Financial Instruments - Significant Unobservable Inputs (Details) - Internal Models with Significant Unobservable Inputs (Level 3) - MXN ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Reconciliation for all assets and liabilities measured at fair value
Balance at beginning of year	$ 38,298,606	$ 35,042,577
Included in other comprehensive income	(1,903,423)	3,256,029
Balance at the end of year	$ 36,395,183	$ 38,298,606

The gains (losses) recognised in other comprehensive income on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2017-01-01
-Paragraph 93
-Subparagraph e
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2017-03-01&anchor=para_93_e_ii&doctype=Standard
-URIDate 2017-03-09

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