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Stock Based Compensation (Details) |  | 3 Months Ended | 88 Months Ended |
--- | --- | --- | --- | ---
Dec. 02, 2013 shares | Mar. 31, 2021 item shares | Mar. 31, 2020 shares | Mar. 31, 2021 shares | Jan. 01, 2021 shares
Employee stock options |  |  |  |  |
Stock-based compensation |  |  |  |  |
Options granted (in shares) |  | 1,321,917 | 1,137,420 |  |
ESPP |  |  |  |  |
Stock-based compensation |  |  |  |  |
Total number of shares of common stock available for issuance |  | 581,286 |  | 581,286 |
Awards issued under the plan (in shares) |  |  |  | 467,595 |
Increase in shares of common stock available for issuance (in shares) |  | 0 |  |  |
ESPP | Maximum |  |  |  |  |
Stock-based compensation |  |  |  |  |
Annual percentage increase in shares of common stock available for issuance |  | 1.00% |  |  |
Annual increase in shares of common stock available for issuance (in shares) |  | 621,814 |  |  |
Restricted stock units |  |  |  |  |
Stock-based compensation |  |  |  |  |
Awards issued under the plan (in shares) |  |  |  | 700,837 |
Granted |  | 247,050 |  |  |
Annual installment vesting periods | item |  | 3 |  |  |
The 2013 Plan |  |  |  |  |
Stock-based compensation |  |  |  |  |
Total number of shares of common stock available for issuance |  | 13,445,524 |  | 13,445,524 | 2,314,937
Annual percentage increase in shares of common stock available for issuance |  | 4.00% |  |  |
Awards issued under the plan (in shares) |  |  |  | 11,894,756 |
Increase in shares of common stock available for issuance (in shares) |  | 2,314,937 |  |  |
The 2010 Plan |  |  |  |  |
Stock-based compensation |  |  |  |  |
Total number of shares of common stock available for issuance |  | 2,684,456 |  | 2,684,456 |
Options granted (in shares) | 0 |  |  |  |

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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