Schedule I - Notes to Appendix (Details) - Separate € in Millions |
12 Months Ended | |||
|---|---|---|---|---|
|
Dec. 31, 2025
USD ($)
|
Dec. 31, 2024
USD ($)
|
Dec. 31, 2024
EUR (€)
|
Dec. 31, 2024
USD ($)
|
|
| Debt Instruments | ||||
| Cash fee | $ 35,760,000 | $ 6,000 | ||
| Ferroglobe Holding Company, LTD [Member] | ||||
| Debt Instruments | ||||
| Amounts payable, related party transactions | 10,300,000 | $ 57,900,000 | ||
| Sociedad Estatal de Participaciones Industriales loan | Contingent liability for guarantees [member] | ||||
| Debt Instruments | ||||
| Estimated financial effect of contingent liabilities | € 34.5 | 38,300,000 | ||
| NMTC Program | Contingent liability for guarantees [member] | ||||
| Debt Instruments | ||||
| Estimated financial effect of contingent liabilities | 7,000,000 | |||
| Promissory note | Ferroglobe USA Metallurgical, Inc. | ||||
| Debt Instruments | ||||
| Amounts payable, related party transactions | $ 3,500,000 | $ 3,500,000 | ||