Right of use assets and lease debt - Schedule of maturity of lease liabilities (Detail) $ in Thousands, $ in Millions	Dec. 31, 2020 MXN ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 MXN ($)
Disclosure of maturity analysis of operating lease payments [line items]
Short term	$ 25,067,905	$ 1,257	$ 25,894,711
Long term	84,259,336	$ 4,224	$ 94,702,022
Total	$ 109,327,241

The amount of current lease liabilities. [Refer: Lease liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2020-01-01
-Paragraph 47
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2020-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2020-01-01

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration.

+ References

+ Details

Name:	ifrs-full_LeaseLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of non-current lease liabilities. [Refer: Lease liabilities]

+ References

+ Details

Name:	ifrs-full_NoncurrentLeaseLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant