Stock Benefit Plans and Equity Transactions (Tables)

3 Months Ended

Mar. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Total Stock Based Compensation

Total stock-based compensation for the three months ended March 31, 2019 and 2018 is as follows (in thousands):

	Three Months Ended
	March 31,
	2019		2018
Cost of revenues	$	28	$	22
Research and development		462		(116	)
Sales, general and administrative		1,122		713
Total	$	1,612	$	619

Summary of Common Stock Reserved for Future Issuance

As of March 31, 2019, the Company had reserved shares of its common stock for future issuance as follows (in thousands):

	March 31, 2019
Stock options outstanding		4,670
Unvested restricted stock award		3,761
Employee stock purchase plan		223
Series A convertible preferred stock		164
Warrants outstanding		22,302
Distributor and Development Services plans		3,985
Authorized for future grant under the Company equity plans		461
Total		35,566

Summary of Outstanding Warrants

A summary of all outstanding warrants is as follows:

	Number of Warrants		Strike Price
2017 Common Stock Warrants		3,757,000	$	2.00
2017 Banker Warrants		167,418	$	2.50
2018 Common Stock Warrants		13,996,851	$	3.50
Merger Warrants		2,200,000	$	3.50
Executive		1,327,434	$	5.00
Squadron Capital		845,000	$	3.15
Other		7,812	$	19.20
Total		22,301,515