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Commitments and Contingencies - Administrative Services Agreement and Underwriting Agreement (Details) - Star Peak Energy Transition Corp [Member] - USD ($) | Aug. 26, 2020 | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020
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Commitments And Contingencies [Line Items] |  |  |  |
Underwriting discount per unit | $ 0.20 |  |  |
Cash underwriting fees | $ 7,000,000.0 |  |  |
Deferred fee per unit | $ 0.35 |  |  |
Deferred underwriting commissions | $ 12,300,000 | $ 13,425,476 | $ 13,425,476 | $ 13,425,476
Over-allotment |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Cash underwriting fees | 700,000 |  |  |
Deferred underwriting commissions | $ 1,200,000 |  |  |

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- Details
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