Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Summary of Significant Accounting Policies (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Mar. 31, 2021	Nov. 27, 2020	Sep. 30, 2020	Aug. 31, 2020	Dec. 31, 2019
Temporary equity, shares outstanding	6,000,000	6,000,000	6,000,000	6,000,000				6,000,000
Unrecognized tax benefits		$ 0
Purchase of aggregate shares		15,000	55,000
SPRING VALLEY ACQUISITION CORP
Unrecognized tax benefits	$ 0	$ 0
Unrecognized tax benefits accrued for interest and penalties	0	$ 0
Accrued Income Taxes, Current	$ 0
Class A Common Stock \| SPRING VALLEY ACQUISITION CORP
Temporary equity, shares outstanding	23,000,000	23,000,000
Class A Common Stock \| SPRING VALLEY ACQUISITION CORP \| Private Placement Warrants
Purchase of aggregate shares	22,529,000	22,529,000
Class A Ordinary Shares Subject to Possible Redemption. \| SPRING VALLEY ACQUISITION CORP
Temporary equity, shares outstanding		23,000,000	23,000,000			23,000,000	23,000,000
Class A Ordinary Shares Subject to Possible Redemption. \| SPRING VALLEY ACQUISITION CORP \| Initial Public Offering
Temporary equity, shares outstanding		23,000,000			23,000,000