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Stock-Based Awards (Details) - shares |  | 9 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 01, 2024 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023 | Sep. 30, 2015
Stock-based awards |  |  |  |  |
Options outstanding |  | 6,445,232 |  | 6,419,455 |
Stock Option Valuation |  |  |  |  |
Risk-free interest rate (as a percent) |  | 3.85% | 3.53% |  |
Expected term (in years) |  | 6 years | 6 years 2 months 12 days |  |
Expected volatility (as a percent) |  | 81.95% | 77.73% |  |
Expected dividend yield (as a percent) |  | 0.00% | 0.00% |  |
2017 Inducement Plan |  |  |  |  |
Stock-based awards |  |  |  |  |
Options outstanding |  | 329,000 |  |  |
2015 Equity Incentive Plan |  |  |  |  |
Stock-based awards |  |  |  |  |
Number of shares authorized |  |  |  |  | 1,643,872
Number of shares available for grant |  | 4,440,792 |  |  |
Percentage increase to shares available for grant from common outstanding as of preceding December 31 (as a percent) |  | 4.00% |  |  |
Additional shares available | 2,835,795 |  |  |  |
Options outstanding |  | 5,778,988 |  |  |
2015 Equity Incentive Plan | Restricted stock unit awards |  |  |  |  |
Stock-based awards |  |  |  |  |
Number of shares outstanding |  | 3,071,776 |  |  |
2012 Equity Compensation Plan |  |  |  |  |
Stock-based awards |  |  |  |  |
Number of shares available for grant |  | 0 |  |  |
Options outstanding |  | 337,244 |  |  |

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- Definition The percentage of increase to the number of shares available for grant from the common stock outstanding as of the end of the preceding calendar year. + References No definition available. + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition Number of additional shares authorized for issuance under share-based payment arrangement. + References No definition available. + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + 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://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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