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Stockholders' Equity - Common Stock Shares (Details)		3 Months Ended	12 Months Ended
	Jul. 13, 2020 shares	Mar. 31, 2021 Vote $ / shares shares	Dec. 31, 2020 Vote $ / shares shares	Aug. 26, 2020 shares	Dec. 31, 2019 $ / shares shares	Dec. 31, 2018 shares	Nov. 08, 2018 shares
Class of Stock [Line Items]
Common stock, shares authorized		474,728,323	474,728,323		386,728,323
Common stock, $0.000001 par value | $ / shares		$ 0.000001	$ 0.000001		$ 0.000001
Common stock, shares issued		17,694,228	11,228,371		9,392,682
Common shares, shares outstanding (in shares)		17,694,228	11,228,371
Outstanding shares		175,528,225	175,437,783		191,139,933	186,466,181
Star Peak Energy Transition Corp [Member]
Class of Stock [Line Items]
Outstanding shares			24,275,528
Star Peak Energy Transition Corp [Member] | Class A shares
Class of Stock [Line Items]
Common stock, shares authorized		400,000,000	400,000,000
Common stock, $0.000001 par value | $ / shares		$ 0.0001	$ 0.0001
Common stock, shares issued		29,717,672	14,082,976
Common shares, shares outstanding (in shares)		29,717,672	14,082,976
Common shares outstanding including possible redemption		38,358,504	38,358,504
Outstanding shares		8,640,832	24,275,528
Percentage of issued and outstanding shares after the Initial Public Offering collectively held by initial stockholders		20.00%	20.00%
Star Peak Energy Transition Corp [Member] | Common Class B
Class of Stock [Line Items]
Common stock, shares authorized		40,000,000	40,000,000		40,000,000
Common stock, $0.000001 par value | $ / shares		$ 0.0001	$ 0.0001		$ 0.0001
Common shares, votes per share | Vote		1	1
Common stock, shares issued		9,589,626	9,589,626		10,062,500		2,875,000
Common shares, shares outstanding (in shares)	10,062,500	9,589,626	9,589,626		10,062,500
Maximum shares subject to forfeiture	1,312,500
Percentage of issued and outstanding shares after the Initial Public Offering collectively held by initial stockholders	20.00%
Star Peak Energy Transition Corp [Member] | Over-allotment | Common Class B
Class of Stock [Line Items]
Maximum shares subject to forfeiture		1,312,500	1,312,500	472,874	1,312,500

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The number of votes that each common share is entitled.

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Represents the percentage of issued and outstanding shares after the Initial Public Offering collectively held by initial stockholders.

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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