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Provisions - Employee obligations - France - (Details) - France $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Changes in net defined benefit liability (asset) [abstract] |  |
Percentage change in cost of provision | 1 | 1
Change in obligation | $ 3,664 | $ 3,970
Not later than one year |  |
Estimated Future Benefit Payments [Abstract] |  |
Estimated future benefit payments | 1,597 |
Later than one year and not later than two years |  |
Estimated Future Benefit Payments [Abstract] |  |
Estimated future benefit payments | 977 |
Later than two years and not later than three years |  |
Estimated Future Benefit Payments [Abstract] |  |
Estimated future benefit payments | 1,179 |
Later than three years and not later than four years |  |
Estimated Future Benefit Payments [Abstract] |  |
Estimated future benefit payments | 1,329 |
Later than four years and not later than five years |  |
Estimated Future Benefit Payments [Abstract] |  |
Estimated future benefit payments | 2,007 |
Later than five years and not later than ten years [member] |  |
Estimated Future Benefit Payments [Abstract] |  |
Estimated future benefit payments | 8,628 |
Ferro Pem S A S [Member] | Present value of defined benefit obligation [member] |  |
Changes in net defined benefit liability (asset) [abstract] |  |
Obligations at beginning of year | 29,768 | 29,733
Current service cost | 1,678 | 1,834
Borrowing costs | 470 | 383
Actuarial differences | (700) | (4,570)
Benefits paid | (1,818) | (1,471)
Exchange differences | (1,349) | 3,859
Obligations at end of year | $ 28,049 | $ 29,768

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- Definition The increase (decrease) in a defined benefit obligation that would have been caused by an change in a cost of provision that was reasonably possible at the end of the reporting period. + References No definition available. + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_c&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from changes in foreign exchange rates. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_e&doctype=Standard -URIDate 2018-03-16 + Details
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