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Stock Option Plans - Stock Option Activity (Details) - $ / shares | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 | Feb. 28, 2014 | Dec. 31, 2016
Shares Available for Grant |  |  |
Beginning balance |  |  | 2,559,499
Ending balance |  |  | 2,475,600
Number of Options |  |  |
Beginning balance |  |  | 784,136
Ending balance |  |  | 2,350,582
2016 Plan |  |  |
Stock Option Plans |  |  |
Vesting period | 4 years |  |
Maximum exercise term | 10 years |  |
Exercise price of common stock of its fair value (as a percent) | 100.00% |  |
Shares Available for Grant |  |  |
Beginning balance |  |  | 2,559,499
Shares authorized for plan |  |  | 1,496,001
Granted |  |  | (1,813,400)
Forfeited |  |  | 233,500
Ending balance |  |  | 2,475,600
Number of Options |  |  |
Beginning balance |  |  | 784,136
Granted |  |  | 1,813,400
Exercised |  |  | (13,454)
Forfeited |  |  | (233,500)
Ending balance |  |  | 2,350,582
Weighted Average Exercise Price |  |  |
Beginning balance (in dollars per share) |  |  | $ 4.09
Granted (in dollars per share) |  |  | 15.09
Exercised (in dollars per share) |  |  | 0.28
Forfeited (in dollars per share) |  |  | 11.35
Ending balance (in dollars per share) |  |  | $ 11.88
2014 Plan |  |  |
Stock Option Plans |  |  |
Vesting period |  | 4 years |
Maximum exercise term |  | 10 years |
Exercise price of common stock of its fair value (as a percent) |  | 100.00% |
Maximum number of options that may be re-issued under the 2016 plan | 1,136,229 |  |

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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Number of additional shares authorized for issuance under an established share-based compensation plan. + References No definition available. + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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