The amount of depreciation expense. Depreciation is the systematic allocation of depreciable amounts of tangible assets over their useful lives.

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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.

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The amount of impairment loss recognised in profit or loss for property, plant and equipment. [Refer: Impairment loss recognised in profit or loss; Property, plant and equipment]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period.

+ References

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The cash outflow for the purchases of property, plant and equipment, classified as investing activities. [Refer: Property, plant and equipment]

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- Definition

Capitalized amount from labor and manufacturing overhead related to construction.

+ References

No definition available.

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Property, plant and equipment (Narrative) (Details) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2018 MXN ($)	Dec. 31, 2017 MXN ($)	Dec. 31, 2016 MXN ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2018 MXN ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 MXN ($)	Dec. 31, 2015 USD ($)
Disclosure of detailed information about property, plant and equipment [line items]
Depreciation expense		$ 1,102,331	$ 1,340,375
Invested amount in equipment		$ 1,994,465	$ 3,039,501	$ 3,100,259
Net Book Value				$ 14,491,000		$ 16,970,832		$ 15,737,081
Lorain Ohio facility [Member] \| USD [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Net Book Value	$ 32,700						$ 32,200
Impairment charge	$ 130,700
Republic Steel [Member] \| USD [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Net Book Value									$ 130,700
Republic Steel [Member] \| Electric arc furnace and associated equipment [Member] \| USD [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Invested amount in equipment					$ 158,800
Capitalized amount from labor and manufacturing overhead related to construction					$ 45,400