Segment Information (Tables)

12 Months Ended

Dec. 31, 2017

Segment Information [Abstract]

Summary of net revenues by geographic region

	2017
	Amount		Percentage
United States	$	4,187		41	%
Japan		2,800		27	%
Germany		1,188		12	%
China		737		7	%
Sweden		515		5	%
Taiwan		268		3	%
South Korea		176		2	%
Singapore		147		1	%
Canada		89		1	%
Other		134		1	%
Total	$	10,241		100	%

	2016
	Amount		Percentage
United States	$	5,374		53	%
China		1,365		13	%
Sweden		1,105		11	%
Germany		822		8	%
Japan		755		7	%
Canada		432		4	%
Taiwan		228		2	%
South Korea		71		1	%
Other		61		1	%
Total	$	10,213		100	%

	2015
	Amount		Percentage
United States	$	5,687		51	%
Sweden		2,372		21	%
Japan		905		8	%
China		600		5	%
Canada		489		4	%
Germany		390		4	%
Taiwan		312		3	%
South Korea		133		1	%
Other		227		3	%
Total	$	11,115		100	%