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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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Number of common stock warrants issued classified as derivative warrant liabilities.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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