LONG-TERM DEBT (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 Mortgages	Dec. 31, 2010
Notes to Financial Statements [Abstract]
Net book value of assets pledged as collateral for the company's secured borrowings, primarily aircraft and engines	$ 2,600
Line Of Credit, Amount Terminated	100
Debt assumed in aquisition	1,100
Debt Instrument [Line Items]
Less current maturities	644	505
Long-term debt	3,107	2,875
Less debt discount and issuance costs	26	28
Line Of Credit, Amount Terminated	100
Letters of Credit Outstanding, Amount	230
Maximum additional number of assets pledged as collateral in case obligations related to fuel derivatives exceed certain thresholds	49
Long-term Debt, by Maturity [Abstract]
Long Term Debt And Capital Lease Maturities Repayments Of Principal In Year One After Current Year	627
Long-term Debt, Maturities, Repayments of Principal in Year Two	188
Long-term Debt, Maturities, Repayments of Principal in Year Three	537
Long-term Debt, Maturities, Repayments of Principal in Year Four	207
Long-term Debt, Maturities, Repayments of Principal in Year Five	550
Long-term Debt, Maturities, Repayments of Principal after Year Five	1,500
5.5% Convertible Debt due 2015 [Member]
Debt Instrument [Line Items]
Face amount of debt	70
Latest maturity date	2015
Interest rate stated in the debt agreement (in hundredths)	5.50%
Shares issued for conversions of debt	6,200,000
Cash paid for conversions of debt	73
7.0% Convertible Debt Due 2023 [Member]
Debt Instrument [Line Items]
Face amount of debt	5
Latest maturity date	2023
Interest rate stated in the debt agreement (in hundredths)	7.00%
Capital Lease Obligations (Note 8) [Member]
Debt Instrument [Line Items]
Carrying amount of debt	40	0
Term Loan Agreement due 2019 6.84% [Member]
Debt Instrument [Line Items]
Issuance date of debt	July 1, 2009
Collateral to secure loan	The loan is secured by mortgages on five of the company's 737-700 aircraft.
Face amount of debt	124
Carrying amount of debt	106	115
Number of mortgages on secured aircraft	5
Maturity date of debt	Jul. 01, 2019
Date of first required payment according to terms of debt agreement	January 1, 2010
Interest rate stated in the debt agreement (in hundredths)	6.84%
Term Loan Agreement due 2019 6.315% [Member]
Debt Instrument [Line Items]
Issuance date of debt	April 29, 2009
Collateral to secure loan	The loan is secured by mortgages on 14 of the company's 737-700 aircraft.
Face amount of debt	332
Carrying amount of debt	269	296
Number of mortgages on secured aircraft	14
Maturity date of debt	May 06, 2019
Date of first required payment according to terms of debt agreement	August 6, 2009
Interest rate stated in debt agreement (with LIBO)	LIBO rate plus 3.30%
Derivative, Fixed Interest Rate	6.315%
10.5% Notes due 2011 [Member]
Debt Instrument [Line Items]
Issuance date of debt	December 30, 2008
Collateral to secure loan	The notes are secured by a first priority perfected security interest in a specified pool of 17 Boeing 737-700 aircraft granted under a single mortgage.
Face amount of debt	400
Carrying amount of debt	0	404
Number of mortgages on secured aircraft	1
Maturity date of debt	Dec. 15, 2011
Interest rate stated in the debt agreement (in hundredths)	10.50%
Term Loan Agreement due 2020-5.223% [Member]
Debt Instrument [Line Items]
Issuance date of debt	May 6, 2008
Collateral to secure loan	The loan is secured by first mortgages on 21 of the company's 737-700 aircraft.
Face amount of debt	600
Carrying amount of debt	487	522
Number of mortgages on secured aircraft	21
Maturity date of debt	May 09, 2020
Date of first required payment according to terms of debt agreement	August 9, 2008
Interest rate stated in debt agreement (with LIBO)	LIBO rate plus .95%
Derivative, Fixed Interest Rate	5.223%
Pass Through Certificates [Member]
Debt Instrument [Line Items]
Issuance date of debt	October 3, 2007
Collateral to secure loan	The equipment notes are secured by mortgages on 16 of the company's 737-700 aircraft.
Face amount of debt	500
Carrying amount of debt	411	428
Number of mortgages on secured aircraft	16
Maturity date of debt	Aug. 01, 2022
Date of first required payment according to terms of debt agreement	February 1, 2008
Amount Paid to Hedge The Variability of Interest Rates	20
Pass Through Certificates Series A [Member]
Debt Instrument [Line Items]
Face amount of debt	412
Interest rate stated in the debt agreement (in hundredths)	6.15%
Pass Through Certificates Series B [Member]
Debt Instrument [Line Items]
Face amount of debt	88
Interest rate stated in the debt agreement (in hundredths)	6.65%
French Credit Agreements due 2018 [Member]
Debt Instrument [Line Items]
Issuance date of debt	Fourth Quarter 2004
Collateral to secure loan	The company pledged 4 aircraft as collateral for the loans.
