Trust Account and Fair Value Measurement (Details) - USD ($) |
9 Months Ended | 12 Months Ended | |
|---|---|---|---|
Sep. 30, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
|
| Assets: | |||
| Carrying value | $ 306,566,000 | $ 307,338,000 | |
| Gross Unrealized Holding Gains | 6,000 | ||
| Quoted Price Prices in Active Markets (Level 1) [Member] | |||
| Assets: | |||
| Carrying value | 307,344,000 | ||
| Cash and money market funds [Member] | |||
| Assets: | |||
| Carrying value | 306,566,000 | 11,000 | |
| Gross Unrealized Holding Gains | |||
| Cash and money market funds [Member] | Quoted Price Prices in Active Markets (Level 1) [Member] | |||
| Assets: | |||
| Carrying value | $ 306,566,000 | 11,000 | |
| U.S. government treasury bills [Member] | |||
| Assets: | |||
| Carrying value | 307,327,000 | ||
| Gross Unrealized Holding Gains | 6,000 | ||
| U.S. government treasury bills [Member] | Quoted Price Prices in Active Markets (Level 1) [Member] | |||
| Assets: | |||
| Carrying value | $ 307,333,000 |