,924	17,398
Deferred tax liabilities:
Depreciation & amortization	(12)	(6)
Other	(167)	(14)
Total deferred tax liabilities	(179)	(20)
Net deferred tax assets	$ 11,745	$ 17,378