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 | |