Fair Value of Financial Instruments - 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 | 9 Months Ended | 12 Months Ended |
|---|---|---|---|
Feb. 01, 2020 |
Oct. 31, 2020 |
Dec. 31, 2019 |
|
| Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] | |||
| Beginning Balance | $ 1,721 | $ 2,527 | |
| Initial recognition of conversion features and warrants, October 2019 | $ 7,954 | ||
| Change in fair value of derivative liability | 806 | (543) | (6,233) |
| Extinguishment of derivative liability resulting from debt conversion | $ (1,984) | ||
| Ending Balance | $ 2,527 | $ 1,721 |