Fair Value Measurements - Summary of Changes in Estimated Fair Value of Redeemable Convertible Preferred Stock Warrant Liability (Details) - USD ($) $ in Thousands |
9 Months Ended | |
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Sep. 30, 2018 |
Sep. 30, 2017 |
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| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
| Proceeds from issuances of common stock upon exercise of warrants | $ (2) | $ 0 |
| Redeemable Convertible Preferred Stock Warrant Liability | ||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
| Balance as of December 31, 2017 | 1,708 | |
| Proceeds from issuances of common stock upon exercise of warrants | (2) | |
| Changes in estimated fair value of warrant liability included in other income (expense), net | (839) | |
| Balance as of September 30, 2018 | $ 867 | |
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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 Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties. No definition available.
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- Definition Fair value of financial and nonfinancial obligations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cash inflow associated with the amount received from holders exercising their stock warrants. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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