Balance Sheet Components (Tables)

6 Months Ended

Jun. 30, 2017

Balance Sheet Related Disclosures [Abstract]

Schedule of Property and Equipment

Property and equipment consisted of the following (in thousands):

	June 30, 2017			December 31, 2016
Prototype	$	11,929		$	6,405
Machinery and equipment		6,739			6,057
Leasehold improvements		4,371			4,371
Software		1,050			1,028
Furniture and fixtures		450			368
Construction in progress		—			5,498
Property and equipment, gross		24,539			23,727
Less: accumulated depreciation and amortization		(13,151	)		(12,167	)
Property and equipment, net	$	11,388		$	11,560

Summary of Intangible Assets

Intangible assets consisted of the following (in thousands):

	June 30, 2017			December 31, 2016
License cost	$	512		$	512
Patents		104			104
Intangible assets, gross		616			616
Accumulated amortization		(529	)		(519	)
Intangible assets, net	$	87		$	97

Summary of Estimated Future Amortization Expense

At June 30, 2017, the estimated future amortization expense of intangible assets was as follows (in thousands):

Year Ending December 31,	EstimatedFuture Amortization Expense
The remainder of 2017	$	10
2018		19
2019		19
2020		19
2021		10
2022		3
Thereafter		7
Total amortization expense	$	87

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):

	June 30, 2017		December 31, 2016
Accrued payroll and related benefits	$	3,387	$	4,274
Accrued accounts payable		2,860		1,202
Accrued legal, accounting and governance fees		483		509
Sales tax payable		53		13
Other		703		336
Total accrued liabilities	$	7,486	$	6,334

Schedule of Deferred Revenue

Deferred revenue consisted of the following (in thousands):

	June 30, 2017			December 31, 2016
Deferred revenue:
Product	$	11,950		$	5,050
Services		1,834			1,561
Distribution rights		3,585			3,822
Total deferred revenue		17,369			10,433
Less: current portion of deferred revenue		(13,787	)		(6,515	)
Noncurrent portion of deferred revenue	$	3,582		$	3,918