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Commitments and Contingencies - Forward Purchase Agreement (Details) - Star Peak Energy Transition Corp [Member] - $ / shares |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Aug. 26, 2020 | Aug. 20, 2020 | Mar. 31, 2021 | Dec. 31, 2020
Commitments And Contingencies [Line Items] |  |  |  |
Share price per share |  |  |  | $ 10.00
Initial Public Offering |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Number of units issued | 3,358,504 | 35,000,000 |  |
Share price per share | $ 10.00 | $ 10.00 | $ 10.00 |
Over-allotment |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Number of units issued | 3,358,504 |  | 5,250,000 | 5,250,000
Share price per share | $ 10.00 |  | $ 10.00 | $ 10.00

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