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Class A Ordinary Shares Subject to Possible Redemption (Details) - USD ($) | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2021 | Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Temporary Equity [Line Items] |  |  |  |  |
Temporary equity, shares outstanding | 6,000,000 | 6,000,000 | 6,000,000 | 6,000,000 | 6,000,000
Class A ordinary shares subject to possible redemption | $ 2,140,000 | $ 2,140,000 |  | $ 2,140,000 |
SPRING VALLEY ACQUISITION CORP |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |
Class A ordinary shares subject to possible redemption | $ 232,300,000 | $ 232,300,000 |  | $ 232,300,000 |
SPRING VALLEY ACQUISITION CORP | Class A Common Stock |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |
Temporary equity, par value | $ 0.0001 | $ 0.0001 |  |  |
Temporary equity, shares outstanding | 23,000,000 | 23,000,000 |  |  |
SPRING VALLEY ACQUISITION CORP | Class A Ordinary Shares Subject to Redemption |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |
Temporary equity, shares authorized | 300,000,000 |  |  | 300,000,000 |
Temporary equity, par value | $ 0.0001 |  |  | $ 0.0001 |
Temporary equity, shares outstanding | 23,000,000 |  |  | 23,000,000 |
Gross proceeds from Initial Public Offering | $ 230,000,000 |  |  |  |
Fair value of Public Warrants at issuance | (12,650,000) |  |  |  |
Offering costs allocated to Class A ordinary shares subject to possible redemption | (11,743,101) |  |  |  |
Accretion on Class A ordinary shares subject to possible redemption amount | 26,693,101 |  |  |  |
Class A ordinary shares subject to possible redemption | $ 232,300,000 |  |  |  |

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