Commitments payments in cash.

No definition available.

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- Definition

Number of ordinary shares repurchased.

+ References

No definition available.

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- Definition

Share-based compensation annual grant percentage.

+ References

No definition available.

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- Definition

Share-based compensation program service period.

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No definition available.

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- Definition

Share-based compensation shares expected to be issued.

+ References

No definition available.

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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.

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- Definition

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

+ References

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- Definition

The number of instruments granted in share-based payment arrangement.

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- Definition

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

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- Definition

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

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Executive Share-based Compensation - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020 USD ($) shares $ / shares	Dec. 31, 2019 USD ($) shares $ / shares	Dec. 31, 2018 USD ($) shares $ / shares	Dec. 31, 2017	Dec. 31, 2016
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation expense \| $	$ 29,000,000	$ 32,000,000	$ 34,000,000
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
Share-based compensation shares issued	1,383,518	393,855	258,511
Share-based compensation shares expected to be issued	2,895,944
Weighted average price per granted shares \| $ / shares	$ 0.72	$ 1.31	$ 2.14
CEMEX Holdings Philippines, Inc. [member]
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Own shares repurchased	11,546,350	4,961,130
CPO [Member]
Disclosure of Terms and Conditions of Share-based Payment Arrangement [Line Items]
Share-based compensation program service period	4 years			4 years	3 years
Share-based compensation annual grant percentage	(25.00%)	(25.00%)
Share-based compensation shares issued	83,800,000	27,400,000	49,300,000
Share-based compensation shares issued		21,200,000
Share-based compensation shares expected to be issued	248,400,000
Weighted average price per granted shares \| $ / shares	$ 0.3379	$ 0.6263	$ 0.7067
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%
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%