v3.5.0.2
Document and Entity Information - shares
9 Months Ended
Sep. 30, 2016
Oct. 28, 2016
Entity Information [Line Items]    
Entity Voluntary Filers No  
Entity Registrant Name CROWN CASTLE INTERNATIONAL CORP  
Entity Central Index Key 0001051470  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Document Type 10-Q  
Document Period End Date Sep. 30, 2016  
Document Fiscal Year Focus 2016  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Entity Common Stock, Shares Outstanding   338,916,436
Entity Current Reporting Status Yes