Southwest Airlines (LUV) 10-Q 29 Oct 15 2015 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 27, 2015
Entity Information [Line Items]
Entity Registrant Name	SOUTHWEST AIRLINES CO
Entity Central Index Key	92,380
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		650,355,108

Condensed Consolidated Balance

Condensed Consolidated Balance Sheet - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 1,740	$ 1,282
Short-term investments	1,356	1,706
Accounts and other receivables	465	365
Inventories of parts and supplies, at cost	308	342
Deferred income taxes	465	477
Prepaid expenses and other current assets	239	232
Total current assets	4,573	4,404
Property and equipment, at cost:
Flight equipment	19,244	18,473
Ground property and equipment	3,066	2,853
Deposits on flight equipment purchase contracts	692	566
Assets constructed for others	823	621
Property and equipment, at cost	23,825	22,513
Less allowance for depreciation and amortization	8,896	8,221
Property and equipment, net	14,929	14,292
Goodwill	970	970
Other assets	687	534
Total assets	21,159	20,200
Current liabilities:
Accounts payable	1,235	1,203
Accrued liabilities	2,049	1,565
Air traffic liability	3,513	2,897
Current maturities of long-term debt	287	258
Total current liabilities	7,084	5,923
Long-term debt less current maturities	2,381	2,434
Deferred income taxes	3,111	3,259
Construction obligation	684	554
Other noncurrent liabilities	931	1,255
Stockholders' equity:
Common stock	808	808
Capital in excess of par value	1,330	1,315
Retained earnings	8,922	7,416
Accumulated other comprehensive loss	(903)	(738)
Treasury stock, at cost	(3,189)	(2,026)
Total stockholders' equity	6,968	6,775
Total liabilities and stockholders' equity	$ 21,159	$ 20,200

Condensed Consolidated Statemen

Condensed Consolidated Statement of Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
OPERATING REVENUES:
Passenger	$ 4,716	$ 4,564	$ 13,746	$ 13,249
Freight	44	45	134	128
Special revenue adjustment	172	0	172	0
Other	386	191	791	600
Total operating revenues	5,318	4,800	14,843	13,977
OPERATING EXPENSES:
Salaries, wages, and benefits	1,699	1,363	4,725	4,044
Fuel and oil	936	1,386	2,818	4,125
Maintenance materials and repairs	259	248	729	734
Aircraft rentals	60	71	179	227
Landing fees and other rentals	303	289	887	849
Depreciation and amortization	258	238	751	687
Acquisition and integration	6	23	32	78
Other operating expenses	572	568	1,632	1,628
Total operating expenses	4,093	4,186	11,753	12,372
OPERATING INCOME	1,225	614	3,090	1,605
OTHER EXPENSES (INCOME):
Interest expense	31	31	92	97
Capitalized interest	(9)	(6)	(23)	(18)
Interest income	(2)	(2)	(5)	(5)
Other (gains) losses, net	272	66	394	16
Total other expenses (income)	292	89	458	90
INCOME BEFORE INCOME TAXES	933	525	2,632	1,515
PROVISION FOR INCOME TAXES	349	196	987	569
NET INCOME	$ 584	$ 329	$ 1,645	$ 946
NET INCOME PER SHARE, BASIC	$ 0.89	$ 0.48	$ 2.47	$ 1.37
NET INCOME PER SHARE, DILUTED	$ 0.88	$ 0.48	$ 2.45	$ 1.36
COMPREHENSIVE INCOME	$ 345	$ 126	$ 1,480	$ 857
BASIC WEIGHTED AVERAGE SHARES OUTSTANDING
Basic	655	683	665	690
DILUTED WEIGHTED AVERAGE SHARES OUTSTANDING
Diluted	663	691	673	699
Cash dividends declared per common share	$ 0.075	$ 0.060	$ 0.210	$ 0.160

Condensed Consolidated Stateme4

Condensed Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 584	$ 329	$ 1,645	$ 946
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Depreciation and amortization	258	238	751	687
Unrealized/realized (gain) loss on fuel derivative instruments	87	63	172	(4)
Deferred income taxes	(82)	392	(40)	472
Changes in certain assets and liabilities:
Accounts and other receivables	4	(22)	(86)	(83)
Other assets	33	6	40	(7)
Accounts payable and accrued liabilities	380	(534)	424	(86)
Air traffic liability	(301)	(108)	617	806
Cash collateral received from (provided to) derivative counterparties	181	(98)	(213)	8
Other, net	(308)	(26)	(396)	(41)
Net cash provided by operating activities	836	240	2,914	2,698
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(230)	(406)	(1,231)	(1,282)
Assets constructed for others	(32)	(27)	(76)	(58)
Purchases of short-term investments	(506)	(415)	(1,383)	(2,344)
Proceeds from sales of short-term and other investments	509	805	1,732	2,427
Payments for (Proceeds from) Other Investing Activities	0	(1)	(9)	(2)
Net cash used in investing activities	(259)	(44)	(967)	(1,259)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from Employee stock plans	9	23	30	96
Proceeds from termination of interest rate derivative instruments	0	0	12	0
Reimbursement for assets constructed for others	9	26	14	26
Payments of long-term debt and capital lease obligations	(79)	(48)	(170)	(167)
Payments of cash dividends	(49)	(41)	(180)	(138)
Repayment of construction obligation	(3)	(3)	(8)	(8)
Repurchase of common stock	(500)	(200)	(1,180)	(755)
Other, net	4	(3)	(7)	(16)
Net cash used in financing activities	(609)	(246)	(1,489)	(962)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(32)	(50)	458	477
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	1,772	1,882	1,282	1,355
CASH AND CASH EQUIVALENTS AT END OF PERIOD	1,740	1,832	1,740	1,832
CASH PAYMENTS FOR:
Interest, net of amount capitalized	33	35	86	102
Income taxes	409	132	975	144
SUPPLEMENTAL DISCLOSURE OF NONCASH TRANSACTIONS
Flight equipment under capital leases	48	31	130	94
Assets constructed for others	$ 46	$ 27	$ 126	$ 59

BASIS OF PRESENTATION

BASIS OF PRESENTATION	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
BASIS OF PRESENTATION	BASIS OF PRESENTATION Southwest Airlines Co. (the “Company”) operates Southwest Airlines, a major passenger airline that provides scheduled air transportation in the United States and near-international markets. The unaudited Condensed Consolidated Financial Statements include accounts of the Company and its wholly owned subsidiaries, which include AirTran Holdings, LLC, the parent company of AirTran Airways, Inc. (“AirTran Airways”). On May 2, 2011 (the “acquisition date”), the Company acquired all of the outstanding equity of AirTran Holdings, Inc. (“AirTran Holdings”), the former parent company of AirTran Airways. Throughout this Form 10-Q, the Company makes reference to AirTran, which is meant to be inclusive of the following: (i) for periods prior to the acquisition date, AirTran Holdings and its subsidiaries, including, among others, AirTran Airways; and (ii) for periods on and after the acquisition date, AirTran Holdings, LLC, the successor to AirTran Holdings, and its subsidiaries, including among others, AirTran Airways. AirTran's final passenger service was on December 28, 2014. Although the vast majority of integration costs were incurred in periods prior to 2015, the Company continues to incur costs associated with the integration of AirTran, and those costs are included in Acquisition and integration costs in the accompanying unaudited Condensed Consolidated Statement of Comprehensive Income. The accompanying unaudited Condensed Consolidated Financial Statements of the Company and its subsidiaries have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles in the United States (“GAAP”) for complete financial statements. The unaudited Condensed Consolidated Financial Statements for the interim periods ended September 30, 2015 and 2014 include all adjustments which are, in the opinion of management, necessary for a fair presentation of the results for the interim periods. This includes all normal and recurring adjustments and elimination of significant intercompany transactions. Financial results for the Company and airlines in general can be seasonal in nature. In many years, the Company's revenues, as well as its operating income and net income, have been better in its second and third fiscal quarters than in its first and fourth fiscal quarters. Air travel is also significantly impacted by general economic conditions, the amount of disposable income available to consumers, unemployment levels, corporate travel budgets, and other factors beyond the Company's control. These and other factors, such as the price of jet fuel in some periods, the nature of the Company's fuel hedging program, the periodic volatility of commodities used by the Company for hedging jet fuel, and the requirements related to hedge accounting, have created, and may continue to create, significant volatility in the Company's financial results. See Note 3 for further information on fuel and the Company's hedging program. Operating results for the three and nine months ended September 30, 2015 , are not necessarily indicative of the results that may be expected for future quarters or for the year ended December 31, 2015 . For further information, refer to the Consolidated Financial Statements and footnotes thereto included in the Southwest Airlines Co. Annual Report on Form 10-K for the year ended December 31, 2014 .

