Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2018

Accounting Policies [Abstract]

Summary of Estimated Lives of Assets

Depreciation is recorded using the straight-line method over the estimated useful lives of the assets as follows:

Machinery, manufacturing and demonstration equipment	3-5 years
Computer equipment	3 years
Furniture	5 years
Leasehold improvements	Lesserof lease term or 3 to 10 years

Summary of Revenue Disaggregated by Types and Geography

The following table presents revenue disaggregated by types and geography:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
	(in thousands)				(in thousands)
	(unaudited)				(unaudited)
U.S.
Systems	$	868	$	—	$	1,742	$	—
Instruments and accessories		426		—		835		—
Services		87		—		137		—
Total U.S. revenue		1,381		—		2,714		—
Outside of U.S. ("OUS")
Systems		3,450		—		10,686		2,609
Instruments and accessories		441		10		2,653		683
Services		150		173		525		421
Total OUS revenue		4,041		183		13,864		3,713
Total
Systems		4,318		—		12,428		2,609
Instruments and accessories		867		10		3,488		683
Services		237		173		662		421
Total revenue	$	5,422	$	183	$	16,578	$	3,713