The amount of liabilities of uncertain timing or the amount recognised when: (a) the entity has a present obligation (legal or constructive) as a result of a past event; (b) it is probable (ie more likely than not) that an outflow of resources embodying economic benefits will be required to settle the obligation; and (c) a reliable estimate can be made of the amount of the obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 54
-Subparagraph l
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_l&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_Provisions
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Other Liabilities, Provisions, Contingencies and Commitments - Nature and Amount of Loss Contingencies (Detail) - MXN ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jan. 01, 2015
Disclosure of financial liabilities [line items]
Provisions	$ 12,855	$ 16,428
Indirect taxes [Member]
Disclosure of financial liabilities [line items]
Provisions	6,836	11,065	$ 1,725	$ 2,271
Labor [Member]
Disclosure of financial liabilities [line items]
Provisions	2,723	2,578	1,372	1,587
Legal [Member]
Disclosure of financial liabilities [line items]
Provisions	$ 3,296	$ 2,785	$ 318	$ 427