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Fair Value Measurements - Change in the fair value of the derivative warrant liabilities (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Change in the fair value of the derivative warrant liabilities
Beginning balance at January 1	$ 95,342,000
Change in fair value	66,397,000
Ending balance at December 31	161,486,000	$ 95,342,000
Star Peak Energy Transition Corp [Member] | Level 3
Change in the fair value of the derivative warrant liabilities
Beginning balance at January 1	121,091,978	11,822,148
Change in fair value	155,781,741	109,269,830
Ending balance at December 31	$ 276,873,719	$ 121,091,978

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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