Investments and Fair Value of Financial Assets and Liabilities (Tables)
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12 Months Ended |
Dec. 31, 2018 |
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| Investments and Fair Value of Financial Assets and Liabilities |
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| Schedule of investments by security type |
Investments by security type consisted of the following (in thousands):
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December 31, 2018
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Gross
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Gross
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Unrealized
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Unrealized
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Amortized Cost
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Gains
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Losses
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Fair Value
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U.S. treasury notes (due within one year)
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$
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79,312
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$
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—
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$
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(26)
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$
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79,286
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U.S. government agency bonds (due within one year)
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17,704
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—
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(3)
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17,701
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$
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97,016
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$
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—
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$
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(29)
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$
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96,987
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| Schedule of financial assets and liabilities measured at fair value on a recurring basis |
The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands):
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Fair value measurements at December 31, 2018 using:
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Level 1
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Level 2
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Level 3
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Total
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Assets:
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Cash equivalents:
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Money market funds
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$
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282,160
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$
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—
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$
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—
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$
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282,160
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U.S. treasury bills
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—
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24,904
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—
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24,904
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Marketable securities:
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U.S. government agency bonds
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—
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17,701
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—
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17,701
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U.S. treasury notes
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—
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79,286
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—
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79,286
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$
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282,160
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$
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121,891
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$
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—
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$
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404,051
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Fair value measurements at December 31, 2017 using:
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Level 1
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Level 2
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Level 3
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Total
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Assets:
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Cash equivalents:
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Money market funds
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$
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104,288
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$
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—
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$
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—
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$
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104,288
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Liabilities:
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Preferred stock warrant liability
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$
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—
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$
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—
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$
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866
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$
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866
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| Roll-forward of aggregate fair values of preferred stock warrants for which fair value determined by Level 3 inputs |
The following table provides a roll-forward of the aggregate fair values of the Company’s preferred stock warrants for which fair value was determined by Level 3 inputs (in thousands):
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Preferred stock
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warrant liability
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Fair value at December 31, 2016
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$
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67
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Issuance of warrants to purchase shares of Series B convertible preferred stock
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14
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Change in fair value
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785
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Fair value at December 31, 2017
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866
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Change in fair value through the exercise date
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2,187
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Reclassification to additional paid-in capital in connection with IPO
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(3,053)
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Fair value at December 31, 2018
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$
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—
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