XML 136 R119.htm IDEA: XBRL DOCUMENT v3.19.1

Other liabilities - Stock Options (Detail)	12 Months Ended
	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 Option USD ($)
Disclosure of terms and conditions of share-based payment arrangement [line items]
Exercised during the period | Option		30,000
Ferroglobe PLC Equity Incentive Plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Outstanding at beginning of the period	757,365	264,933
Granted during the period	485,860	492,432
Expired/forfeited during the period | shares	(218,183)
Outstanding at end of the period	1,025,042	757,365

X

- Definition

The number of share options expired or forfeited in a share-based payment arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	gsm_
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Balance Type:	na
Period Type:	duration

X

- 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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X

- Definition

The number of share options outstanding in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph d
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-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2018-01-01
-Paragraph 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-URIDate 2018-03-16

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Balance Type:	na
Period Type:	instant

X

- Definition

The number of share options exercised in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph b
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_b_iv&doctype=Standard
-URIDate 2018-03-16

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X

- Definition

The number of share options granted in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph b
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_b_ii&doctype=Standard
-URIDate 2018-03-16

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- Details

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