v3.26.1

REDEEMABLE PREFERRED STOCK (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Jul. 10, 2025	Jul. 09, 2025	Mar. 31, 2026	Dec. 31, 2025
Temporary Equity [Line Items]
Preferred Stock, Conversion Terms			At the election of the DoW, the Series A Preferred Stock is convertible at any time into 13,320,013 shares of the Company’s common stock at an initial conversion price of $30.03 per share, subject to customary anti-dilution adjustments.
Preferred Stock, Redemption Terms			The Company’s Series A Preferred Stock is classified as redeemable preferred stock (i.e., temporary equity) outside of stockholders’ equity within the Company’s unaudited Condensed Consolidated Balance Sheets due to redemption rights for a deemed liquidation event that, in certain circumstances, is not solely within the Company’s control. The purpose of this classification is to convey that such a security may not be permanently part of equity and could result in a demand for cash, securities or other assets of the entity in the future.
Redeemable preferred stock, liquidation preference			$ 420,725	$ 413,489
Series A Convertible Preferred Stock
Temporary Equity [Line Items]
Cash consideration received		$ 400,000
Series A Convertible Preferred Stock \| United States Department of War
Temporary Equity [Line Items]
Issuance of Series A preferred stock (in shares)	400,000
Stated value of Series A Preferred Stock (per share)	$ 1,000
Series A Preferred Stock, Convertible, Shares Issuable	13,320,013
Conversion price of convertible preferred stock (usd per share)	$ 30.03
Redeemable preferred stock, liquidation preference			$ 420,700	$ 413,500

DoW Transactions, Cash Consideration Received

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The aggregate liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. 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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MP Materials Corp. / DE 10-Q