| Document and Entity Information | Apr. 25, 2024 |
| Cover [Abstract] | |
| Entity Registrant Name | KIRBY CORPORATION |
| Entity Central Index Key | 0000056047 |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Amendment Description | Kirby Corporation (the “Company”) is filing this Amendment No. 1 on Form 8-K/A to amend the Current Report on Form 8-K, as initially filed with the Securities and Exchange Commission on April 25, 2024 (the “Initial Form 8-K”), solely to provide certain information called for under Item 5.02(e) that was not previously filed with the Initial Form 8‑K as it was not determined at the time of filing. Except as provided herein, the disclosures in the Initial Form 8-K remain unchanged. |
| Document Period End Date | Apr. 25, 2024 |
| Securities Act File Number | 1-7615 |
| Entity Incorporation, State or Country Code | NV |
| 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 |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | KEX |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
