| Stock-based Compensation - Summary of Increase in Maximum Number of Shares Issuable to Stockholders (Details) - 2014 Equity Incentive Plan - shares | 1 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
| Dec. 31, 2017 | Jun. 30, 2017 | Dec. 31, 2019 | Dec. 31, 2015 | Dec. 31, 2014 | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Original share pool (in shares) | 2,058,000 | ||||
| Increase (in shares) | 4,400,000 | 1,000,000 | 3,500,000 | 1,656,000 | |
| Total share authorized for grant (in shares) | 12,614,000 | ||||
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- Definition Aggregate number of common shares reserved for future issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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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. No definition available. 
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- Definition Number of additional shares authorized for issuance under share-based payment arrangement. No definition available. 
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- Definition Number of shares authorized for issuance under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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