CHANGES IN ACCOUNTING OR ESTIMA

CHANGES IN ACCOUNTING OR ESTIMATES AND NEW ACCOUNTING PRONOUNCEMENTS	9 Months Ended
	Sep. 30, 2015
Change in Accounting Estimate [Abstract]
CHANGES IN ACCOUNTING OR ESTIMATES AND NEW ACCOUNTING PRONOUNCEMENTS	CHANGES IN ACCOUNTING OR ESTIMATES AND NEW ACCOUNTING PRONOUNCEMENTS New accounting pronouncements On February 18, 2015, the Financial Accounting Standards Board ("FASB") and the International Accounting Standards Board issued a final standard that amends the current consolidation guidance. The standard amends both the variable interest entity and voting interest entity consolidation models. The standard is effective for public reporting entities in fiscal periods beginning after December 15, 2015, and early adoption is permitted. Once adopted, the Company will need to assess the potential for entity consolidation under a new consolidation model; however, the Company does not believe this will result in changes to its previous consolidation conclusions. The Company will adopt this new standard during first quarter 2016 , but does not expect it to have a significant impact. On May 28, 2014, the FASB issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers. Following the FASB's finalization of a one year deferral of this standard, the ASU is now effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2017, with early adoption permitted for fiscal years, and interim periods within those years, beginning on or after December 15, 2016. The Company believes the most significant impact of this ASU on its accounting will be the elimination of the incremental cost method for frequent flyer accounting, which will require the Company to re-value its liability earned by Customers associated with flight points with a relative fair value approach. The Company is continuing to evaluate the new guidance and plans to provide additional information about its expected financial impact at a future date. Changes in accounting or estimates During July 2015, the Company executed an amended co-branded credit card agreement (“Agreement”) with Chase Bank USA, N.A. (“Chase”), through which the Company sells loyalty points and other items to Chase. The Company's Rapid Rewards program members ("Members") are able to accrue loyalty points based on purchases using the Chase co-branded Southwest Visa credit card. The Agreement materially modifies the previously existing agreement between Chase and the Company. Consideration received as part of this Agreement is subject to ASU 2009-13, "Multiple-Deliverable Revenue Arrangements - a consensus of the FASB Emerging Issues Task Force". Historically, funds received from the sale of points associated with these agreements were accounted for under the residual method. Under the residual method, the Company estimated the portion from frequent flyer points sold associated with Southwest’s co-branded Chase Visa credit card that related to free travel. The estimated amounts associated with free travel were deferred and recognized as Passenger revenue when the ultimate free travel awards were flown. Under the residual method, the Company estimated that 100 percent of the amount received from frequent flyer points sold were related to free travel. The modified Agreement has the following multiple elements: travel points to be awarded; use of the Southwest Airlines’ brand and access to Rapid Reward Member lists; advertising elements; and the Company’s resource team. Under ASU 2009-13, these deliverables are accounted for separately, and allocation of consideration from the Agreement is determined based on the relative stand-alone selling price of each deliverable. As compared to the residual method, the application of ASU 2009-13 to the Agreement decreases the relative value of the air transportation deliverables that the Company records as deferred revenue (and ultimately Passenger revenues when redeemed awards are flown) and increases the relative value of the marketing-related deliverables recorded in Other revenues at the time these marketing-related deliverables are provided. Significant management judgment was used to estimate the stand-alone selling price of each of the deliverables. The Company determined the best estimate of selling price by considering multiple inputs and methods including, but not limited to, the estimated selling price of comparable travel, discounted cash flows, brand value, published selling prices, number of points awarded, and the number of points redeemed. The Company estimated the selling prices and volumes over the term of the Agreement in order to determine the allocation of proceeds to each of the multiple deliverables. The Company records Passenger revenue related to (i) air transportation and (ii) certificates for discounted companion travel when the transportation is delivered. The other elements are recognized as Other - net revenue when earned. The Company followed the transition approach of ASU 2009-13, which required that the Company's existing deferred revenue balance, classified within Air traffic liability, be adjusted to reflect the value, on a relative selling price basis, of any undelivered element remaining at the date of contract modification. The relative selling price of the undelivered element (air transportation) is lower than the rate at which it had been deferred under the previous contract and the Company recorded a one-time, non-cash adjustment to decrease frequent flyer deferred revenue and increase Special revenue adjustment. In addition, the Agreement and the resulting application of ASU 2009-13 are expected to result in an acceleration of the timing of Operating revenues on a prospective basis relative to the Company's previous application of the residual method due to assigning a higher value to the non-transportation elements of the Agreement than under the residual method. The impacts on revenue and earnings from this change in accounting principle are as follows: (in millions, except per share amounts) Three months ended September 30, 2015 Nine months ended September 30, 2015 Passenger revenue $ (40 ) $ (40 ) Special revenue adjustment 172 172 Other revenue 171 171 Operating revenues $ 303 $ 303 Net income $ 161 $ 161 Net income per basic share $ 0.25 $ 0.24 Net income per diluted share $ 0.24 $ 0.24 During fourth quarter 2014, the Company increased the amount of spoilage recorded associated with frequent flyer points sold to business partners as a result of continued monitoring of Member redemption activity and behavior under its Rapid Rewards program. Based on a sufficient amount of historical data and Member attributes observed since the new program was launched in 2011, the Company developed a predictive statistical model to analyze the amount of spoilage expected. In estimating spoilage, the Company takes into account the Member’s past behavior, as well as several factors that are expected to be indicative of the likelihood of future point redemption. These factors include, but are not limited to, tenure with program, points accrued in the program, and whether or not the Customer has a co-branded credit card. This change in estimate was recorded on a prospective basis, effective October 1, 2014. As a result of its annual update the Company will prospectively apply a slight decrease in the rate beginning as of October 1, 2015; however, the precise revenue impact will not be determinable until the actual number of point redemptions for the period is known. The Company will continue to monitor all factors that influence spoilage and Member behavior in order to determine its best estimate of expected spoilage. The impacts on revenue and earnings for the lower rate applied in fourth quarter 2014 are as follows: (in millions, except per share amounts) Three months ended September 30, 2015 Nine months ended September 30, 2015 Passenger revenue $ 30 $ 115 Net income $ 16 $ 61 Net income per basic share $ 0.02 $ 0.09 Net income per diluted share $ 0.02 $ 0.09

