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v3.20.1

Employee Benefits - Additional Information (Detail) - MXN ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of defined benefit plans [line items] |  |  |
Percentage of reasonably possible decrease in actuarial assumption | 1.00% |  |
Cost of sales [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Labor expense | $ 433 |  |
Administrative expenses [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Labor expense |  | $ 468 |
Selling expenses [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Labor expense |  |  | $ 374
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% |  |

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- Definition The reasonably possible percentage of the decrease 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 2019-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_145_a&doctype=Standard -URIDate 2019-03-27 + Details
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- 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 2019-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_145_a&doctype=Standard -URIDate 2019-03-27 + Details
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