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Business Combinations - Kintuk (Details) - USD ($) $ in Thousands |  | 11 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 01, 2018 | Dec. 31, 2018 | Dec. 31, 2018
Satisfied by: |  |  |
Gain on bargain purchase |  |  | $ 40,142
Kintuk |  |  |
Disclosure of detailed information about business combination [line items] |  |  |
Percentage of equity interests acquired | 100.00% |  |
IFRS Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets [Abstract] |  |  |
Other intangible assets | $ 45 |  |
Property, plant and equipment | 62,487 |  |
Non-current financial assets | 50 |  |
Total non-current assets acquired | 62,582 |  |
IFRS Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract] |  |  |
Inventories | 21,314 |  |
Trade and other receivables | 24,785 |  |
Other current assets | 1,397 |  |
Cash and cash equivalents | 29,530 |  |
Total current liabilities assumed | 77,026 |  |
Total assets acquired | 139,608 |  |
IFRS Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities [Abstract] |  |  |
Deferred tax liabilities | 90 |  |
Total non-current liabilities acquired | 90 |  |
IFRS Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities [Abstract] |  |  |
Trade and other payables | 18,048 |  |
Provisions | 735 |  |
Current income tax liabilities | 396 |  |
Other current liabilities | 4,066 |  |
Total current liabilities assumed | 23,245 |  |
Total liabilities assumed | 23,335 |  |
Net assets acquired | 116,273 |  |
Satisfied by: |  |  |
Cash | 49,909 |  |
Contingent consideration | 26,222 |  |
Acquisition Consideration | 76,131 |  |
Gain on bargain purchase | 40,142 |  |
Less: cash and cash equivalent balances acquired | (29,530) |  |
Net cash outflow arising on acquisition | $ 20,379 |  |
Fair value of trade receivables |  | $ 11,900 | 11,900
Gain loss relating to acquired receivables |  |  | 0
Kintuk | Minimum |  |  |
Satisfied by: |  |  |
Contingent consideration arrangements |  | 0 | 0
Kintuk | Maximum |  |  |
Satisfied by: |  |  |
Contingent consideration arrangements |  | 60,000 | 60,000
Ferroglobe Mangan Norge And Ferroglobe Manganese France Member |  |  |
Satisfied by: |  |  |
Revenue of combined entity |  |  | 2,289,931
profit of combined entity |  |  | $ 45,007
Ferroglobe Mangan Norge And Ferroglobe Manganese France Member | Minimum |  |  |
Satisfied by: |  |  |
Discount rates |  |  | 11.00%
Average simulated revenues |  |  | $ 269,256
Revenue of acquiree |  | 112,445 |
Loss of acquiree |  | 10,148 |
Ferroglobe Mangan Norge And Ferroglobe Manganese France Member | Maximum |  |  |
Satisfied by: |  |  |
Contingent consideration arrangements |  | 60,000 | $ 60,000
Period of contingent consideration applied to sales |  |  | 8 years 6 months
Discount rates |  |  | 11.50%
Average simulated revenues |  |  | $ 312,526
Revenue of acquiree |  | 117,852 |
Loss of acquiree |  | $ 10,436 |

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