CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Net income (loss)	$ 1,230	$ (481)	$ 4,159	$ (10,276)
Other comprehensive income (loss), before tax
Change in unrealized net gain on available-for-sale investments	5	(16)	8	41
Foreign currency translation gains (losses)	39	(17)	114	5
Other comprehensive income (loss), before tax	44	(33)	122	46
Income tax (expense) benefit related to items in other comprehensive income (loss)	0	0	0	0
Other comprehensive income (loss), net of tax	44	(33)	122	46
Comprehensive income (loss)	$ 1,274	$ (514)	$ 4,281	$ (10,230)