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Financial Instruments - Sensitivity Analysis of Interest Rate Risks (Detail) - Interest rate risk [member] - MXN ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Interest rate swaps [member] | FEMSA Entity Excluding Coca-Cola FEMSA [Member] |  |  |
Disclosure of Interest Rate Risk Exposure [line items] |  |  |
Effect on Equity | $ (354) | $ (432) | $ (359)
Change in interest rate | (1.00%) | (1.00%) | (1.00%)
Interest rate swaps [member] | Coca-Cola FEMSA [member] |  |  |
Disclosure of Interest Rate Risk Exposure [line items] |  |  |
Effect on Equity |  | $ (37) | $ (1,976)
Change in interest rate |  | (1.00%) | (1.00%)
Unhedged Portion Bank Loans [member] |  |  |
Disclosure of Interest Rate Risk Exposure [line items] |  |  |
Change in interest rate | 1.00% | 1.00% | 1.00%
Effect on profit loss | $ (110) | $ (50) | $ (145)

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- Definition Change in basis point effect on equity. + References No definition available. + Details
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- Definition Change in interest rate. + References No definition available. + Details
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- Definition Change in interest rate effect on profit loss. + References No definition available. + Details
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- Definition Disclosure of interest rate risk exposure line items. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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