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Financial Instruments - Disclosure of Net Effect of Expired Contracts Did Not Meet Hedging Criteria for Accounting Purposes (Detail) - MXN ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2015
Derivative financial instruments did not meet hedging criteria [member] | Cross-currency swaps [member] | Market value gain on financial instruments [member]
Disclosure of detailed information about hedges [line items]
Net effects derivative contracts hedging criteria	$ (438)	$ 204

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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 gains resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 85
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_85&doctype=Standard
-URIDate 2017-03-09

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