The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]]

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The fair value, at the acquisition date, of equity interests of the acquirer transferred as consideration in a business combination. [Refer: Business combinations [member]]

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The number of instruments or interests issued or issuable at acquisition date for equity interests of the acquirer transferred as consideration in a business combination.

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The percentage of voting equity interests acquired in a business combination. [Refer: Business combinations [member]]

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Number of common shares acquired per share price.

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Production capacity.

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Significant events (Details) $ / shares in Units, $ in Thousands, $ in Thousands	Dec. 31, 2018 USD ($) shares $ / shares	May 01, 2018 T	Dec. 05, 2017 MXN ($) shares
Senales del Norte S.A. de C.V. [Member]
Disclosure of detailed information about business combination [line items]
Shares acquired by subsidiary, value \| $			$ 122,660
Senales del Norte S.A. de C.V. [Member] \| Class I Shares [Member]
Disclosure of detailed information about business combination [line items]
Shares acquired by subsidiary			2,000
Percentage of capital stock acquired by subsidiary			100.00%
Senales del Norte S.A. de C.V. [Member] \| Class II Shares [Member]
Disclosure of detailed information about business combination [line items]
Shares acquired by subsidiary			3,908,782
Percentage of capital stock acquired by subsidiary			100.00%
First Steel Mill of ArcelorMittal in Brazil [Member]
Disclosure of detailed information about business combination [line items]
Production capacity \| T		600,000
Second Steel Mill of ArcelorMittal in Brazil [Member]
Disclosure of detailed information about business combination [line items]
Production capacity \| T		120,000
SimRep Corporation [Member]
Disclosure of detailed information about business combination [line items]
Shares acquired by subsidiary	83,862
Percentage of capital stock acquired by subsidiary	99.41%
Number of common shares acquired per share price \| $ / shares	$ 3,454
Amount of Consideration \| $	$ 289,660