v2.4.0.6
Document and Entity Information (USD $)
12 Months Ended
Dec. 31, 2012
Feb. 22, 2013
Document and Entity Information [Abstract]    
Entity Registrant Name KIRBY CORP  
Entity Central Index Key 0000056047  
Current Fiscal Year End Date --12-31  
Entity Well-known Seasoned Issuer Yes  
Entity Voluntary Filers No  
Entity Current Reporting Status Yes  
Entity Filer Category Large Accelerated Filer  
Entity Public Float $ 0  
Entity Common Stock, Shares Outstanding   56,719,000
Document Fiscal Year Focus 2012  
Document Fiscal Period Focus FY  
Document Type 10-K  
Amendment Flag false  
Document Period End Date Dec. 31, 2012