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Fair Value Measurements - company's financial assets and liabilities that are measured at fair value on a recurring basis (Details) - SPRING VALLEY ACQUISITION CORP - Recurring - USD ($) | Mar. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
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Level 1 |  |  |
Assets, Fair Value Disclosure [Abstract] |  |  |
Investments held in Trust Account - Mutual funds | $ 232,344,333 | $ 232,320,939 | $ 232,301,973
Private Placement Warrant | Level 1 |  |  |
Liabilities: |  |  |
Derivative Warrant Liabilities, Fair Value Disclosure |  | 14,375,000 | 18,975,000
Private Placement Warrant | Level 3 |  |  |
Liabilities: |  |  |
Derivative Warrant Liabilities, Fair Value Disclosure |  | $ 14,774,000 | $ 14,685,000

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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + 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 (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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