XML 26 R14.htm IDEA: XBRL DOCUMENT
v3.20.2

Stock Option Plans | 6 Months Ended
--- | ---
Jun. 30, 2020
Stock Option Plans |
Stock Option Plans | 8. Stock Option Plans ​ In February 2014, the Company adopted the 2014 Equity Incentive Plan (the “2014 Plan”), which was subsequently amended in November 2014, July 2015 and September 2015, under which it granted incentive stock options (“ISOs”) or non-qualified stock options (“NSOs”). Terms of stock agreements, including vesting requirements, are determined by the board of directors or a committee authorized by the board of directors, subject to the provisions of the 2014 Plan. In general, awards granted by the Company vest over four years and have a maximum exercise term of 10 years. The 2014 Plan provides that grants must be at an exercise price of 100% of fair market value of the Company’s common stock as determined by the board of directors on the date of the grant. ​ In connection with the consummation of the IPO in March 2016, the 2016 Equity Incentive Award Plan (the “2016 Plan”), became effective. Under the 2016 Plan, incentive stock options, non-statutory stock options, stock purchase rights and other stock-based awards may be granted. Terms of stock agreements, including vesting requirements, are determined by the board of directors or a committee authorized by the board of directors, subject to the provisions of the 2016 Plan. In general, awards granted by the Company vest over four years and have a maximum exercise term of 10 years. The 2016 Plan provides that grants must be at an exercise price of 100% of fair market value of the Company’s common stock as determined by the board of directors on the date of the grant. In conjunction with adopting the 2016 Plan, the 2014 Plan was terminated and no further awards will be granted under the 2014 Plan. Options outstanding under the 2014 Plan as of the effective date of the 2016 Plan that are forfeited or lapse unexercised may be re-issued under the 2016 Plan, up to a maximum of 1,136,229 shares. ​ Activity under the Company’s stock option plans is set forth below: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | Options Outstanding
​ |  | ​ |  | ​ |  | Weighted ‑
​ | ​ | Shares | ​ | ​ | ​ | Average
​ | ​ | Available | ​ | Number of | ​ | Exercise
​ |  | for Grant |  | Options |  | Price
Balance at December 31, 2019 |  | 1,704,183 |  | 5,643,410 | ​ | $ | 8.05
Additional shares authorized |  | 1,118,000 |  | — | ​ |  | —
Options granted |  | (190,000) |  | 190,000 | ​ |  | 2.68
Options exercised |  | — |  | (81,500) | ​ |  | 0.28
Options forfeited |  | 190,812 |  | (190,812) | ​ |  | 7.07
Balance at June 30, 2020 |  | 2,822,995 |  | 5,561,098 | ​ | $ | 8.01
​

X
- Definition The entire disclosure for share-based compensation plan details. + References No definition available. + Details
Name: | crvs_DisclosureOfShareBasedCompensationPlansTextBlock
Namespace Prefix: | crvs_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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