v3.19.3.a.u2

Fair Value Disclosure - Schedule of Level 3 Instruments (Details) - Convertible Preferred Stock Warrant Liability $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Convertible preferred stock warrant liability — beginning balance | $ 9,990 |
Fair value of new warrants issued | 2,032 |
Change in fair value of preferred stock warrant liability | 40,333 | [1]
Reclassification to additional paid in capital upon conversion to common warrants | $ (52,355) |
[1] | Recognized in the consolidated statements of operations within other income (expense), net.

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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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