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v3.21.1

Initial Public Offering (Details) - Star Peak Energy Transition Corp [Member] - USD ($) |  |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Aug. 26, 2020 | Aug. 20, 2020 | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Price per share |  |  |  | $ 10.00 |
Deferred underwriting commissions in connection with the initial public offering | $ 12,300,000 |  | $ 13,425,476 | $ 13,425,476 | $ 13,425,476
Initial Public Offering |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Number of units issued | 3,358,504 | 35,000,000 |  |  |
Price per share | $ 10.00 | $ 10.00 | $ 10.00 |  |
Gross proceeds from sale of units |  | $ 350,000,000.0 |  |  |
Offering costs |  | 20,000,000.0 |  |  |
Deferred underwriting commissions in connection with the initial public offering |  | $ 12,300,000 |  |  |
Number of shares in a unit |  |  | 1 | 1 |
Number of warrants in a unit |  |  | 0.33 | 0.33 |
Number of shares issuable per warrant |  |  | 1 | 1 |
Exercise price of warrants |  |  | $ 11.50 | $ 11.50 |
Over-allotment |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Number of units issued | 3,358,504 |  | 5,250,000 | 5,250,000 |
Price per share | $ 10.00 |  | $ 10.00 | $ 10.00 |
Gross proceeds from sale of units | $ 33,600,000 |  |  |  |
Offering costs | 1,900,000 |  |  |  |
Deferred underwriting commissions in connection with the initial public offering | $ 1,200,000 |  |  |  |

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