FINANCIAL DERIVATIVE INSTRUMENT

FINANCIAL DERIVATIVE INSTRUMENTS	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
FINANCIAL DERIVATIVE INSTRUMENTS	(500)(e) (225) to (275)(e) (75) to (150) or >(550)(e) (g) (g) If credit rating is investment grade, fair value of fuel derivative level at which: Cash is provided to CP (50) to (200) or >(600) (50) to (100) or >(500) >(125) (75) to (150) or >(550) >(125) >(50) Cash is received from CP >50 >150 >175(c) >250 >75 >50 Aircraft or cash can be pledged to CP as collateral (200) to (600)(f) (100) to (500)(d) N/A (150) to (550)(d) N/A N/A If credit rating is non-investment grade, fair value of fuel derivative level at which: Cash is provided to CP (0) to (200) or >(600) (0) to (100) or >(500) (b) (0) to (150) or >(550) (b) (b) Cash is received from CP (b) (b) (b) (b) (b) (b) Aircraft or cash can be pledged to CP as collateral (200) to (600) (100) to (500) N/A (150) to (550) N/A N/A (a) Individual counterparties with fair value of fuel derivatives < $30 million . (b) Cash collateral is provided at 100 percent of fair value of fuel derivative contracts. (c) Thresholds may vary based on changes in credit ratings within investment grade. (d) The Company has the option of providing cash, letters of credit, or pledging aircraft as collateral. (e) The Company has the option of providing cash or letters of credit as collateral. (f) The Company has the option of providing cash or pledging aircraft as collateral. (g) The Company has the option to substitute letters of credit for 100 percent of cash collateral requirement. (h) The Company has the option of providing letters of credit in addition to aircraft collateral if the appraised value of the aircraft does not meet the collateral requirements." id="sjs-B4">FINANCIAL DERIVATIVE INSTRUMENTS Fuel contracts Airline operators are inherently dependent upon energy to operate and, therefore, are impacted by changes in jet fuel prices. Furthermore, jet fuel and oil typically represent one of the largest operating expenses for airlines. The Company endeavors to acquire jet fuel at the lowest possible cost and to reduce volatility in operating expenses through its fuel hedging program. Although the Company may periodically enter into jet fuel derivatives for short-term timeframes, because jet fuel is not widely traded on an organized futures exchange, there are limited opportunities to hedge directly in jet fuel for time horizons longer than approximately 24 months into the future. However, the Company has found that financial derivative instruments in other commodities, such as West Texas Intermediate (“WTI”) crude oil, Brent crude oil, and refined products, such as heating oil and unleaded gasoline, can be useful in decreasing its exposure to jet fuel price volatility. The Company does not purchase or hold any financial derivative instruments for trading or speculative purposes. The Company has used financial derivative instruments for both short-term and long-term time frames and primarily uses a mixture of purchased call options, collar structures (which include both a purchased call option and a sold put option), call spreads (which include a purchased call option and a sold call option), put spreads (which include a purchased put option and a sold put option), and fixed price swap agreements in its portfolio. Although the use of collar structures and swap agreements can reduce the overall cost of hedging, these instruments carry more risk than purchased call options in that the Company could end up in a liability position when the collar structure or swap agreement settles. With the use of purchased call options and call spreads, the Company cannot be in a liability position at settlement, but does not have coverage once market prices fall below the strike price of the purchased call option. The Company evaluates its hedge volumes strictly from an “economic” standpoint and thus does not consider whether the hedges have qualified or will qualify for hedge accounting. The Company defines its “economic” hedge as the net volume of fuel derivative contracts held, including the impact of positions that have been offset through sold positions, regardless of whether those contracts qualify for hedge accounting. The level at which the Company is economically hedged for a particular period is also dependent on current market prices for that period, as well as the types of derivative instruments held and the strike prices of those instruments. For example, the Company may enter into “out-of-the-money” option contracts (including catastrophic protection), which may not generate intrinsic gains at settlement if market prices do not rise above the option strike price. Therefore, even though the Company may have an “economic” hedge in place for a particular period, that hedge may not produce any hedging gains at settlement and may even produce hedging losses depending on market prices, the types of instruments held, and the strike prices of those instruments. For the three months ended September 30, 2015 , the Company had fuel derivative instruments that settled. Although a portion of these instruments finished "out of the money" and did not result in a payment to or from the counterparty at settlement, the instruments in place could have represented an "economic" hedge for up to 43 percent of its fuel consumption if prices had increased to significantly higher levels. During third quarter 2015, t he Company reduced its hedge position related to future periods. This reduction in the Company's hedge position primarily was accomplished through entering into offsetting derivatives that will also settle in the same periods as the economic hedge derivative. Prior to third quarter 2015, the Company had paid $39 million to counterparties to purchase offsetting derivatives that also settled during third quarter 2015. These transactions are reflected in the total economic fuel hedge settlement losses of $245 million recognized in Fuel and oil expense during third quarter 2015. The Company also paid $294 million to counterparties during third quarter 2015 to purchase offsetting derivatives that will settle in fourth quarter 2015 and first half 2016. Therefore, as of September 30, 2015 , the Company no longer had an "economic" hedge in place for its remaining 2015 estimated fuel consumption. However, in periods prior to third quarter, the Company did have fourth quarter 2015 hedges in place that were subsequently offset. The following table provides information about the Company’s volume of fuel hedging for the years 2015 through 2018 on an “economic” basis: Fuel hedged as of September 30, 2015 Derivative underlying commodity type as of Period (by year) (gallons in millions) September 30, 2015 Fourth quarter 2015 — (a) 2016 1,188 (b) Brent crude oil, Heating oil, and Gulf Coast jet fuel 2017 1,294 (b) WTI crude and Brent crude oil 2018 466 (b) Brent crude oil (a) The Company is effectively unhedged for fourth quarter 2015 at current price levels. While the Company still holds derivative contracts as of September 30, 2015 , that will settle during fourth quarter 2015, the losses associated with those contracts are substantially locked in. However, if market prices were to increase or decrease significantly related to the fourth quarter 2015 positions prior to these contracts settling, the losses incurred at settlement could be slightly lower or higher than currently expected amounts during that period. (b) Due to the types of derivatives and commodities utilized by the Company and different price levels of those contracts, this volume represents the maximum "economic" net hedge in place. The Company's average "economic" net hedge of estimated fuel consumption covered by fuel derivative contracts is lower than this maximum volume, may vary significantly as market prices fluctuate, and begins to provide hedge coverage at price levels above current market prices. Upon proper qualification, the Company accounts for its fuel derivative instruments as cash flow hedges. Generally, utilizing hedge accounting, all periodic changes in fair value of the derivatives designated as hedges that are considered to be effective are recorded in Accumulated other comprehensive income (loss) ("AOCI") until the underlying jet fuel is consumed. See Note 4 . The Company’s results are subject to the possibility that periodic changes will not be effective, as defined, or that the derivatives will no longer qualify for hedge accounting. Ineffectiveness results when the change in the fair value of the derivative instrument exceeds the change in the value of the Company’s expected future cash outlay to purchase and consume jet fuel. To the extent that the periodic changes in the fair value of the derivatives are ineffective, the ineffective portion is recorded to Other (gains) losses, net, in the unaudited Condensed Consolidated Statement of Comprehensive Income. Likewise, if a hedge ceases to qualify for hedge accounting, any change in the fair value of derivative instruments since the last reporting period is recorded to Other (gains) losses, net, in the unaudited Condensed Consolidated Statement of Comprehensive Income in the period of the change; however, any amounts previously recorded to AOCI would remain there until such time as the original forecasted transaction occurs, at which time these amounts would be reclassified to Fuel and oil expense. When the Company has sold derivative positions in order to effectively “close” or offset a derivative already held as part of its fuel derivative instrument portfolio, any subsequent changes in fair value of those positions are marked to market through earnings. Likewise, any changes in fair value of those positions that were offset by entering into the sold positions and were de-designated as hedges are concurrently marked to market through earnings. However, any changes in value related to hedges that were deferred as part of AOCI while designated as a hedge would remain until the originally forecasted transaction occurs. In a situation where it becomes probable that a fuel hedged forecasted transaction will not occur, any gains and/or losses that have been recorded to AOCI would be required to be immediately reclassified into earnings. The Company did not have any such situations occur during 2014 , or during the nine months ended September 30, 2015 . In some situations, an entire commodity type used in hedging may cease to qualify for special hedge accounting treatment. As an example, from July 2013 to July 2015, the Company's routine statistical analysis performed to determine which commodities qualified for special hedge accounting treatment on a prospective basis dictated that WTI crude oil based derivatives no longer qualified for hedge accounting. This was primarily due to the fact that the correlation between WTI crude oil prices and jet fuel prices during recent periods had not been as strong as in the past, and therefore the Company could no longer demonstrate that derivatives based on WTI crude oil prices would result in effective hedges on a prospective basis. As such, the changes in fair value of all of the Company's derivatives based in WTI were recorded directly to Other (gains) losses. The Company's routine statistical analysis performed for the three months ended September 30, 2015 , dictated that WTI crude oil based derivatives again qualified for hedge accounting. All cash flows associated with purchasing and selling fuel derivatives are classified as Other operating cash flows in the unaudited Condensed Consolidated Statement of Cash Flows. The following table presents the location of all assets and liabilities associated with the Company’s derivative instruments within the unaudited Condensed Consolidated Balance Sheet: Asset derivatives Liability derivatives Balance Sheet Fair value at Fair value at Fair value at Fair value at (in millions) location 9/30/2015 12/31/2014 9/30/2015 12/31/2014 Derivatives designated as hedges* Fuel derivative contracts (gross) Accrued liabilities $ 36 $ — $ 414 $ — Fuel derivative contracts (gross) Other noncurrent liabilities 54 — 596 643 Interest rate derivative contracts Other assets 6 13 — — Interest rate derivative contracts Other noncurrent liabilities — — 54 61 Total derivatives designated as hedges $ 96 $ 13 $ 1,064 $ 704 Derivatives not designated as hedges* Fuel derivative contracts (gross) Accrued liabilities $ 1,358 $ 1,190 $ 1,536 $ 1,432 Fuel derivative contracts (gross) Other noncurrent liabilities 282 157 414 273 Total derivatives not designated as hedges $ 1,640 $ 1,347 $ 1,950 $ 1,705 Total derivatives $ 1,736 $ 1,360 $ 3,014 $ 2,409 * Represents the position of each trade before consideration of offsetting positions with each counterparty and does not include the impact of cash collateral deposits provided to or received from counterparties. See discussion of credit risk and collateral following in this Note. In addition, the Company had the following amounts associated with fuel derivative instruments and hedging activities in its unaudited Condensed Consolidated Balance Sheet: Balance Sheet September 30, December 31, (in millions) location 2015 2014 Cash collateral deposits provided to counterparties for fuel contracts - current Offset against Accrued liabilities $ 15 $ 68 Cash collateral deposits provided to counterparties for fuel Offset against Other noncurrent liabilities 463 198 Due to third parties for fuel contracts Accounts payable 41 16 All of the Company's fuel derivative instruments and interest rate swaps are subject to agreements that follow the netting guidance in the applicable accounting standards for derivatives and hedging. The types of derivative instruments the Company has determined are subject to netting requirements in the accompanying unaudited Condensed Consolidated Balance Sheet are those in which the Company pays or receives cash for transactions with the same counterparty and in the same currency via one net payment or receipt. For cash collateral held by the Company or provided to counterparties, the Company nets such amounts against the fair value of the Company's derivative portfolio by each counterparty. The Company has elected to utilize netting for both its fuel derivative instruments and interest rate swap agreements and also classifies such amounts as either current or noncurrent, based on the net fair value position with each of the Company's counterparties in the unaudited Condensed Consolidated Balance Sheet. The Company's application of its netting policy associated with cash collateral differs depending on whether its derivative instruments are in a net asset position or a net liability position. If its fuel derivative instruments are in a net asset position with a counterparty, cash collateral amounts held are first netted against current outstanding derivative amounts associated with that counterparty until that balance is zero, and then any remainder is applied against the fair value of noncurrent outstanding derivative instruments. If the Company's fuel derivative instruments are in a net liability position with the counterparty, cash collateral amounts provided are first netted against noncurrent outstanding derivative amounts associated with that counterparty until that balance is zero, and then any remainder is applied against the fair value of current outstanding derivative instruments. The Company has the following recognized financial assets and financial liabilities resulting from those transactions that meet the scope of the disclosure requirements as necessitated by applicable accounting guidance for balance sheet offsetting: Offsetting of derivative assets (in millions) (i) (ii) (iii) = (i) + (ii) (i) (ii) (iii) = (i) + (ii) September 30, 2015 December 31, 2014 Description Balance Sheet location Gross amounts of recognized assets Gross amounts offset in the Balance Sheet Net amounts of assets presented in the Balance Sheet (a) Gross amounts of recognized assets Gross amounts offset in the Balance Sheet Net amounts of assets presented in the Balance Sheet (a) Fuel derivative contracts Accrued liabilities $ 1,409 $ (1,409 ) $ — $ 1,258 $ (1,258 ) $ — Fuel derivative contracts Other noncurrent liabilities $ 799 $ (799 ) $ — $ 355 $ (355 ) $ — Interest rate derivative contracts Other assets $ 6 $ — $ 6 $ 13 $ — $ 13 Offsetting of derivative liabilities (in millions) (i) (ii) (iii) = (i) + (ii) (i) (ii) (iii) = (i) + (ii) September 30, 2015 December 31, 2014 Description Balance Sheet location Gross amounts of recognized liabilities Gross amounts offset in the Balance Sheet Net amounts of liabilities presented in the Balance Sheet (a) Gross amounts of recognized liabilities Gross amounts offset in the Balance Sheet Net amounts of liabilities presented in the Balance Sheet (a) Fuel derivative contracts Accrued liabilities $ 1,950 $ (1,409 ) $ 541 $ 1,432 $ (1,258 ) $ 174 Fuel derivative contracts Other noncurrent liabilities $ 1,010 $ (799 ) $ 211 $ 916 $ (355 ) $ 561 Interest rate derivative contracts Other noncurrent liabilities $ 54 $ — $ 54 $ 61 $ — $ 61 (a) The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5 . The following tables present the impact of derivative instruments and their location within the unaudited Condensed Consolidated Statement of Comprehensive Income for the three and nine months ended September 30, 2015 and 2014 : Derivatives in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives (effective portion) (Gain) loss reclassified from AOCI into income (effective portion) (a) (Gain) loss recognized in income on derivatives (ineffective portion) (b) Three months ended Three months ended Three months ended September 30, September 30, September 30, (in millions) 2015 2014 2015 2014 2015 2014 Fuel derivative contracts $ 315 * $ 214 * $ 79 * $ 4 * $ — $ 11 Interest rate derivatives 3 * (2 ) * 3 * 4 * — (2 ) Total $ 318 $ 212 $ 82 $ 8 $ — $ 9 *Net of tax (a) Amounts related to fuel derivative contracts and interest rate derivatives are included in Fuel and oil and Interest expense, respectively. (b) Amounts are included in Other (gains) losses, net. Derivatives in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives (effective portion) (Gain) loss reclassified from AOCI into income (effective portion)(a) (Gain) loss recognized in income on derivatives (ineffective portion)(b) Nine months ended Nine months ended Nine months ended September 30, September 30, September 30, (in millions) 2015 2014 2015 2014 2015 2014 Fuel derivative contracts $ 330 * $ 104 * $ 166 * $ 3 * $ (15 ) $ (31 ) Interest rate derivatives 6 * 2 * 9 * 10 * (2 ) (3 ) Total $ 336 $ 106 $ 175 $ 13 $ (17 ) $ (34 ) *Net of tax (a) Amounts related to fuel derivative contracts and interest rate derivatives are included in Fuel and oil and Interest expense, respectively. (b) Amounts are included in Other (gains) losses, net. Derivatives not in cash flow hedging relationships (Gain) loss recognized in income on derivatives Three months ended Location of (gain) loss September 30, recognized in income (in millions) 2015 2014 on derivatives Fuel derivative contracts $ 239 $ 39 Other (gains) losses, net Derivatives not in cash flow hedging relationships (Gain) loss recognized in income on derivatives Nine months ended Location of (gain) loss September 30, recognized in income (in millions) 2015 2014 on derivatives Fuel derivative contracts $ 330 $ (1 ) Other (gains) losses, net The Company also recorded expense associated with premiums paid for fuel derivative contracts that settled/expired during the three months ended September 30, 2015 and 2014 of $33 million and $15 million , respectively, and the nine months ended September 30, 2015 and 2014 of $81 million and $49 million , respectively. These amounts are excluded from the Company’s measurement of effectiveness for related hedges and are included as a component of Other (gains) losses, net, in the unaudited Condensed Consolidated Statement of Comprehensive Income. The fair values of the derivative instruments, depending on the type of instrument, were determined by the use of present value methods or option value models with assumptions about commodity prices based on those observed in underlying markets or provided by third parties. Included in the Company’s cumulative net unrealized losses from fuel hedges as of September 30, 2015 , recorded in AOCI, were approximately $471 million in unrealized losses , net of taxes, which are expected to be realized in earnings during the twelve months subsequent to September 30, 2015 . Interest rate swaps The Company is party to certain interest rate swap agreements that are accounted for as either fair value hedges or cash flow hedges, as defined in the applicable accounting guidance for derivative instruments and hedging. Two of the Company's interest rate swap agreements qualify for the “shortcut” method of accounting for hedges, which dictates that the hedges are assumed to be perfectly effective, and, thus, there is no ineffectiveness to be recorded in earnings. For the Company’s interest rate swap agreements that do not qualify for the "shortcut" method of accounting, ineffectiveness is required to be measured at each reporting period. The ineffectiveness associated with all of the Company’s, including AirTran’s, interest rate hedges for all periods presented was not material. In February 2015, the Company terminated the fixed-to-floating interest rate swap agreements related to its $300 million 5.75% unsecured notes due 2016. The effect of this termination is such that the interest associated with the debt prospectively reverts back to its original fixed rate. As a result of the approximate $12 million gain realized on this transaction, which will be amortized over the remaining term of the corresponding unsecured notes, and based on projected interest rates at the date of termination, the Company does not believe its future interest expense associated with these unsecured notes will significantly differ from the expense it would have recorded had the unsecured notes remained at floating rates. Credit risk and collateral Credit exposure related to fuel derivative instruments is represented by the fair value of contracts that are an asset to the Company at the reporting date. At such times, these outstanding instruments expose the Company to credit loss in the event of nonperformance by the counterparties to the agreements. However, the Company has not experienced any significant credit loss as a result of counterparty nonperformance in the past. To manage credit risk, the Company selects and periodically reviews counterparties based on credit ratings, limits its exposure with respect to each counterparty, and monitors the market position of the fuel hedging program and its relative market position with each counterparty. At September 30, 2015 , the Company had agreements with all of its active counterparties containing early termination rights and/or bilateral collateral provisions whereby security is required if market risk exposure exceeds a specified threshold amount based on the counterparty credit rating. The Company also had agreements with counterparties in which cash deposits, letters of credit, and/or pledged aircraft are required to be posted as collateral whenever the net fair value of derivatives associated with those counterparties exceeds specific thresholds. The following table provides the fair values of fuel derivatives, amounts posted as collateral, and applicable collateral posting threshold amounts as of September 30, 2015 , at which such postings are triggered: Counterparty (CP) (in millions) A B C D E F Other (a) Total Fair value of fuel derivatives $ (514 ) $ (179 ) $ (153 ) $ (206 ) $ (108 ) $ (37 ) $ (33 ) $ (1,230 ) Cash collateral held (by) CP (238 ) (50 ) (39 ) (146 ) — (5 ) — (478 ) Aircraft collateral pledged to CP (210 ) (90 ) — — — — — (300 ) Letters of credit (LC) — — — — — — — — Option to substitute LC for aircraft (200) to (600)(h) (100) to (500)(d) N/A (150) to (550)(d) N/A N/A Option to substitute LC for cash N/A >(500)(e) (225) to (275)(e) (75) to (150) or >(550)(e) (g) (g) If credit rating is investment grade, fair value of fuel derivative level at which: Cash is provided to CP (50) to (200) or >(600) (50) to (100) or >(500) >(125) (75) to (150) or >(550) >(125) >(50) Cash is received from CP >50 >150 >175(c) >250 >75 >50 Aircraft or cash can be pledged to CP as collateral (200) to (600)(f) (100) to (500)(d) N/A (150) to (550)(d) N/A N/A If credit rating is non-investment grade, fair value of fuel derivative level at which: Cash is provided to CP (0) to (200) or >(600) (0) to (100) or >(500) (b) (0) to (150) or >(550) (b) (b) Cash is received from CP (b) (b) (b) (b) (b) (b) Aircraft or cash can be pledged to CP as collateral (200) to (600) (100) to (500) N/A (150) to (550) N/A N/A (a) Individual counterparties with fair value of fuel derivatives < $30 million . (b) Cash collateral is provided at 100 percent of fair value of fuel derivative contracts. (c) Thresholds may vary based on changes in credit ratings within investment grade. (d) The Company has the option of providing cash, letters of credit, or pledging aircraft as collateral. (e) The Company has the option of providing cash or letters of credit as collateral. (f) The Company has the option of providing cash or pledging aircraft as collateral. (g) The Company has the option to substitute letters of credit for 100 percent of cash collateral requirement. (h) The Company has the option of providing letters of credit in addition to aircraft collateral if the appraised value of the aircraft does not meet the collateral requirements.

COMPREHENSIVE INCOME

COMPREHENSIVE INCOME	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
COMPREHENSIVE INCOME	COMPREHENSIVE INCOME Comprehensive income includes changes in the fair value of certain financial derivative instruments that qualify for hedge accounting, unrealized gains and losses on certain investments, and actuarial gains/losses arising from the Company’s postretirement benefit obligation. The differences between Net income and Comprehensive income for the three and nine months ended September 30, 2015 and 2014 , were as follows: Three months ended September 30, (in millions) 2015 2014 NET INCOME $ 584 $ 329 Unrealized loss on fuel derivative instruments, net of deferred taxes of ($139) and ($124) (236 ) (210 ) Unrealized gain on interest rate derivative instruments, net of deferred taxes of $- and $3 — 6 Other, net of deferred taxes of ($2) and $1 (3 ) 1 Total other comprehensive loss $ (239 ) $ (203 ) COMPREHENSIVE INCOME $ 345 $ 126 Nine months ended September 30, (in millions) 2015 2014 NET INCOME $ 1,645 $ 946 Unrealized loss on fuel derivative instruments, net of deferred taxes of ($97) and ($60) (164 ) (101 ) Unrealized gain on interest rate derivative instruments, net of deferred taxes of $2 and $4 3 8 Other, net of deferred taxes of ($1) and $4 (4 ) 4 Total other comprehensive loss $ (165 ) $ (89 ) COMPREHENSIVE INCOME $ 1,480 $ 857 A rollforward of the amounts included in AOCI, net of taxes, is shown below for the three and nine months ended September 30, 2015 : (in millions) Fuel derivatives Interest rate derivatives Defined benefit plan items Other Deferred tax Accumulated other comprehensive income (loss) Balance at June 30, 2015 $ (1,063 ) $ (40 ) $ 41 $ 8 $ 390 $ (664 ) Changes in fair value (501 ) (5 ) — (5 ) 190 (321 ) Reclassification to earnings 126 5 — — (49 ) 82 Balance at September 30, 2015 $ (1,438 ) $ (40 ) $ 41 $ 3 $ 531 $ (903 ) (in millions) Fuel derivatives Interest rate derivatives Defined benefit plan items Other Deferred tax Accumulated other comprehensive income (loss) Balance at December 31, 2014 $ (1,177 ) $ (45 ) $ 41 $ 8 $ 435 $ (738 ) Changes in fair value (525 ) (10 ) — (5 ) 200 (340 ) Reclassification to earnings 264 15 — — (104 ) 175 Balance at September 30, 2015 $ (1,438 ) $ (40 ) $ 41 $ 3 $ 531 $ (903 ) The following tables illustrate the significant amounts reclassified out of each component of AOCI for the three and nine months ended September 30, 2015 : Three months ended September 30, 2015 (in millions) Amounts reclassified from AOCI Affected line item in the unaudited Condensed Consolidated Statement of Comprehensive Income AOCI components Unrealized loss on fuel derivative instruments $ 126 Fuel and oil expense 47 Less: Tax Expense $ 79 Net of tax Unrealized loss on interest rate derivative instruments $ 5 Interest expense 2 Less: Tax Expense $ 3 Net of tax Total reclassifications for the period $ 82 Net of tax Nine months ended September 30, 2015 (in millions) Amounts reclassified from AOCI Affected line item in the unaudited Condensed Consolidated Statement of Comprehensive Income AOCI components Unrealized loss on fuel derivative instruments $ 264 Fuel and oil expense 98 Less: Tax Expense $ 166 Net of tax Unrealized loss on interest rate derivative instruments $ 15 Interest expense 6 Less: Tax Expense $ 9 Net of tax Total reclassifications for the period $ 175 Net of tax

SUPPLEMENTAL FINANCIAL INFORMAT

SUPPLEMENTAL FINANCIAL INFORMATION	9 Months Ended
	Sep. 30, 2015
Disclosure Text Block [Abstract]
SUPPLEMENTAL FINANCIAL INFORMATION	SUPPLEMENTAL FINANCIAL INFORMATION Other assets (in millions) September 30, 2015 December 31, 2014 Derivative contracts $ 6 $ 13 Intangible assets (a) 469 363 Non-current investments 40 35 Other 172 123 Other assets $ 687 $ 534 (a) Intangible assets primarily consist of acquired leasehold rights to certain airport owned gates at Chicago’s Midway International Airport, takeoff and landing slots (a “slot” is the right of an air carrier, pursuant to regulations of the Federal Aviation Administration (“FAA”), to operate a takeoff or landing at a specific time at certain airports) at certain domestic slot-controlled airports, and certain intangible assets recognized from the AirTran acquisition. The increase in Intangible assets during 2015 was primarily due to the acquisition of two additional airport gate rights at Dallas Love Field, which were subleased from United Airlines. The purchase price paid for these airport gate rights was included as a component of Capital expenditures in the accompanying unaudited Condensed Consolidated Statement of Cash Flows. Accounts payable (in millions) September 30, 2015 December 31, 2014 Accounts payable trade $ 170 $ 123 Salaries payable 340 160 Excise and other tax withholdings payable 157 163 Aircraft maintenance payable 162 314 Fuel payable 46 85 Other payables 360 358 Accounts payable $ 1,235 $ 1,203 Accrued liabilities (in millions) September 30, 2015 December 31, 2014 ProfitSharing and savings plans $ 506 $ 374 Aircraft and other lease related obligations 86 159 Vacation pay 310 292 Health 77 84 Derivative contracts 541 174 Workers compensation 181 165 Property and income taxes 129 81 Other 219 236 Accrued liabilities $ 2,049 $ 1,565 Other noncurrent liabilities (in millions) September 30, 2015 December 31, 2014 Postretirement obligation $ 179 $ 169 Non-current lease-related obligations 164 193 Other deferred compensation 171 174 Deferred gains from sale and leaseback of aircraft 45 53 Derivative contracts 265 622 Other 107 44 Other noncurrent liabilities $ 931 $ 1,255 For further details on fuel derivative and interest rate derivative contracts, see Note 3 . Other Operating Expenses Other operating expenses consist of distribution costs, advertising expenses, personnel expenses, professional fees, and other operating costs, none of which individually exceed 10 percent of Operating expenses.

LEASES

LEASES	9 Months Ended
	Sep. 30, 2015
Leases [Abstract]
LEASES	LEASES On July 9, 2012, the Company signed an agreement with Delta Air Lines, Inc. and Boeing Capital Corp. to lease or sublease all 88 of AirTran's Boeing 717-200 aircraft (“B717s”) to Delta at agreed-upon lease rates. The first converted B717 was delivered to Delta in September 2013, and as of September 30, 2015 , the Company had delivered a total of 80 B717s to Delta. As the Company has previously disclosed, all B717s remaining at the Company were grounded on December 28, 2014. The Company currently expects the remaining eight B717s to be converted and delivered to Delta by early 2016. A total of 76 of the B717s are on operating lease, ten are owned, and two are on capital lease. The Company has paid and will continue to pay the majority of the costs to convert the aircraft to the Delta livery and perform certain maintenance checks prior to the delivery of each aircraft. The agreement to pay these conversion and maintenance costs for the leased aircraft is a “lease incentive” under applicable accounting guidance. The sublease terms for the 76 B717s on operating lease and the two B717s on capital lease coincide with the Company's remaining lease terms for these aircraft from the original lessor, which range from approximately three to nine years. The leasing of the ten B717s owned by the Company is subject to certain conditions, and the lease terms are for up to seven years, after which Delta has the option to purchase the aircraft at the then-prevailing market value. The Company accounts for the lease and sublease transactions with Delta as operating leases, sales type leases, and direct financing leases. The ten owned B717s will be accounted for as sales type leases, the two B717s classified by the Company as capital leases will be accounted for as direct financing leases, and the remaining 76 subleases will be accounted for as operating leases. With respect to the 80 B717s delivered to Delta as of September 30, 2015 , the Company had 73 operating leases, five sales type leases, and two direct financing leases. There are no contingent payments and no significant residual value conditions associated with the transaction. The accounting for this transaction is based on the guidance provided for lease transactions. For the components of this transaction finalized in third quarter 2012 and with respect to which the lease inception has been deemed to occur, the Company recorded a charge of approximately $137 million during third quarter 2012 . The charge represented the remaining estimated cost, at the scheduled date of delivery of each B717 to Delta (including the conversion, maintenance, and other contractual costs to be incurred), of the Company's lease of the 76 B717s that are accounted for as operating leases, net of the future sublease income from Delta and the remaining unfavorable aircraft lease liability established as of the acquisition date. The charges recorded by the Company for this transaction were included as a component of Acquisition and integration costs in the Company's unaudited Condensed Consolidated Statement of Comprehensive Income and were included as a component of Other, net in Cash flows from operating activities in the Company's unaudited Condensed Consolidated Statement of Cash Flows, and the corresponding liability for this transaction is included as a component of Current liabilities in the Company's unaudited Condensed Consolidated Balance Sheet. A rollforward of the Company's B717 lease/sublease liability for 2015 and 2014 is shown below: (in millions) B717 lease/sublease liability Balance at December 31, 2013 $ 122 Lease/sublease accretion 5 Lease/sublease expense adjustment 22 Lease/sublease payments, net (a) (86 ) Balance at December 31, 2014 $ 63 Lease/sublease accretion 1 Lease/sublease expense adjustment 5 Lease/sublease payments, net (a) (39 ) Balance at September 30, 2015 $ 30 (a) Includes lease conversion cost payments

