| Document and Entity Information | Sep. 09, 2024 |
| Document And Entity Information [Line Items] | |
| Entity Registrant Name | SOUTHWEST AIRLINES CO |
| Amendment Flag | false |
| Entity Central Index Key | 0000092380 |
| Document Type | 8-K |
| Document Period End Date | Sep. 09, 2024 |
| Entity Incorporation State Country Code | TX |
| Entity File Number | 1-7259 |
| Entity Tax Identification Number | 74-1563240 |
| Entity Address, Address Line One | P. O. Box 36611 |
| Entity Address, City or Town | Dallas |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 75235-1611 |
| City Area Code | (214) |
| Local Phone Number | 792-4000 |
| Written Communications | false |
| Soliciting Material | true |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock 1.00 Par Value 2 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Common Stock ($1.00 par value) |
| Trading Symbol | LUV |
| Security Exchange Name | NYSE |
| Common Stock Purchase Rights 1 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Common Stock Purchase Rights |
| Security Exchange Name | NYSE |
