v3.21.1

Summary of Significant Accounting Policies; Prior Period Reclassification - Summary of Financial Assets and Liabilities Measured at Fair Value (Detail) - Recurring [Member] - Level 3 [Member] - Derivative Liability [Member] - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Feb. 01, 2020 | Jan. 30, 2021 | Dec. 31, 2019
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |  |
Balance, December 31, 2018 | $ 1,721 | $ 2,528 |
Initial recognition of conversion features and warrants |  |  | $ 7,954
Change in fair value of derivative liability | 807 | (543) | (6,233)
Derecognition of derivative liability upon debt conversion and cancellation of warrants |  | $ (1,985) |
Balance, December 31, 2019 | $ 2,528 |  | $ 1,721

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