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Fort Lauderdale-Hollywood International Airport In December 2013 , the Company entered into an agreement with Broward County, Florida, which owns and operates Fort Lauderdale-Hollywood International Airport, to oversee and manage the design and construction of the airport's Terminal 1 Modernization Project at a cost not to exceed $295 million . In addition to significant improvements to the existing Terminal 1, the project includes the design and construction of a new five-gate Concourse A with an international processing facility. Funding for the project will come directly from Broward County sources, but will flow through the Company in its capacity as manager of the project. Major construction on the project began during third quarter 2015 and is estimated to be completed during 2017 . The Company believes that due to its agreed upon role in overseeing and managing the project, it is considered the owner of the project for accounting purposes. As such, during construction the Company records expenditures as Assets constructed for others in the unaudited Condensed Consolidated Balance Sheet, along with a corresponding outflow within Assets constructed for others in the unaudited Condensed Consolidated Statement of Cash Flows, and an increase to Construction obligation (with a corresponding cash inflow from Financing activities in the unaudited Condensed Consolidated Statement of Cash Flows) as reimbursements are received from Broward County. As of September 30, 2015 , the Company had recorded construction costs related to the project of $17 million . Houston William P. Hobby Airport The Company entered into a Memorandum of Agreement (“MOA”) with the City of Houston (“City”), effective June 2012 , to expand the existing Houston Hobby airport facility. As provided in the MOA, the Company and the City have entered into an Airport Use and Lease Agreement (“Lease”) to control the execution of this expansion and the financial terms thereof. Per the MOA and Lease, this project provides for a new five-gate international terminal with international passenger processing facilities, expansion of the existing security checkpoint, and upgrades to the Southwest Airlines ticket counter area. The project was estimated to cost $156 million , and the Company agreed to provide the funding for, as well as management over, the project. In return, the capital cost portion of the rent the Company pays for the international facility will be waived from the initial occupancy until the expiration of the Lease. However, after completion of the project, the City has the option to buy out the Company's investment at the then-unamortized cost of the facility. This purchase would trigger payment of the previously waived capital cost component of rents owed the City. Additionally, some portion of the project is expected to qualify for rental credits that would be utilized upon completion of the facility against the Company’s lease payments at the airport. Construction began during third quarter 2013 and was effectively completed in October 2015, on time and under budget, at which time the Company began operating from the new facility. As a result of its significant involvement in the Houston Hobby project, the Company has evaluated its ongoing accounting requirements in consideration of accounting guidance provided for lessees involved in asset construction, and has determined that it is the owner of the facility for accounting purposes during the construction period. As such, during construction, the Company records expenditures as Assets constructed for others in the unaudited Condensed Consolidated Balance Sheet, along with a corresponding outflow within Assets constructed for others, in the unaudited Condensed Consolidated Statement of Cash Flows. As of September 30, 2015 , the Company had recorded construction costs related to Houston Hobby of $128 million . Los Angeles International Airport In March 2013, the Company executed a lease agreement with Los Angeles World Airports (“LAWA”), which owns and operates Los Angeles International Airport. Under the lease agreement, which was amended in June 2014, the Company is overseeing and managing the design, development, financing, construction and commissioning of the airport's Terminal 1 Modernization Project (the “Project”) at a cost not to exceed $526 million . The Project is being funded primarily using the Regional Airports Improvement Corporation ("RAIC"), which is a quasi-governmental special purpose entity that acts as a conduit borrower under a syndicated credit facility provided by a group of lenders. Loans made under the credit facility are being used to fund the development of the Project, and the outstanding loans will be repaid with the proceeds of LAWA’s payments to purchase completed Project phases. The Company has guaranteed the obligations of the RAIC under the credit facility. Construction on the Project began during 2014 and is estimated to be completed during 2018. The Company believes that due to its agreed upon role in overseeing and managing the Project, it is considered the owner of the Project for accounting purposes. LAWA will reimburse the Company for the non-proprietary renovations, while the Company will not be reimbursed for proprietary renovations. As a result, all of the costs incurred to fund the Project are included within Assets constructed for others and all amounts that have been or will be reimbursed will be included within Construction obligation on the accompanying unaudited Condensed Consolidated Balance Sheet. As of September 30, 2015 , the Company had recorded construction costs related to the Project of $151 million , which were classified and included in Assets constructed for others and as Construction obligation in the accompanying unaudited Condensed Consolidated Balance Sheet. Dallas Love Field During 2008, the City of Dallas approved the Love Field Modernization Program (“LFMP”), a project to reconstruct Dallas Love Field with modern, convenient air travel facilities. Pursuant to a Program Development Agreement with the City of Dallas and the Love Field Airport Modernization Corporation (or “LFAMC,” a Texas non-profit “local government corporation” established by the City of Dallas to act on the City of Dallas' behalf to facilitate the development of the LFMP), the Company managed this project. Major construction commenced during 2010, and the project was effectively completed by December 31, 2014. The project consists of the complete replacement of gate facilities with a new 20-gate facility, including infrastructure, systems and equipment, aircraft parking apron, fueling system, roadways and terminal curbside, baggage handling systems, passenger loading bridges and support systems, and other supporting infrastructure. New ticketing and check-in areas opened during fourth quarter 2012, 12 new gates and new concessions opened in 2013, and the remaining gates opened during October 2014. Although the City of Dallas has received commitments from various sources that are helping to fund portions of the LFMP project, including the FAA, the Transportation Security Administration, and the City of Dallas' Aviation Fund, the majority of the funds used are from the issuance of bonds. During fourth quarter 2010, $310 million of such bonds were issued by the LFAMC, and the Company has guaranteed principal and interest payments on the bonds. An additional tranche of such bonds totaling $146 million was issued during second quarter 2012, and the Company has guaranteed the principal and interest payments on these bonds as well. The Company currently expects that as a result of the funding commitments from the above mentioned sources and the bonds that have been issued thus far, no further bond issuances and related guarantees from the Company will be required to complete the LFMP project. In conjunction with the Company's significant presence at Dallas Love Field and other factors, the Company agreed to manage the LFMP project. Based on these facts, the Company has evaluated its ongoing accounting requirements in consideration of accounting guidance provided for lessees involved in asset construction. The Company has recorded and will continue to record an asset and corresponding obligation for the cost of the LFMP project as the construction of the facility occurs. As of September 30, 2015 , the Company had recorded LFMP gross construction costs, including capitalized interest, of $527 million within Assets constructed for others and had recorded a net liability of $516 million within Construction obligation in its unaudited Condensed Consolidated Balance Sheet. Upon completion of different phases of the LFMP project, the Company has placed the associated assets in service and has begun depreciating the assets over their estimated useful lives. In addition, upon the effective completion of construction, the Company noted the project assets did not meet the qualifications for sale and leaseback accounting due to the Company's continuing involvement with the facility, as defined; therefore, for financial reporting purposes, these assets will remain on the Company's books until the bonds issued by the City of Dallas are repaid. The corresponding LFMP liabilities will be reduced primarily through the Company's airport rental payments to the City of Dallas as the construction costs of the project are passed through to the Company via recurring airport rates and charges. These payments are reflected as Repayment of construction obligation in the unaudited Condensed Consolidated Statement of Cash Flows. Contingencies The Company is from time to time subject to various legal proceedings and claims arising in the ordinary course of business, including, but not limited to, examinations by the IRS. The Company's management does not expect that the outcome in any of its currently ongoing legal proceedings or the outcome of any adjustments presented by the IRS, individually or collectively, will have a material adverse effect on the Company's financial condition, results of operations, or cash flow.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Accounting standards pertaining to fair value measurements establish a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. As of September 30, 2015 , the Company held certain items that are required to be measured at fair value on a recurring basis. These included cash equivalents, short-term investments (primarily treasury bills and certificates of deposit), certain noncurrent investments, interest rate derivative contracts, fuel derivative contracts, and available-for-sale securities. The majority of the Company’s short-term investments consist of instruments classified as Level 1. However, the Company has certificates of deposit, commercial paper, and Eurodollar time deposits that are classified as Level 2, due to the fact that the fair value for these instruments is determined utilizing observable inputs in non-active markets. Noncurrent investments consist of certain auction rate securities, primarily those collateralized by student loan portfolios, which are guaranteed by the U.S. Government. Other available-for-sale securities primarily consist of investments associated with the Company’s excess benefit plan. The Company’s fuel and interest rate derivative instruments consist of over-the-counter contracts, which are not traded on a public exchange. Fuel derivative instruments include swaps, as well as different types of option contracts, whereas interest rate derivatives consist solely of swap agreements. See Note 3 for further information on the Company’s derivative instruments and hedging activities. The fair values of swap contracts are determined based on inputs that are readily available in public markets or can be derived from information available in publicly quoted markets. Therefore, the Company has categorized these swap contracts as Level 2. The Company’s Treasury Department, which reports to the Chief Financial Officer, determines the value of option contracts utilizing an option pricing model based on inputs that are either readily available in public markets, can be derived from information available in publicly quoted markets, or are provided by financial institutions that trade these contracts. The option pricing model used by the Company is an industry standard model for valuing options and is the same model used by the broker/dealer community (i.e., the Company’s counterparties). The inputs to this option pricing model are the option strike price, underlying price, risk free rate of interest, time to expiration, and volatility. Because certain inputs used to determine the fair value of option contracts are unobservable (principally implied volatility), the Company has categorized these option contracts as Level 3. Volatility information is obtained from external sources, but is analyzed by the Company for reasonableness and compared to similar information received from other external sources. The fair value of option contracts considers both the intrinsic value and any remaining time value associated with those derivatives that have not yet settled. The Company also considers counterparty credit risk and its own credit risk in its determination of all estimated fair values. To validate the reasonableness of the Company’s option pricing model, on a monthly basis, the Company compares its option valuations to third party valuations. If any significant differences were to be noted, they would be researched in order to determine the reason. However, historically, no significant differences have been noted. The Company has consistently applied these valuation techniques in all periods presented and believes it has obtained the most accurate information available for the types of derivative contracts it holds. Included in Other available-for-sale securities are the Company’s investments associated with its excess benefit plan which consist of investment funds for which market prices are readily available. This plan is a non-qualified deferred compensation plan designed to hold Employee contributions in excess of limits established by Section 415 of the Internal Revenue Code of 1986, as amended. Payments under this plan are made based on the participant’s distribution election and plan balance. Assets related to the funded portion of the deferred compensation plan are held in a rabbi trust, and the Company remains liable to these participants for the unfunded portion of the plan. The Company records changes in the fair value of the asset in the Company’s earnings. All of the Company’s auction rate security instruments, totaling $ 27 million (net) at September 30, 2015 , are classified as available-for-sale securities and are reflected at their estimated fair value in the unaudited Condensed Consolidated Balance Sheet. The Company’s Treasury Department determines the estimated fair values of these securities utilizing a discounted cash flow analysis. The Company has performed, and routinely updates, a valuation for each of its auction rate security instruments, considering, among other items, the collateralization underlying the security investments, the expected future cash flows, including the final maturity, associated with the securities, estimates of the next time the security is expected to have a successful auction or return to full par value, forecasted reset rates based on the LIBOR or the issuer’s net loan rate, and a counterparty credit spread. To validate the reasonableness of the Company’s discounted cash flow analyses, the Company compares its valuations to third party valuations on a quarterly basis. The following tables present the Company’s assets and liabilities that are measured at fair value on a recurring basis at September 30, 2015 , and December 31, 2014 : Fair value measurements at reporting date using: Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs Description September 30, 2015 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents Cash equivalents (a) $ 1,528 $ 1,528 $ — $ — Commercial paper 125 — 125 — Certificates of deposit 25 — 25 — Eurodollar time deposits 62 — 62 — Short-term investments: Treasury bills 1,149 1,149 — — Certificates of deposit 207 — 207 — Noncurrent investments (b) Auction rate securities 27 — — 27 Interest rate derivatives 6 — 6 — Fuel derivatives: Swap contracts (c) 818 — 818 — Option contracts (c) 912 — — 912 Other available-for-sale securities 62 62 — — Total assets $ 4,921 $ 2,739 $ 1,243 $ 939 Liabilities Fuel derivatives: Swap contracts (c) $ (679 ) $ — $ (679 ) $ — Option contracts (c) (2,281 ) — — (2,281 ) Interest rate derivatives (54 ) — (54 ) — Total liabilities $ (3,014 ) $ — $ (733 ) $ (2,281 ) (a) Cash equivalents are primarily composed of money market investments. (b) Noncurrent investments are included in Other assets in the unaudited Condensed Consolidated Balance Sheet. (c) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net liability. Fair value measurements at reporting date using: Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs Description December 31, 2014 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents Cash equivalents (a) $ 1,110 $ 1,110 $ — $ — Commercial paper 70 — 70 — Certificates of deposit 4 — 4 — Eurodollar time deposits 98 — 98 — Short-term investments: Treasury bills 1,450 1,450 — — Certificates of deposit 256 — 256 — Noncurrent investments (b) Auction rate securities 27 — — 27 Interest rate derivatives 13 — 13 — Fuel derivatives: Swap contracts (c) 455 — 455 — Option contracts (c) 892 — — 892 Other available-for-sale securities 68 63 — 5 Total assets $ 4,443 $ 2,623 $ 896 $ 924 Liabilities Fuel derivatives: Swap contracts (c) $ (365 ) $ — $ (365 ) $ — Option contracts (c) (1,983 ) — — (1,983 ) Interest rate derivatives (61 ) — (61 ) — Total liabilities $ (2,409 ) $ — $ (426 ) $ (1,983 ) (a) Cash equivalents are primarily composed of money market investments. (b) Noncurrent investments are included in Other assets in the unaudited Condensed Consolidated Balance Sheet. (c) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net liability. The Company had no transfers of assets or liabilities between any of the above levels during the nine months ended September 30, 2015 , or the year ended December 31, 2014 . The following tables present the Company’s activity for items measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the three and nine months ended September 30, 2015 : Fair value measurements using significant unobservable inputs (Level 3) Fuel Auction rate Other (in millions) derivatives securities securities Total Balance at June 30, 2015 $ (1,055 ) $ 27 $ — $ (1,028 ) Total losses (realized or unrealized) Included in earnings (405 ) — — (405 ) Included in other comprehensive income (488 ) — — (488 ) Purchases 408 (a) — — 408 Sales (11 ) (a) — — (11 ) Settlements 182 — — 182 Balance at September 30, 2015 $ (1,369 ) $ 27 (b) $ — $ (1,342 ) The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015 $ (317 ) $ — $ — $ (317 ) (a) The purchase and sale of fuel derivatives are recorded gross based on the structure of the derivative instrument and whether a contract with multiple derivatives is purchased as a single instrument or separate instruments. (b) Included in Other assets in the unaudited Condensed Consolidated Balance Sheet. Fair value measurements using significant unobservable inputs (Level 3) Fuel Auction rate Other (in millions) derivatives securities securities Total Balance at December 31, 2014 $ (1,091 ) $ 27 $ 5 $ (1,059 ) Total losses (realized or unrealized) Included in earnings (413 ) — (1 ) (414 ) Included in other comprehensive income (517 ) — — (517 ) Purchases 652 (a) — — 652 Sales (182 ) (a) — (4 ) (186 ) Settlements 182 — — 182 Balance at September 30, 2015 $ (1,369 ) $ 27 (b) $ — $ (1,342 ) The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015 $ (324 ) $ — $ — $ (324 ) (a) The purchase and sale of fuel derivatives are recorded gross based on the structure of the derivative instrument and whether a contract with multiple derivatives is purchased as a single instrument or separate instruments. (b) Included in Other assets in the unaudited Condensed Consolidated Balance Sheet. The significant unobservable input used in the fair value measurement of the Company’s derivative option contracts is implied volatility. Holding other inputs constant, a significant increase (decrease) in implied volatility would result in a significantly higher (lower) fair value measurement, respectively, for the Company’s derivative option contracts. The significant unobservable inputs used in the fair value measurement of the Company’s auction rate securities are time to principal recovery, an illiquidity premium, and counterparty credit spread. Holding other inputs constant, a significant increase (decrease) in such unobservable inputs would result in a significantly lower (higher) fair value measurement, respectively. The following table presents a range of the unobservable inputs utilized in the fair value measurements of the Company’s assets and liabilities classified as Level 3 at September 30, 2015 : Quantitative information about Level 3 fair value measurements Valuation technique Unobservable input Period (by year) Range Fuel derivatives Option model Implied volatility Fourth quarter 2015 21-41% 2016 24-41% 2017 22-34% 2018 16-29% Auction rate securities Discounted cash flow Time to principal recovery 8 years Illiquidity premium 3-4% Counterparty credit spread 1-2% The carrying amounts and estimated fair values of the Company’s long-term debt (including current maturities), as well as the applicable fair value hierarchy tier, at September 30, 2015 , are presented in the table below. The fair values of the Company’s publicly held long-term debt are determined based on inputs that are readily available in public markets or can be derived from information available in publicly quoted markets; therefore, the Company has categorized these agreements as Level 2. Six of the Company’s debt agreements are not publicly held. The Company has determined the estimated fair value of this debt to be Level 3, as certain inputs used to determine the fair value of these agreements are unobservable. The Company utilizes indicative pricing from counterparties and a discounted cash flow method to estimate the fair value of the Level 3 items. (in millions) Carrying value Estimated fair value Fair value level hierarchy 5.75% Notes due 2016 $ 308 $ 324 Level 2 5.25% Convertible Senior Notes due 2016 112 294 Level 2 5.125% Notes due 2017 310 326 Level 2 French Credit Agreements due 2018 - 1.15% 31 31 Level 3 Fixed-rate 737 Aircraft Notes payable through 2018 - 7.02% 18 19 Level 3 2.75% Notes due 2019 308 313 Level 2 Term Loan Agreement due 2019 - 6.315% 152 158 Level 3 Term Loan Agreement due 2019 - 4.84% 36 38 Level 3 Term Loan Agreement due 2020 - 5.223% 340 337 Level 3 Floating-rate 737 Aircraft Notes payable through 2020 267 261 Level 3 Pass Through Certificates due 2022 - 6.24% 339 380 Level 2 7.375% Debentures due 2027 132 160 Level 2

