XML 143 R127.htm IDEA: XBRL DOCUMENT v3.19.1

Employee Benefits - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018
Mexican subsidiaries [member]
Disclosure of defined benefit plans [line items]
Plan asset investment for related parties, percentage	10.00%
Discount rates [member]
Disclosure of defined benefit plans [line items]
Impact on absolute terms of variation in the assumptions on net defined benefit liability	1.00%
Bottom of range [member] | Mexican Federal Government instruments [member]
Disclosure of defined benefit plans [line items]
Fund assets, percentage	30.00%

X

- Definition

Percentage of fund assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	fmx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage of plan asset investment for related parties.

+ References

No definition available.

+ Details

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Namespace Prefix:	fmx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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

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

X

- Definition

The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 145
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_145_a&doctype=Standard
-URIDate 2018-03-16

+ Details

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X

- Details

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Namespace Prefix:
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X

- Details

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Namespace Prefix:
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Period Type:

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
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