Other Income (Expense), net (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Other Income and Expenses [Abstract]
Interest income	$ 180	$ 107	$ 488	$ 266
Interest expense	(11)	(3)	(35)	(5)
(Loss) Gain on foreign exchange	(131)	508	(620)	1,660
Other expense, net	0	0	(1)	0
Total other income (expense), net	$ 38	$ 612	$ (168)	$ 1,921

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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