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v3.21.1

Fair Value Measurements - Financial assets that are measured at fair value on a recurring basis (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2020
Liabilities: |  |  |  |  |
Change in fair value of warrant liabilities | $ 66,397,000 | $ (1,009,000) | $ 84,455,000 | $ (1,493,000) |
Star Peak Energy Transition Corp [Member] |  |  |  |  |
Liabilities: |  |  |  |  |
Fair value of warrants | 276,873,719 |  | 121,091,978 |  | $ 11,822,148
Transfer of assets from level 1 to level 2 | 0 |  | 0 |  |
Transfer of assets from level 2 to level 1 | 0 |  | 0 |  |
Transfers to / from Level 3 | 0 |  | 0 |  |
Change in fair value of warrant liabilities | 155,781,741 | $ 0 | (109,269,830) |  |
Star Peak Energy Transition Corp [Member] | Recurring |  |  |  |  |
Liabilities: |  |  |  |  |
Fair value of warrants |  |  | 121,091,978 |  |
Total fair value | 660,459,452 |  | 504,813,725 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Public warrants |  |  |  |  |
Liabilities: |  |  |  |  |
Fair value of warrants | 171,878,063 |  | 64,339,997 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Private warrants |  |  |  |  |
Liabilities: |  |  |  |  |
Fair value of warrants | 104,995,656 |  | 56,751,981 |  |
Star Peak Energy Transition Corp [Member] | Recurring | U.S. Treasury Securities |  |  |  |  |
Assets: |  |  |  |  |
Investments held in Trust Account | 383,585,733 |  | 383,721,747 |  |
Liabilities: |  |  |  |  |
Total fair value |  |  | 504,813,725 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Level 1 |  |  |  |  |
Liabilities: |  |  |  |  |
Total fair value | 555,463,796 |  | 448,061,744 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Level 1 | Public warrants |  |  |  |  |
Liabilities: |  |  |  |  |
Fair value of warrants | 171,878,063 |  | 64,339,997 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Level 1 | U.S. Treasury Securities |  |  |  |  |
Assets: |  |  |  |  |
Investments held in Trust Account | 383,585,733 |  | 383,721,747 |  |
Liabilities: |  |  |  |  |
Total fair value |  |  | 383,721,747 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Level 3 |  |  |  |  |
Liabilities: |  |  |  |  |
Fair value of warrants |  |  | 121,091,978 |  |
Total fair value | 104,995,656 |  | 56,751,981 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Level 3 | Private warrants |  |  |  |  |
Liabilities: |  |  |  |  |
Fair value of warrants | $ 104,995,656 |  | 56,751,981 |  |
Star Peak Energy Transition Corp [Member] | Recurring | Level 3 | U.S. Treasury Securities |  |  |  |  |
Liabilities: |  |  |  |  |
Total fair value |  |  | $ 121,091,978 |  |

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