Accounts Payable, Accrued Liabilities and Asset Retirement Obligations - Summary of Balance of Accrued Liabilities (Detail) $ in Thousands, $ in Millions	Dec. 31, 2017 MXN ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 MXN ($)
Current liabilities
Direct employee benefits payable	$ 16,673,627		$ 19,713,160
Contingencies	51,079,131		50,766,070
Total	$ 67,752,758	$ 3,425	$ 70,479,230

The amount of accruals for employee benefits (other than termination benefits) that are expected to be settled wholly within twelve months after the end of the annual reporting period in which the employees render the related services. [Refer: Accruals classified as current]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 78
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_78&doctype=Standard
-URIDate 2017-03-09

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