Commitments payments in cash.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of ordinary shares repurchased.

+ References

No definition available.

+ Details

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- Definition

Share-based compensation annual grant percentage.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Share-based compensation program service period.

+ References

No definition available.

+ Details

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- Definition

Share-based compensation shares expected to be issued.

+ References

No definition available.

+ Details

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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 amount of expense from share-based payment transactions with employees.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2018-03-16

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of share options granted in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph b
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_b_ii&doctype=Standard
-URIDate 2018-03-16

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average share price. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_c&doctype=Standard
-URIDate 2018-03-16

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Executive Share-based Compensation - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018 MXN ($) shares	Dec. 31, 2018 COP ($) shares	Dec. 31, 2017 MXN ($)	Dec. 31, 2017 COP ($)	Dec. 31, 2016 MXN ($)	Dec. 31, 2016 COP ($)
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation expense	$ 706,000,000		$ 817,000,000		$ 742,000,000
Commitment payments in cash	$ 0		$ 0
CEMEX Latam Holdings, S.A [member]
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation program service period	4 years	4 years
Share-based compensation shares issued	258,511	258,511	172,981	172,981	271,461	271,461
Share-based compensation shares expected to be issued \| shares	1,162,186
Weighted average price per granted shares		$ 12,347		$ 13,077		$ 13,423
CEMEX Holdings Philippines, Inc. [member]
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation shares issued	0	0
Own shares repurchased \| shares	871,189	871,189
CPO [Member]
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation program service period	4 years	4 years	4 years	4 years	3 years	3 years
Share-based compensation annual grant percentage	25.00%	25.00%
Share-based compensation shares issued	49,300,000	49,300,000	53,200,000	53,200,000	53,900,000	53,900,000
Share-based compensation shares expected to be issued \| shares	69,500,000
Weighted average price per granted shares	$ 13.61		$ 14.28		$ 13.79
CPO [Member] \| Bottom of range [member]
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation annual grant percentage			0.00%	0.00%
CPO [Member] \| Top of range [member]
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation annual grant percentage			200.00%	200.00%