NET INCOME PER SHARE

NET INCOME PER SHARE	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
NET INCOME PER SHARE	NET INCOME PER SHARE The following table sets forth the computation of basic and diluted net income per share (in millions, except per share amounts): Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 NUMERATOR: Net income $ 584 $ 329 $ 1,645 $ 946 Incremental income effect of interest on 5.25% convertible notes 1 1 3 3 Net income after assumed conversion $ 585 $ 330 $ 1,648 $ 949 DENOMINATOR: Weighted-average shares outstanding, basic 655 683 665 690 Dilutive effect of Employee stock options and restricted stock units 2 2 2 3 Dilutive effect of 5.25% convertible notes 6 6 6 6 Adjusted weighted-average shares outstanding, diluted 663 691 673 699 NET INCOME PER SHARE: Basic $ 0.89 $ 0.48 $ 2.47 $ 1.37 Diluted $ 0.88 $ 0.48 $ 2.45 $ 1.36

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Basis of Presentation	The unaudited Condensed Consolidated Financial Statements for the interim periods ended September 30, 2015 and 2014 include all adjustments which are, in the opinion of management, necessary for a fair presentation of the results for the interim periods. This includes all normal and recurring adjustments and elimination of significant intercompany transactions. Financial results for the Company and airlines in general can be seasonal in nature. In many years, the Company's revenues, as well as its operating income and net income, have been better in its second and third fiscal quarters than in its first and fourth fiscal quarters. Air travel is also significantly impacted by general economic conditions, the amount of disposable income available to consumers, unemployment levels, corporate travel budgets, and other factors beyond the Company's control. These and other factors, such as the price of jet fuel in some periods, the nature of the Company's fuel hedging program, the periodic volatility of commodities used by the Company for hedging jet fuel, and the requirements related to hedge accounting, have created, and may continue to create, significant volatility in the Company's financial results. See Note 3 for further information on fuel and the Company's hedging program. Operating results for the three and nine months ended September 30, 2015 , are not necessarily indicative of the results that may be expected for future quarters or for the year ended December 31, 2015 . For further information, refer to the Consolidated Financial Statements and footnotes thereto included in the Southwest Airlines Co. Annual Report on Form 10-K for the year ended December 31, 2014 .
Derivatives	The Company is party to certain interest rate swap agreements that are accounted for as either fair value hedges or cash flow hedges, as defined in the applicable accounting guidance for derivative instruments and hedging. Two of the Company's interest rate swap agreements qualify for the “shortcut” method of accounting for hedges, which dictates that the hedges are assumed to be perfectly effective, and, thus, there is no ineffectiveness to be recorded in earnings. For the Company’s interest rate swap agreements that do not qualify for the "shortcut" method of accounting, ineffectiveness is required to be measured at each reporting period. Upon proper qualification, the Company accounts for its fuel derivative instruments as cash flow hedges. Generally, utilizing hedge accounting, all periodic changes in fair value of the derivatives designated as hedges that are considered to be effective are recorded in Accumulated other comprehensive income (loss) ("AOCI") until the underlying jet fuel is consumed. See Note 4 . The Company’s results are subject to the possibility that periodic changes will not be effective, as defined, or that the derivatives will no longer qualify for hedge accounting. Ineffectiveness results when the change in the fair value of the derivative instrument exceeds the change in the value of the Company’s expected future cash outlay to purchase and consume jet fuel. To the extent that the periodic changes in the fair value of the derivatives are ineffective, the ineffective portion is recorded to Other (gains) losses, net, in the unaudited Condensed Consolidated Statement of Comprehensive Income. Likewise, if a hedge ceases to qualify for hedge accounting, any change in the fair value of derivative instruments since the last reporting period is recorded to Other (gains) losses, net, in the unaudited Condensed Consolidated Statement of Comprehensive Income in the period of the change; however, any amounts previously recorded to AOCI would remain there until such time as the original forecasted transaction occurs, at which time these amounts would be reclassified to Fuel and oil expense. When the Company has sold derivative positions in order to effectively “close” or offset a derivative already held as part of its fuel derivative instrument portfolio, any subsequent changes in fair value of those positions are marked to market through earnings. Likewise, any changes in fair value of those positions that were offset by entering into the sold positions and were de-designated as hedges are concurrently marked to market through earnings. However, any changes in value related to hedges that were deferred as part of AOCI while designated as a hedge would remain until the originally forecasted transaction occurs. In a situation where it becomes probable that a fuel hedged forecasted transaction will not occur, any gains and/or losses that have been recorded to AOCI would be required to be immediately reclassified into earnings. The Company did not have any such situations occur during 2014 , or during the nine months ended September 30, 2015 . In some situations, an entire commodity type used in hedging may cease to qualify for special hedge accounting treatment.
Fair Value of Financial Instruments	Accounting standards pertaining to fair value measurements establish a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. As of September 30, 2015 , the Company held certain items that are required to be measured at fair value on a recurring basis. These included cash equivalents, short-term investments (primarily treasury bills and certificates of deposit), certain noncurrent investments, interest rate derivative contracts, fuel derivative contracts, and available-for-sale securities. The majority of the Company’s short-term investments consist of instruments classified as Level 1. However, the Company has certificates of deposit, commercial paper, and Eurodollar time deposits that are classified as Level 2, due to the fact that the fair value for these instruments is determined utilizing observable inputs in non-active markets. Noncurrent investments consist of certain auction rate securities, primarily those collateralized by student loan portfolios, which are guaranteed by the U.S. Government. Other available-for-sale securities primarily consist of investments associated with the Company’s excess benefit plan. The Company’s fuel and interest rate derivative instruments consist of over-the-counter contracts, which are not traded on a public exchange. Fuel derivative instruments include swaps, as well as different types of option contracts, whereas interest rate derivatives consist solely of swap agreements. See Note 3 for further information on the Company’s derivative instruments and hedging activities. The fair values of swap contracts are determined based on inputs that are readily available in public markets or can be derived from information available in publicly quoted markets. Therefore, the Company has categorized these swap contracts as Level 2. The Company’s Treasury Department, which reports to the Chief Financial Officer, determines the value of option contracts utilizing an option pricing model based on inputs that are either readily available in public markets, can be derived from information available in publicly quoted markets, or are provided by financial institutions that trade these contracts. The option pricing model used by the Company is an industry standard model for valuing options and is the same model used by the broker/dealer community (i.e., the Company’s counterparties). The inputs to this option pricing model are the option strike price, underlying price, risk free rate of interest, time to expiration, and volatility. Because certain inputs used to determine the fair value of option contracts are unobservable (principally implied volatility), the Company has categorized these option contracts as Level 3. Volatility information is obtained from external sources, but is analyzed by the Company for reasonableness and compared to similar information received from other external sources. The fair value of option contracts considers both the intrinsic value and any remaining time value associated with those derivatives that have not yet settled. The Company also considers counterparty credit risk and its own credit risk in its determination of all estimated fair values. To validate the reasonableness of the Company’s option pricing model, on a monthly basis, the Company compares its option valuations to third party valuations. If any significant differences were to be noted, they would be researched in order to determine the reason. However, historically, no significant differences have been noted. The Company has consistently applied these valuation techniques in all periods presented and believes it has obtained the most accurate information available for the types of derivative contracts it holds.
Revenue Recognition, Multiple-deliverable Arrangements, Description	During July 2015, the Company executed an amended co-branded credit card agreement (“Agreement”) with Chase Bank USA, N.A. (“Chase”), through which the Company sells loyalty points and other items to Chase. The Company's Rapid Rewards program members ("Members") are able to accrue loyalty points based on purchases using the Chase co-branded Southwest Visa credit card. The Agreement materially modifies the previously existing agreement between Chase and the Company. Consideration received as part of this Agreement is subject to ASU 2009-13, "Multiple-Deliverable Revenue Arrangements - a consensus of the FASB Emerging Issues Task Force".

Accounting Changes and New Acco

Accounting Changes and New Accounting Pronouncements (Tables)	9 Months Ended
	Sep. 30, 2015
Accounting Changes and Error Corrections [Abstract]
Schedule of New Changes in Accounting Principles - Chase Agreement	The impacts on revenue and earnings from this change in accounting principle are as follows: (in millions, except per share amounts) Three months ended September 30, 2015 Nine months ended September 30, 2015 Passenger revenue $ (40 ) $ (40 ) Special revenue adjustment 172 172 Other revenue 171 171 Operating revenues $ 303 $ 303 Net income $ 161 $ 161 Net income per basic share $ 0.25 $ 0.24 Net income per diluted share $ 0.24 $ 0.24
Schedule of Change in Accounting Estimate - Spoilage	The impacts on revenue and earnings for the lower rate applied in fourth quarter 2014 are as follows: (in millions, except per share amounts) Three months ended September 30, 2015 Nine months ended September 30, 2015 Passenger revenue $ 30 $ 115 Net income $ 16 $ 61 Net income per basic share $ 0.02 $ 0.09 Net income per diluted share $ 0.02 $ 0.09

