Document and Entity Information
Oct. 29, 2019
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date Oct. 29, 2019
Entity Registrant Name Kirby Corporation
Entity Incorporation, State or Country Code NV
Entity File Number 1-07615
Entity Tax Identification Number 74-1884980
Entity Address, Address Line One 55 Waugh Drive
Entity Address, Address Line Two Suite 1000
Entity Address, City or Town Houston
Entity Address, State or Province TX
Entity Address, Postal Zip Code 77007
City Area Code 713
Local Phone Number 435-1000
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Entity Central Index Key 0000056047
Title of 12(b) Security Common Stock
Trading Symbol KEX
Security Exchange Name NYSE