Schedule of Long-term Debt (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2006	Oct. 31, 2009	Dec. 31, 2012	Feb. 28, 2005	Apr. 29, 2009	Jul. 01, 2009	May 06, 2008	Feb. 28, 1997
Debt Instrument [Line Items]
Total	$ 2,713	$ 2,842
Less current maturities	258	629
Less debt discount and issuance costs	21	22
Long-term debt less current maturities	2,434	2,191
Capital Lease Obligations
Debt Instrument [Line Items]
Total	199	56
5.25% Notes due 2014 | Unsecured Debt
Debt Instrument [Line Items]
Total	0	357
Interest rate stated in the debt agreement (in hundredths)	5.25%
5.75% Notes due 2016
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)			5.75%
5.75% Notes due 2016 | Unsecured Debt
Debt Instrument [Line Items]
Total	313	320
Interest rate stated in the debt agreement (in hundredths)	5.75%
5.25% Convertible Senior Notes due 2016 | AirTran Airways
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)				5.25%
5.25% Convertible Senior Notes due 2016 | Convertible Debt
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)	5.25%	5.25%			5.25%
5.25% Convertible Senior Notes due 2016 | Convertible Debt | AirTran Airways
Debt Instrument [Line Items]
Total	113	115
Interest rate stated in the debt agreement (in hundredths)	5.25%
5.125% Notes due 2017
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)						5.125%
5.125% Notes due 2017 | Unsecured Debt
Debt Instrument [Line Items]
Total	316	322
Interest rate stated in the debt agreement (in hundredths)	5.125%
Fixed-rate 717 Aircraft Notes payable through 2017 - 10.37% | Enhanced Equipment Trust Certificate | AirTran Airways
Debt Instrument [Line Items]
Total	0	41
Interest rate stated in the debt agreement (in hundredths)	10.37%
French Credit Agreements due 2018 - 1.06% | Notes Payable to Banks
Debt Instrument [Line Items]
Total	36	46
Interest rate stated in the debt agreement (in hundredths)	1.06%
Fixed-rate 737 Aircraft Notes payable through 2018 - 7.02% | Notes Payable to Banks | AirTran Airways
Debt Instrument [Line Items]
Total	24	30
Interest rate stated in the debt agreement (in hundredths)	7.02%
2.75% Unsecured Senior Notes Due 2019
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)	2.75%
2.75% Unsecured Senior Notes Due 2019 | Unsecured Debt
Debt Instrument [Line Items]
Total	300	0
Interest rate stated in the debt agreement (in hundredths)	2.75%
Term Loan Agreement due 2019 - 6.315%
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)							6.315%
Term Loan Agreement due 2019 - 6.315% | Notes Payable to Banks
Debt Instrument [Line Items]
Total	178	210
Interest rate stated in the debt agreement (in hundredths)	6.315%
Term Loan Agreement due 2019 - 6.84%
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)								6.84%
Term Loan Agreement due 2019 - 6.84% | Notes Payable to Banks
Debt Instrument [Line Items]
Total	73	85
Interest rate stated in the debt agreement (in hundredths)	6.84%
Term Loan Agreement due 2020 - 5.223%
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)									5.223%
Term Loan Agreement due 2020 - 5.223% | Notes Payable to Banks
Debt Instrument [Line Items]
Total	372	413
Interest rate stated in the debt agreement (in hundredths)	5.223%
Floating-rate 737 Aircraft Notes payable through 2020 | Notes Payable to Banks | AirTran Airways
Debt Instrument [Line Items]
Total	300	340
Pass Through Certificates due 2022 - 6.24% | Enhanced Equipment Trust Certificate
Debt Instrument [Line Items]
Total	355	371
Interest rate stated in the debt agreement (in hundredths)	6.24%
7.375% Debentures due 2027
Debt Instrument [Line Items]
Interest rate stated in the debt agreement (in hundredths)										7.375%
7.375% Debentures due 2027 | Unsecured Debt
Debt Instrument [Line Items]
Total	$ 134	$ 136
Interest rate stated in the debt agreement (in hundredths)	7.375%	7.375%