v3.8.0.1
Document and Entity Information
12 Months Ended
Dec. 31, 2017
shares
Document Information [Line Items]  
Document Type 20-F
Amendment Flag false
Document Period End Date Dec. 31, 2017
Document Fiscal Year Focus 2017
Document Fiscal Period Focus FY
Trading Symbol CX
Entity Registrant Name CEMEX SAB DE CV
Entity Central Index Key 0001076378
Current Fiscal Year End Date --12-31
Entity Well-known Seasoned Issuer Yes
Entity Current Reporting Status Yes
Entity Filer Category Large Accelerated Filer
CPO [Member]  
Document Information [Line Items]  
Entity Common Stock, Shares Outstanding 15,085,567,391
Series A Shares [member]  
Document Information [Line Items]  
Entity Common Stock, Shares Outstanding 30,214,469,912
Series B Shares [member]  
Document Information [Line Items]  
Entity Common Stock, Shares Outstanding 15,107,234,956