XML 155 R135.htm IDEA: XBRL DOCUMENT
v3.21.1

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

X
- 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
Name: | ifrs-full_DisclosureOfHedgeAccountingLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24A_a&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_HedgingInstrumentAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 -Number 1 -IssueDate 2020-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_NotionalAmount
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | ifrs-full_HedgingInstrumentsAxis=fmx_TreasuryLockContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_NotLaterThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |