XML 100 R58.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Significant Accounting Policies - Summary of Foreign Exchange Rates (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
US Dollar [member] |  |  |
Disclosure of foreign exchange rates [Line Items] |  |  |
Closing | 19.6500 | 20.7200 | 17.2300
Average | 18.8800 | 18.7200 | 15.9800
Euro [member] |  |  |
Disclosure of foreign exchange rates [Line Items] |  |  |
Closing | 23.5866 | 21.7945 | 18.7181
Average | 21.4122 | 20.6564 | 17.6041
Pounds [member] |  |  |
Disclosure of foreign exchange rates [Line Items] |  |  |
Closing | 26.5361 | 25.5361 | 25.4130
Average | 24.4977 | 25.0731 | 24.3638
Colombian Peso [member] |  |  |
Disclosure of foreign exchange rates [Line Items] |  |  |
Closing | 0.0066 | 0.0069 | 0.0055
Average | 0.0064 | 0.0062 | 0.0058
Egyptian, Pound [member] |  |  |
Disclosure of foreign exchange rates [Line Items] |  |  |
Closing | 1.1082 | 1.1234 | 2.2036
Average | 1.0620 | 1.8261 | 2.0670
Philippine pesos [member] |  |  |
Disclosure of foreign exchange rates [Line Items] |  |  |
Closing | 0.3936 | 0.4167 | 0.3661
Average | 0.3747 | 0.3927 | 0.3504

X
- Definition Disclosure of foreign exchange rates. + References No definition available. + Details
Name: | cx_DisclosureOfForeignExchangeRatesLineItems
Namespace Prefix: | cx_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The average exchange rate used by the entity. Exchange rate is the ratio of exchange for two currencies. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_AverageForeignExchangeRate
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition 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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_ClosingForeignExchangeRate
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_CurrencyAxis=currency_USD
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CurrencyAxis=currency_EUR
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CurrencyAxis=currency_GBP
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CurrencyAxis=currency_COP
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CurrencyAxis=currency_EGP
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CurrencyAxis=currency_PHP
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |