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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
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 derivative warrant liabilities.

+ References

No definition available.

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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

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