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Employee Benefits - Additional Information (Detail) - MXN ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Disclosure of defined benefit plans [line items] |  |  |
Plan assets including securities |  | $ 114 |
Current service costs included in cost of goods sold, administration and selling expenses | $ 408 | $ 359 | $ 343
Mexican subsidiaries [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Plan asset investment for related parties, percentage | 10.00% |  |
Bottom of range [member] | Mexican Federal Government instruments [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Fund assets, percentage | 30.00% |  |
Discount rates [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Impact on absolute terms of variation in the assumptions on net defined benefit liability | 0.50% |  |

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- Definition Percentage of fund assets. + References No definition available. + Details
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- Definition Percentage of plan asset investment for related parties. + References No definition available. + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_a&doctype=Standard -URIDate 2017-03-09 + Details
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- 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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- 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 2017-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_145_a&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_57_a&doctype=Standard -URIDate 2017-03-09 + 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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