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Information Concerning Product Lines, Geographic Information and Revenue Concentration - Schedule of Revenue by Shipment Destination (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 2,158	$ 3,510	$ 7,439	$ 9,396
Asia Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	528	1,737	2,496	4,030
North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	1,518	1,370	3,747	4,409
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	112	403	1,196	957
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 510	$ 842	$ 1,300	$ 1,200
Japan \| Total Revenue
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue	24.00%	24.00%	17.00%	13.00%
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue				$ 1,400
China \| Total Revenue
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue				15.00%
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 1,400	$ 1,400	$ 3,600	$ 4,300
United States \| Total Revenue
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue	67.00%	39.00%	49.00%	46.00%