Document And Entity Information	3 Months Ended
	Mar. 31, 2012
Document And Entity Information [Abstract]
Entity Registrant Name	Southwest Airlines Co
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0000092380
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Entity Common Stock, Shares Outstanding	767,684,913
Document Type	10-Q
Document Period End Date	Mar. 31, 2012
Amendment Flag	false
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1