Face amount of debt	112
Carrying amount of debt	64	73
Number of mortgages on secured aircraft	4
Latest maturity date	2018
Effective economic yield	Libor minus 45 basis points
Number Of Identical Floating Rate Financing Agreements Entered Into Concurrently With French Banking Partnerships	4
Term Of Floating Rate Financing Agreement	13 years
French Credit Agreements due 2012 [Member]
Debt Instrument [Line Items]
Issuance date of debt	4th Quarter 1999
Collateral to secure loan	The company pledged 2 aircraft as collateral for the loans.
Face amount of debt	56
Carrying amount of debt	7	14
Number of mortgages on secured aircraft	2
Latest maturity date	2012
Effective economic yield	Libor minus 67 basis points
Number Of Identical Floating Rate Financing Agreements Entered Into Concurrently With French Banking Partnerships	2
Term Of Floating Rate Financing Agreement	13 years
5.75% Notes due 2016 [Member]
Debt Instrument [Line Items]
Issuance date of debt	December 1, 2006
Face amount of debt	300
Carrying amount of debt	329	309
Maturity date of debt	Dec. 31, 2016
Date of first required payment according to terms of debt agreement	June 15, 2007
Interest rate stated in the debt agreement (in hundredths)	5.75%
Average floating rate recognized	2.77%
5.125% Notes due 2017 [Member]
Debt Instrument [Line Items]
Issuance date of debt	February 1, 2005
Face amount of debt	300
Carrying amount of debt	336	345
Maturity date of debt	Dec. 31, 2017
Date of first required payment according to terms of debt agreement	September 1, 2005
Interest rate stated in the debt agreement (in hundredths)	5.125%
5.25% Notes due 2014 [Member]
Debt Instrument [Line Items]
Issuance date of debt	September 1, 2004
Face amount of debt	350
Carrying amount of debt	375	385
Maturity date of debt	Dec. 31, 2014
Interest rate stated in the debt agreement (in hundredths)	5.25%
6.5% Notes due 2012 [Member]
Debt Instrument [Line Items]
Issuance date of debt	March 1, 2002
Face amount of debt	385
Carrying amount of debt	387	400
Maturity date of debt	Mar. 01, 2012
Interest rate stated in the debt agreement (in hundredths)	6.50%
Average floating rate recognized	2.91%
Unsecured Senior Notes Due 2027 [Member]
Debt Instrument [Line Items]
Issuance date of debt	February 28, 1997
Face amount of debt	100
Carrying amount of debt	135	117
Maturity date of debt	Mar. 01, 2027
Interest rate stated in the debt agreement (in hundredths)	7.375%
Average floating rate recognized	2.36%
The number of basis points treasury rate is adjusted in a debenture redemption option	20
Southwest Airlines Co. [Member] | 5.25% Convertible Senior Notes Due 2016 [Member]
Debt Instrument [Line Items]
Conversion ratio	0.0527157
Conversion Price	$ 0.61516
Cash set aside for conversion	68
AirTran Airways [Member] | Floating-rate 737 aircraft notes payable through 2020 [Member]
Debt Instrument [Line Items]
Collateral to secure loan	note is secured by a first mortgage on the aircraft to which it relates
Carrying amount of debt	604	0
Number of mortgages on secured aircraft	27
Earliest maturity date	2016
Latest maturity date	2020
Weighted average interest rate	1.91%
AirTran Airways [Member] | Fixed-rate 737 aircraft notes payable through 2018 [Member]
Debt Instrument [Line Items]
Carrying amount of debt	42	0
Number of mortgages on secured aircraft	3
Earliest maturity date	2016
Latest maturity date	2018
Weighted average interest rate	7.02%
AirTran Airways [Member] | Fixed-rate 717 aircraft notes payable through 2017 [Member]
Debt Instrument [Line Items]
Collateral to secure loan	8 B717 aircraft
Carrying amount of debt	67	0
Latest maturity date	2017
Weighted average interest rate	10.38%
AirTran Airways [Member] | 5.25% Convertible Senior Notes Due 2016 [Member]
Debt Instrument [Line Items]
Issuance date of debt	October 2009
Face amount of debt	115
Carrying amount of debt	118	0
Interest rate stated in the debt agreement (in hundredths)	5.25%
Conversion ratio	0.1642233
Extinguishment of Debt, Amount	5
Conversion option, amount	35
Debt Instrument, Unamortized Premium	$ 10
Repurchase price percentage	100.00%