Fair Value Measurement - Warrants (Details) - Warrant - USD ($) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
|
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||
| Fair value, liability, beginning balance | $ 16,335,000 | $ 1,822,819 |
| Exercise of warrants | (28,511,690) | 0 |
| Change in fair value | 12,176,690 | 15,369,253 |
| Reclassification to additional paid-in capital | 0 | (857,072) |
| Fair value, liability, ending balance | $ 0 | $ 16,335,000 |