Acquisitions and investments in joint ventures.

No definition available.

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Namespace Prefix:	cx_
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Balance Type:	debit
Period Type:	duration

- Definition

Bank indebtedness.

+ References

No definition available.

+ Details

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Namespace Prefix:	cx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Borrowing interest rate basis.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Capital expenditure.

+ References

No definition available.

+ Details

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Namespace Prefix:	cx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Leverage ratio.

+ References

No definition available.

+ Details

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Namespace Prefix:	cx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The adjustment to the basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 7
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_7&doctype=Standard
-URIDate 2018-03-16

+ Details

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Period Type:	instant

- Definition

The interest rate on borrowings. [Refer: Borrowings]

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of instruments representing indebtedness held by the entity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard
-URIDate 2018-03-16

+ Details

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

- 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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Financial Instruments - Additional Information - Credit Agreement, Facilities Agreement and Financing Agreement (Detail) € in Millions, £ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 EUR (€)	Dec. 31, 2018 GBP (£)	Dec. 31, 2017 EUR (€)	Dec. 31, 2017 GBP (£)	Jul. 19, 2017 USD ($)
Disclosure of detailed information about financial instruments [line items]
Maximum capital expenditure	$ 1,000	$ 1,000	$ 1,000
Acquisitions and investments in joint ventures	$ 400	$ 400	$ 400
Leverage Ratio	384.00%	385.00%	422.00%	384.00%	384.00%	385.00%	385.00%
CEMEX Holdings Philippines, Inc. [member]
Disclosure of detailed information about financial instruments [line items]
Maximum capital expenditure	$ 500	$ 500	$ 500
CEMEX Latam Holdings, S.A [member]
Disclosure of detailed information about financial instruments [line items]
Maximum capital expenditure	$ 500	$ 500	$ 500
Euro [member]
Disclosure of detailed information about financial instruments [line items]
Interest rate	3.30%	3.50%		3.30%	3.30%	3.50%	3.50%
Pounds [member]
Disclosure of detailed information about financial instruments [line items]
Interest rate	2.90%	2.60%		2.90%	2.90%	2.60%	2.60%
Credit agreement [member]
Disclosure of detailed information about financial instruments [line items]
Credit agreement amount	$ 2,746	$ 2,746
Credit agreement [member] \| Revolving Credit Facility [member]
Disclosure of detailed information about financial instruments [line items]
Credit agreement amount	$ 1,135	1,135
Credit agreement [member] \| Euro [member]
Disclosure of detailed information about financial instruments [line items]
Credit agreement amount \| €				€ 741		€ 741
Credit agreement [member] \| Pounds [member]
Disclosure of detailed information about financial instruments [line items]
Credit agreement amount \| £					£ 344		£ 344
2017 Credit Agreement [member]
Disclosure of detailed information about financial instruments [line items]
Bank indebtedness		4,050						$ 4,050
2014 Credit Agreement [member]
Disclosure of detailed information about financial instruments [line items]
Bank indebtedness		$ 3,680
Less than or equal to 4.0 ratio [Member]
Disclosure of detailed information about financial instruments [line items]
Leverage Ratio	400.00%			400.00%	400.00%
Less Than Or Equal To 3.75 Ratio [Member]
Disclosure of detailed information about financial instruments [line items]
Leverage Ratio	375.00%			375.00%	375.00%
Bottom of range [member] \| Credit agreement [member]
Disclosure of detailed information about financial instruments [line items]
Interest rate	0.75%			0.75%	0.75%
Debt instrument basis point	1.25%			1.25%	1.25%
Bottom of range [member] \| 2017 Credit Agreement [member]
Disclosure of detailed information about financial instruments [line items]
Interest rate basis		0.0125
Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Leverage Ratio	375.00%			375.00%	375.00%
Top of range [member] \| Credit agreement [member]
Disclosure of detailed information about financial instruments [line items]
Interest rate	8.50%			8.50%	8.50%
Debt instrument basis point	3.50%			3.50%	3.50%
Top of range [member] \| 2017 Credit Agreement [member]
Disclosure of detailed information about financial instruments [line items]
Interest rate basis		0.0350