XML 26 R15.htm IDEA: XBRL DOCUMENT
v3.21.2

Equity Incentive Plans | 6 Months Ended
--- | ---
Jun. 30, 2021
Share-based Payment Arrangement [Abstract] |
Equity Incentive Plans | EQUITY INCENTIVE PLANS Stock-Based Compensation Stock-based compensation expense recognized for stock options, restricted stock units ("RSUs"), performance-based restricted stock units ("PRSUs") and our employee stock purchase program (the "ESPP") are recorded as operating expenses in our condensed statements of operations and comprehensive loss, as follows (in thousands):
| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2021 |  | 2020 |  | 2021 |  | 2020
Research and development | $ | 1,087 |  |  | $ | 1,144 |  |  | $ | 2,179 |  |  | $ | 2,202 |
General and administrative | 2,132 |  |  | 1,530 |  |  | 4,127 |  |  | 3,420 |
Total | $ | 3,219 |  |  | $ | 2,674 |  |  | $ | 6,306 |  |  | $ | 5,622 |
As of June 30, 2021, our total unrecognized stock-based compensation expense, net of estimated forfeitures, and average remaining vesting period, included the following (dollars in thousands):
| Unrecognized Compensation Expense |  | Average Remaining Vesting Period (Years)
Stock options | $ | 25,267 |  |  | 2.8
RSUs | $ | 6,978 |  |  | 3.6
ESPP | $ | 151 |  |  | 0.2
Stock Options A summary of our stock option activity and related information for the six months ended June 30, 2021 is as follows (in thousands, except dollar amounts):
| Number of Shares |  | Weighted Average Exercise Price
Outstanding balance at December 31, 2020 | 9,790 |  |  | $ | 6.76 |
Granted | 3,328 |  |  | $ | 6.62 |
Exercised | (205) |  |  | $ | 2.75 |
Forfeited | (401) |  |  | $ | 7.56 |
Outstanding balance at June 30, 2021 | 12,511 |  |  | $ | 6.76 |
Exercisable at June 30, 2021 | 6,043 |  |  | $ | 7.38 |
Restricted Stock Units A summary of our RSUs activity and related information for the six months ended June 30, 2021 is as follows (in thousands, except dollar amounts):
| Number of RSUs |  | Weighted Average Value at Grant
Outstanding balance at December 31, 2020 | 159 |  |  | $ | 5.64 |
Granted | 1,088 |  |  | $ | 6.62 |
Vested | (80) |  |  | $ | 6.43 |
Forfeited | (32) |  |  | $ | 6.10 |
Unvested at June 30, 2021 | 1,135 |  |  | $ | 6.52 |
We issued no PRSUs during the six months ended June 30, 2021 and we have no PRSUs outstanding as of June 30, 2021. Employee Stock Purchase Plan In February 2021, we sold approximately 0.2 million shares of our common stock under the ESPP. The shares were purchased by employees at a purchase price of $5.84 per share resulting in proceeds to us of approximately $1.4 million. Issuance of Common Stock for Services Under Our Amended and Restated Non-Employee Director Compensation Program, members of our board of directors may elect to receive shares of our stock in lieu of their cash fees. During the six months ended June 30, 2021, we issued no shares of our common stock to members of the board of directors in accordance with the program.

X
- Definition The entire disclosure for share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -URI http://asc.fasb.org/topic&trid=2228938 + Details
Name: | us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration