Investments in Associates and Joint Ventures - Summary of Associates and Joint Ventures (Detail) - MXN ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Carrying Amount	$ 96,097	$ 128,601
Promotora Industrial Azucarera, S.A. de C.V. ("PIASA") [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Promotora Industrial Azucarera, S.A. de C.V. (“PIASA”)
Principal Activity	Sugar production
Place of Incorporation	Mexico
Ownership Percentage	36.40%	36.40%
Carrying Amount	$ 2,933	$ 2,657
Industria Envasadora De Queretaro SA De CVIEQSA [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Industria Envasadora de Queretaro, S.A. de C.V. (“IEQSA”)
Principal Activity	Canned bottling
Place of Incorporation	Mexico
Ownership Percentage	26.50%	26.50%
Carrying Amount	$ 177	$ 177
Industria Mexicana de Reciclaje, S.A. de C.V. ("IMER") [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Industria Mexicana de Reciclaje, S.A. de C.V. ("IMER")
Principal Activity	Recycling
Place of Incorporation	Mexico
Ownership Percentage	35.00%	35.00%
Carrying Amount	$ 121	$ 100
Jugos del Valle, S.A.P.I. de C.V. [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Jugos del Valle, S.A.P.I. de C.V.
Principal Activity	Beverages
Place of Incorporation	Mexico
Ownership Percentage	26.30%	26.30%
Carrying Amount	$ 1,560	$ 1,574
KSP Participacoes LTDA [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	KSP Partiçipações, L.T.D.A.
Principal Activity	Beverages
Place of Incorporation	Brazil
Ownership Percentage	38.70%	38.70%
Carrying Amount	$ 117	$ 126
Leao Alimentos e Bebidas, LTDA [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Leao Alimentos e Bebidas, L.T.D.A.
Principal Activity	Beverages
Place of Incorporation	Brazil
Ownership Percentage	24.70%	27.70%
Carrying Amount	$ 3,001	$ 3,282
UBI 3 Participacoes, LTDA [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	UBI 3 Participações Ltda (Ades)
Principal Activity	Beverages
Place of Incorporation	Brazil
Ownership Percentage	26.00%
Carrying Amount	$ 391
Other Investments In Coca Cola FEMSAs Companies [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Other investments in Coca-Cola FEMSA's companies
Principal Activity	Various
Place of Incorporation	Various
Carrying Amount	$ 228	64
Compania Panamena de Bebidas, S.A.P.I. de C.V. [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Carrying Amount	$ 2,036	$ 1,911
Joint ventures	Compañía Panameña de Bebidas, S.A.P.I. de C.V.
Principal Activity	Beverages
Place of Incorporation	Mexico
Ownership Percentage	50.00%	50.00%
Dispensadoras de Cafe, S.A.P.I. de C.V. [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Carrying Amount	$ 153	$ 145
Joint ventures	Dispensadoras de Café, S.A.P.I. de C.V.
Principal Activity	Services
Place of Incorporation	Mexico
Ownership Percentage	50.00%	50.00%
Estancia Hidromineral Itabirito, LTDA [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Carrying Amount		$ 96
Joint ventures	Estancia Hidromineral Itabirito, L.T.D.A
Principal Activity	Bottling and distribution
Place of Incorporation	Brazil
Ownership Percentage		50.00%
Coca Cola FEMSA Philippines Inc CCFPI [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Carrying Amount		$ 11,460
Joint ventures	Coca-Cola FEMSA Philippines, Inc. ("CCFPI")
Principal Activity	Bottling
Place of Incorporation	Philippines
Ownership Percentage		51.00%
Fountain Agua Mineral, LTDA [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Carrying Amount	$ 784	$ 765
Joint ventures	Fountain Agua Mineral, L.T.D.A
Principal Activity	Beverages
Place of Incorporation	Brazil
Ownership Percentage	50.00%	50.00%
FEMSA Comercio [member] \| Cafe Del Pacifico SAPI De CV Caffenio [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Café del Pacifico, S.A.P.I. de C.V. (Caffenio)
Principal Activity	Coffee
Place of Incorporation	Mexico
Ownership Percentage	40.00%	40.00%
Carrying Amount	$ 539	$ 493
Other Investments [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Other investments
Principal Activity	Various
Place of Incorporation	Various
Carrying Amount	$ 337	$ 482
Heineken [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Joint ventures	Heineken
Principal Activity	Beverages
Place of Incorporation	The Netherlands
Ownership Percentage	14.80%	20.00%
Carrying Amount	$ 83,720	$ 105,268

Disclosure of Investments in Associates and Joint Ventures [Line Items]

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The country in which a joint venture of the entity is incorporated. [Refer: Joint ventures [member]]

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The country in which an associate of the entity is incorporated. [Refer: Associates [member]]

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The description of the nature of the entity's relationship with an associate (for example, describing the nature of the activities of the associate and whether they are strategic to the entity's activities). [Refer: Associates [member]]

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The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

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The name of an associate. [Refer: Associates [member]]

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The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]]

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