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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- 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.

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Property, plant and equipment (Narrative) (Details) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019 MXN ($)	Dec. 31, 2018 MXN ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 MXN ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 MXN ($)	Dec. 31, 2017 MXN ($)
Disclosure of detailed information about property, plant and equipment [line items]
Depreciation expense	$ 1,098,749	$ 1,102,331
Net Book Value				$ 16,737,595		$ 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			$ 41,500		$ 32,700