Equity forward contract settled by shares.

No definition available.

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- Definition

Equity forward contracts early settled by shares.

+ References

No definition available.

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- Definition

Financial assets at fair values through profit or loss.

+ References

No definition available.

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- Definition

Net foreign exchange gain (loss).

+ References

No definition available.

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- Definition

payments on contract.

+ References

No definition available.

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- Definition

The interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
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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 fair value of financial assets. [Refer: At fair value [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2020-01-01
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- Definition

The fair value of financial liabilities. [Refer: At fair value [member]; Financial liabilities]

+ References

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- Definition

The gain (loss) recognised on designation of a financial instrument, or a proportion of it, as measured at fair value through profit or loss, because a credit derivative is used to manage the credit risk of that financial instrument. [Refer: Credit risk [member]; Derivatives [member]; Financial instruments, class [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The gain (loss) recognised on derecognition of financial instruments whose fair value previously could not be reliably measured. [Refer: Financial instruments, class [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
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- Definition

The net loss arising from foreign exchange differences. [Refer: Foreign exchange gain (loss)]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-IssueDate 2020-01-01
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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Financial Instruments - Additional Information - Derivative Financial Instruments (Detail) - USD ($) shares in Millions, $ in Millions		12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items]
Gains and (losses) related to recognition of changes in fair values of the derivative instruments		$ 39	$ 1	$ (17)
Financial Income And Other Items [Member] \| CEMEX SAB De CV April 2024 Notes [Member]
Disclosure of detailed information about financial instruments [line items]
Gain (loss) due to changes in estimated fair value		3
Fuel Price Forward Contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial instrument, Notional amount		128	96
Financial liabilities at estimated fair value		5	1
Gain (loss) due to changes in estimated fair value		7	(15)	35
Net Investment Hedges [member] \| Forward Contract [Member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial instrument, Notional amount		741
Net foreign exchange gain (loss)			126	59
Net Investment Hedges [member] \| Top of range [member] \| Forward Contract [Member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial instrument, Notional amount		1,250
Equity Investments [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at fair value through profit or loss		$ 1	$ 2	26
Forward contract to be settled in shares		4.7	13.9
Forward contract settled in cash		9.2	6.9
Equity Investments [Member] \| Forward Contract [Member]
Disclosure of detailed information about financial instruments [line items]
Net foreign exchange gain (loss)		$ 53
Interest Rate Swap Contract [Member] \| Cemex [Member] \| Financial Income And Other Items [Member]
Disclosure of detailed information about financial instruments [line items]
Payments on Contract	$ 14
Interest Rate Swap Contract [Member] \| Top of range [member] \| Cemex [Member]
Disclosure of detailed information about financial instruments [line items]
Borrowings, interest rate	3.05%
Interest Rate Swap Contract [Member] \| Bottom of range [member] \| Cemex [Member]
Disclosure of detailed information about financial instruments [line items]
Borrowings, interest rate	2.56%
Interest Rate Swap Contract [Member] \| Electric Energy [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at estimated fair value				$ 11
Borrowings, interest rate				5.40%
Interest Rate Swap Contract [Member] \| Loans from banks at floating interest rate [member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial instrument, Notional amount		1,000
Financial liabilities at estimated fair value		44	$ 35
Gain (loss) due to changes in estimated fair value		9	$ 26
Interest Rate Swap Contract [Member] \| Loans from banks at floating interest rate [member] \| Cemex [Member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial instrument, Notional amount		334
Financial liabilities at estimated fair value		3
Gain (loss) due to changes in estimated fair value		3
Foreign exchange forwards related to forecasted transactions [member] \| 2017 Credit Agreement [member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial instrument, Notional amount		397
Foreign exchange forwards related to forecasted transactions [member] \| Financial Income And Other Items [Member] \| 2017 Credit Agreement [member]
Disclosure of detailed information about financial instruments [line items]
Net foreign exchange gain (loss)		$ 15
Foreign exchange forwards related to forecasted transactions [member] \| Electric Energy [member]
Disclosure of detailed information about financial instruments [line items]
Net foreign exchange loss				$ 6
DollarEuro Foreign Exchange Forward Contracts [Member] \| April 2024 Notes [Member]
Disclosure of detailed information about financial instruments [line items]
Borrowings, interest rate		4.625%
British PoundEuro Foreign Exchange Forward Contracts [Member]
Disclosure of detailed information about financial instruments [line items]
Derivative financial instrument, Notional amount		$ 186
British PoundEuro Foreign Exchange Forward Contracts [Member] \| Financial Income And Other Items [Member]
Disclosure of detailed information about financial instruments [line items]
Gain (loss) due to changes in estimated fair value		$ 9