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Summary of Significant Accounting Policies - Derivative warrant liabilities (Details) - Star Peak Energy Transition Corp [Member] - shares | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Class of Stock [Line Items] |  |
Common stock warrants issued | 19,967,302 | 19,967,302
Initial Public Offering |  |
Class of Stock [Line Items] |  |
Common stock warrants issued | (12,786,168) | (12,786,168)
Private Placement |  |
Class of Stock [Line Items] |  |
Common stock warrants issued | (7,181,134) | (7,181,134)

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- Definition Number of common stock warrants issued classified as derivative warrant liabilities. + References No definition available. + Details
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- Details
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- Details
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- Details
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