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Financial risk management - Foreign currency risk (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Feb. 15, 2017
Foreign currency risk |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Appreciation of euro (Percentage) | 10.00% |  |
Depreciation of euro (percentage) | (10.00%) |  |
Loss on portion of cross currency swap accounted for at fair value through profit or loss on appreciation of the Euro by 10% over USD | $ 4,615 | $ 5,831 |
Gain on portion of cross currency swap accounted for at fair value through profit or loss on depreciation of the Euro by 10% against USD | (4,615) | $ (5,831) |
Senior Notes due 2022 issued by Ferroglobe PLC |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Principal amount |  |  | $ 150,000
Senior Notes due 2022 issued by Ferroglobe PLC | Foreign currency risk |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Principal amount | 150,000 |  |
Amount by which the cross currency swap exceeds debt instruments | $ 42,500 |  |

X
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- Definition The percentage of sensitivity of depreciation of euro currency. + References No definition available. + Details
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- Definition The amount by which the cross currency swap exceeds the principal amount of the entity's debt instruments. + References No definition available. + Details
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- Definition The amount of gain that would be recognized in respect of the portion of the cross currency swap accounted for at fair value through profit or loss if the Euro was to weaken against the US Dollar by 10%. + References No definition available. + Details
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- Definition The amount of loss that would be recognized in respect of the portion of the cross currency swap accounted for at fair value through profit or loss if the Euro was to strengthen against the US Dollar by 10%. + References No definition available. + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The nominal or face amount of a financial instrument, used to calculate payments made on that instrument. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
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- Details
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- Details
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