Financial Instruments - Treasury Lock contracts (Detail) - Treasury Lock contracts [Member] - 0-1 year [member] $ in Millions	Dec. 31, 2019 MXN ($)
Disclosure of detailed information about hedges [line items]
Notional	$ 10,365
Fair Value Asset	$ 102

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.

No definition available.

+ Details

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- Definition

The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 24A
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-URIDate 2020-01-01

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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2020-01-01
-Paragraph 112
-Subparagraph c
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- Details

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- Details

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