Annual production capacity.

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Cumulative consumer price inflation rate.

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Disclosure of significant accounting policies [line items]

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Increase decrease in debt and other current accounts receivable.

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Increase decrease in debt due to conversion of convertible instruments.

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Minimum requirement of percentage of equity interest.

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Number Of Cement Plants Sold

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Number Of Quarries Sold

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Number Of Ready Mix Plants Sold

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Number of shares issued on conversion of foreign currency convertible notes.

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Property plant and equipment acquired through capital leases.

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Threshold to declare and maintain a hedge.

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- Definition

The applicable income tax rate.

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The average exchange rate used by the entity. Exchange rate is the ratio of exchange for two currencies.

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The spot exchange rate at the end of the reporting period. Exchange rate is the ratio of exchange for two currencies. Spot exchange rate is the exchange rate for immediate delivery.

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The increase (decrease) in equity resulting from the appropriation of retained earnings. [Refer: Retained earnings]

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The increase (decrease) in equity resulting from the conversion of convertible instruments.

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The increase (decrease) in equity resulting from share-based payment transactions. [Refer: Equity]

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The useful lives or amortisation rates used for intangible assets other than goodwill. [Refer: Intangible assets other than goodwill]

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Significant Accounting Policies - Additional Information (Detail) shares in Millions, $ in Millions		12 Months Ended
	Apr. 05, 2017 Quarry Plant MT	Dec. 31, 2017 MXN ($) shares	Dec. 31, 2016 MXN ($)	Dec. 31, 2015 MXN ($) shares
Disclosure of significant accounting policies [line items]
Capitalization of retained earnings		$ 0	$ 0	$ 0
Share-based compensation		817	742	655
Decrease in debt		5,468		4,517
Increase (decrease) through conversion of convertible instruments		$ 5,729		$ 5,051
Issuance of convertible subordinated notes \| shares		43		42
Increase in debt and in other current accounts receivable			$ 148
Minimum equity interest for significant influence		20.00%
Useful life of intangible asset		3 to 20 years
Statutory income tax rate		30.00%	30.00%	30.00%
Mexico [member]
Disclosure of significant accounting policies [line items]
Statutory income tax rate		30.00%	30.00%	30.00%
Computer software [member]
Disclosure of significant accounting policies [line items]
Useful life of intangible asset		5 years
Extraction rights [member]
Disclosure of significant accounting policies [line items]
Useful life of intangible asset		30 to 100 years
Bottom of range [member]
Disclosure of significant accounting policies [line items]
Cumulative inflation rate over the last three years		100.00%
Threshold to declare and maintain a hedge		0.80
Top of range [member]
Disclosure of significant accounting policies [line items]
Threshold to declare and maintain a hedge		1.25
Announcement of Plan to Discontinue Operation [Member] \| Duna-Drava Cement Kft [Member]
Disclosure of significant accounting policies [line items]
Number of cement plats sold \| Plant	3
Number of quarries sold \| Quarry	2
Number of ready mix plants sold \| Plant	7
Annual production capacity of cement plant sold \| MT	2.4
Mobile equipment [member]
Disclosure of significant accounting policies [line items]
Carrying amount of assets acquired through capital lease		$ 2,096	$ 7	$ 63
Issued capital and additional paid-in capital [member]
Disclosure of significant accounting policies [line items]
Capitalization of retained earnings		9,464	6,970	7,617
Additional paid-in capital [member]
Disclosure of significant accounting policies [line items]
Capitalization of retained earnings		9,459	6,966	7,613
Share-based compensation		791	$ 742	655
Increase (decrease) through conversion of convertible instruments		7,059		5,982
Equity Reserve [member]
Disclosure of significant accounting policies [line items]
Increase (decrease) through conversion of convertible instruments		(1,334)		(934)
Common Stock [member]
Disclosure of significant accounting policies [line items]
Increase (decrease) through conversion of convertible instruments		$ 4		$ 3
US Dollar [member]
Disclosure of significant accounting policies [line items]
Closing exchange rate		19.6500	20.7200	17.2300
Average exchange rate		18.8800	18.7200	15.9800