Financial Derivative Instrume16

Financial Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Volume of Fuel Hedging	The following table provides information about the Company’s volume of fuel hedging for the years 2015 through 2018 on an “economic” basis: Fuel hedged as of September 30, 2015 Derivative underlying commodity type as of Period (by year) (gallons in millions) September 30, 2015 Fourth quarter 2015 — (a) 2016 1,188 (b) Brent crude oil, Heating oil, and Gulf Coast jet fuel 2017 1,294 (b) WTI crude and Brent crude oil 2018 466 (b) Brent crude oil (a) The Company is effectively unhedged for fourth quarter 2015 at current price levels. While the Company still holds derivative contracts as of September 30, 2015 , that will settle during fourth quarter 2015, the losses associated with those contracts are substantially locked in. However, if market prices were to increase or decrease significantly related to the fourth quarter 2015 positions prior to these contracts settling, the losses incurred at settlement could be slightly lower or higher than currently expected amounts during that period. (b) Due to the types of derivatives and commodities utilized by the Company and different price levels of those contracts, this volume represents the maximum "economic" net hedge in place. The Company's average "economic" net hedge of estimated fuel consumption covered by fuel derivative contracts is lower than this maximum volume, may vary significantly as market prices fluctuate, and begins to provide hedge coverage at price levels above current market prices.
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the location of all assets and liabilities associated with the Company’s derivative instruments within the unaudited Condensed Consolidated Balance Sheet: Asset derivatives Liability derivatives Balance Sheet Fair value at Fair value at Fair value at Fair value at (in millions) location 9/30/2015 12/31/2014 9/30/2015 12/31/2014 Derivatives designated as hedges* Fuel derivative contracts (gross) Accrued liabilities $ 36 $ — $ 414 $ — Fuel derivative contracts (gross) Other noncurrent liabilities 54 — 596 643 Interest rate derivative contracts Other assets 6 13 — — Interest rate derivative contracts Other noncurrent liabilities — — 54 61 Total derivatives designated as hedges $ 96 $ 13 $ 1,064 $ 704 Derivatives not designated as hedges* Fuel derivative contracts (gross) Accrued liabilities $ 1,358 $ 1,190 $ 1,536 $ 1,432 Fuel derivative contracts (gross) Other noncurrent liabilities 282 157 414 273 Total derivatives not designated as hedges $ 1,640 $ 1,347 $ 1,950 $ 1,705 Total derivatives $ 1,736 $ 1,360 $ 3,014 $ 2,409 * Represents the position of each trade before consideration of offsetting positions with each counterparty and does not include the impact of cash collateral deposits provided to or received from counterparties. See discussion of credit risk and collateral following in this Note.
Cash Collateral Deposits Due To Or From Third Parties and Net Unrealized Losses	In addition, the Company had the following amounts associated with fuel derivative instruments and hedging activities in its unaudited Condensed Consolidated Balance Sheet: Balance Sheet September 30, December 31, (in millions) location 2015 2014 Cash collateral deposits provided to counterparties for fuel contracts - current Offset against Accrued liabilities $ 15 $ 68 Cash collateral deposits provided to counterparties for fuel Offset against Other noncurrent liabilities 463 198 Due to third parties for fuel contracts Accounts payable 41 16
Offsetting Assets	(a) The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5 . The Company has the following recognized financial assets and financial liabilities resulting from those transactions that meet the scope of the disclosure requirements as necessitated by applicable accounting guidance for balance sheet offsetting: Offsetting of derivative assets (in millions) (i) (ii) (iii) = (i) + (ii) (i) (ii) (iii) = (i) + (ii) September 30, 2015 December 31, 2014 Description Balance Sheet location Gross amounts of recognized assets Gross amounts offset in the Balance Sheet Net amounts of assets presented in the Balance Sheet (a) Gross amounts of recognized assets Gross amounts offset in the Balance Sheet Net amounts of assets presented in the Balance Sheet (a) Fuel derivative contracts Accrued liabilities $ 1,409 $ (1,409 ) $ — $ 1,258 $ (1,258 ) $ — Fuel derivative contracts Other noncurrent liabilities $ 799 $ (799 ) $ — $ 355 $ (355 ) $ — Interest rate derivative contracts Other assets $ 6 $ — $ 6 $ 13 $ — $ 13
Offsetting Liabilities	Offsetting of derivative liabilities (in millions) (i) (ii) (iii) = (i) + (ii) (i) (ii) (iii) = (i) + (ii) September 30, 2015 December 31, 2014 Description Balance Sheet location Gross amounts of recognized liabilities Gross amounts offset in the Balance Sheet Net amounts of liabilities presented in the Balance Sheet (a) Gross amounts of recognized liabilities Gross amounts offset in the Balance Sheet Net amounts of liabilities presented in the Balance Sheet (a) Fuel derivative contracts Accrued liabilities $ 1,950 $ (1,409 ) $ 541 $ 1,432 $ (1,258 ) $ 174 Fuel derivative contracts Other noncurrent liabilities $ 1,010 $ (799 ) $ 211 $ 916 $ (355 ) $ 561 Interest rate derivative contracts Other noncurrent liabilities $ 54 $ — $ 54 $ 61 $ — $ 61 (a) The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5 .
Derivatives in Cash Flow Hedging Relationships	The following tables present the impact of derivative instruments and their location within the unaudited Condensed Consolidated Statement of Comprehensive Income for the three and nine months ended September 30, 2015 and 2014 : Derivatives in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives (effective portion) (Gain) loss reclassified from AOCI into income (effective portion) (a) (Gain) loss recognized in income on derivatives (ineffective portion) (b) Three months ended Three months ended Three months ended September 30, September 30, September 30, (in millions) 2015 2014 2015 2014 2015 2014 Fuel derivative contracts $ 315 * $ 214 * $ 79 * $ 4 * $ — $ 11 Interest rate derivatives 3 * (2 ) * 3 * 4 * — (2 ) Total $ 318 $ 212 $ 82 $ 8 $ — $ 9 *Net of tax (a) Amounts related to fuel derivative contracts and interest rate derivatives are included in Fuel and oil and Interest expense, respectively. (b) Amounts are included in Other (gains) losses, net. Derivatives in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives (effective portion) (Gain) loss reclassified from AOCI into income (effective portion)(a) (Gain) loss recognized in income on derivatives (ineffective portion)(b) Nine months ended Nine months ended Nine months ended September 30, September 30, September 30, (in millions) 2015 2014 2015 2014 2015 2014 Fuel derivative contracts $ 330 * $ 104 * $ 166 * $ 3 * $ (15 ) $ (31 ) Interest rate derivatives 6 * 2 * 9 * 10 * (2 ) (3 ) Total $ 336 $ 106 $ 175 $ 13 $ (17 ) $ (34 ) *Net of tax (a) Amounts related to fuel derivative contracts and interest rate derivatives are included in Fuel and oil and Interest expense, respectively. (b) Amounts are included in Other (gains) losses, net.
Derivatives Not in Cash Flow Hedging Relationships	Derivatives not in cash flow hedging relationships (Gain) loss recognized in income on derivatives Three months ended Location of (gain) loss September 30, recognized in income (in millions) 2015 2014 on derivatives Fuel derivative contracts $ 239 $ 39 Other (gains) losses, net Derivatives not in cash flow hedging relationships (Gain) loss recognized in income on derivatives Nine months ended Location of (gain) loss September 30, recognized in income (in millions) 2015 2014 on derivatives Fuel derivative contracts $ 330 $ (1 ) Other (gains) losses, net
Fair Values of Fuel Derivatives, Amounts Posted as Collateral, and Collateral Posting Threshold Amounts	The following table provides the fair values of fuel derivatives, amounts posted as collateral, and applicable collateral posting threshold amounts as of September 30, 2015 , at which such postings are triggered: Counterparty (CP) (in millions) A B C D E F Other (a) Total Fair value of fuel derivatives $ (514 ) $ (179 ) $ (153 ) $ (206 ) $ (108 ) $ (37 ) $ (33 ) $ (1,230 ) Cash collateral held (by) CP (238 ) (50 ) (39 ) (146 ) — (5 ) — (478 ) Aircraft collateral pledged to CP (210 ) (90 ) — — — — — (300 ) Letters of credit (LC) — — — — — — — — Option to substitute LC for aircraft (200) to (600)(h) (100) to (500)(d) N/A (150) to (550)(d) N/A N/A Option to substitute LC for cash N/A >(500)(e) (225) to (275)(e) (75) to (150) or >(550)(e) (g) (g) If credit rating is investment grade, fair value of fuel derivative level at which: Cash is provided to CP (50) to (200) or >(600) (50) to (100) or >(500) >(125) (75) to (150) or >(550) >(125) >(50) Cash is received from CP >50 >150 >175(c) >250 >75 >50 Aircraft or cash can be pledged to CP as collateral (200) to (600)(f) (100) to (500)(d) N/A (150) to (550)(d) N/A N/A If credit rating is non-investment grade, fair value of fuel derivative level at which: Cash is provided to CP (0) to (200) or >(600) (0) to (100) or >(500) (b) (0) to (150) or >(550) (b) (b) Cash is received from CP (b) (b) (b) (b) (b) (b) Aircraft or cash can be pledged to CP as collateral (200) to (600) (100) to (500) N/A (150) to (550) N/A N/A (a) Individual counterparties with fair value of fuel derivatives < $30 million . (b) Cash collateral is provided at 100 percent of fair value of fuel derivative contracts. (c) Thresholds may vary based on changes in credit ratings within investment grade. (d) The Company has the option of providing cash, letters of credit, or pledging aircraft as collateral. (e) The Company has the option of providing cash or letters of credit as collateral. (f) The Company has the option of providing cash or pledging aircraft as collateral. (g) The Company has the option to substitute letters of credit for 100 percent of cash collateral requirement. (h) The Company has the option of providing letters of credit in addition to aircraft collateral if the appraised value of the aircraft does not meet the collateral requirements.

Comprehensive Income (Tables)

Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
Components of Comprehensive Income	The differences between Net income and Comprehensive income for the three and nine months ended September 30, 2015 and 2014 , were as follows: Three months ended September 30, (in millions) 2015 2014 NET INCOME $ 584 $ 329 Unrealized loss on fuel derivative instruments, net of deferred taxes of ($139) and ($124) (236 ) (210 ) Unrealized gain on interest rate derivative instruments, net of deferred taxes of $- and $3 — 6 Other, net of deferred taxes of ($2) and $1 (3 ) 1 Total other comprehensive loss $ (239 ) $ (203 ) COMPREHENSIVE INCOME $ 345 $ 126 Nine months ended September 30, (in millions) 2015 2014 NET INCOME $ 1,645 $ 946 Unrealized loss on fuel derivative instruments, net of deferred taxes of ($97) and ($60) (164 ) (101 ) Unrealized gain on interest rate derivative instruments, net of deferred taxes of $2 and $4 3 8 Other, net of deferred taxes of ($1) and $4 (4 ) 4 Total other comprehensive loss $ (165 ) $ (89 ) COMPREHENSIVE INCOME $ 1,480 $ 857
Rollforward of the Amounts Included in AOCI, Net of Taxes	A rollforward of the amounts included in AOCI, net of taxes, is shown below for the three and nine months ended September 30, 2015 : (in millions) Fuel derivatives Interest rate derivatives Defined benefit plan items Other Deferred tax Accumulated other comprehensive income (loss) Balance at June 30, 2015 $ (1,063 ) $ (40 ) $ 41 $ 8 $ 390 $ (664 ) Changes in fair value (501 ) (5 ) — (5 ) 190 (321 ) Reclassification to earnings 126 5 — — (49 ) 82 Balance at September 30, 2015 $ (1,438 ) $ (40 ) $ 41 $ 3 $ 531 $ (903 ) (in millions) Fuel derivatives Interest rate derivatives Defined benefit plan items Other Deferred tax Accumulated other comprehensive income (loss) Balance at December 31, 2014 $ (1,177 ) $ (45 ) $ 41 $ 8 $ 435 $ (738 ) Changes in fair value (525 ) (10 ) — (5 ) 200 (340 ) Reclassification to earnings 264 15 — — (104 ) 175 Balance at September 30, 2015 $ (1,438 ) $ (40 ) $ 41 $ 3 $ 531 $ (903 )
Reclassification out of Accumulated Other Comprehensive Income	The following tables illustrate the significant amounts reclassified out of each component of AOCI for the three and nine months ended September 30, 2015 : Three months ended September 30, 2015 (in millions) Amounts reclassified from AOCI Affected line item in the unaudited Condensed Consolidated Statement of Comprehensive Income AOCI components Unrealized loss on fuel derivative instruments $ 126 Fuel and oil expense 47 Less: Tax Expense $ 79 Net of tax Unrealized loss on interest rate derivative instruments $ 5 Interest expense 2 Less: Tax Expense $ 3 Net of tax Total reclassifications for the period $ 82 Net of tax Nine months ended September 30, 2015 (in millions) Amounts reclassified from AOCI Affected line item in the unaudited Condensed Consolidated Statement of Comprehensive Income AOCI components Unrealized loss on fuel derivative instruments $ 264 Fuel and oil expense 98 Less: Tax Expense $ 166 Net of tax Unrealized loss on interest rate derivative instruments $ 15 Interest expense 6 Less: Tax Expense $ 9 Net of tax Total reclassifications for the period $ 175 Net of tax

Supplemental Financial Inform18

Supplemental Financial Information (Tables)	9 Months Ended
	Sep. 30, 2015
Table Text Block [Abstract]
Other Assets	Other assets (in millions) September 30, 2015 December 31, 2014 Derivative contracts $ 6 $ 13 Intangible assets (a) 469 363 Non-current investments 40 35 Other 172 123 Other assets $ 687 $ 534 (a) Intangible assets primarily consist of acquired leasehold rights to certain airport owned gates at Chicago’s Midway International Airport, takeoff and landing slots (a “slot” is the right of an air carrier, pursuant to regulations of the Federal Aviation Administration (“FAA”), to operate a takeoff or landing at a specific time at certain airports) at certain domestic slot-controlled airports, and certain intangible assets recognized from the AirTran acquisition. The increase in Intangible assets during 2015 was primarily due to the acquisition of two additional airport gate rights at Dallas Love Field, which were subleased from United Airlines. The purchase price paid for these airport gate rights was included as a component of Capital expenditures in the accompanying unaudited Condensed Consolidated Statement of Cash Flows.
Schedule of Accounts Payable	Accounts payable (in millions) September 30, 2015 December 31, 2014 Accounts payable trade $ 170 $ 123 Salaries payable 340 160 Excise and other tax withholdings payable 157 163 Aircraft maintenance payable 162 314 Fuel payable 46 85 Other payables 360 358 Accounts payable $ 1,235 $ 1,203
Accrued Liabilities	Accrued liabilities (in millions) September 30, 2015 December 31, 2014 ProfitSharing and savings plans $ 506 $ 374 Aircraft and other lease related obligations 86 159 Vacation pay 310 292 Health 77 84 Derivative contracts 541 174 Workers compensation 181 165 Property and income taxes 129 81 Other 219 236 Accrued liabilities $ 2,049 $ 1,565
Other Noncurrent Liabilities	Other noncurrent liabilities (in millions) September 30, 2015 December 31, 2014 Postretirement obligation $ 179 $ 169 Non-current lease-related obligations 164 193 Other deferred compensation 171 174 Deferred gains from sale and leaseback of aircraft 45 53 Derivative contracts 265 622 Other 107 44 Other noncurrent liabilities $ 931 $ 1,255

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2015
Leases [Abstract]
Sublease Rollforward	A rollforward of the Company's B717 lease/sublease liability for 2015 and 2014 is shown below: (in millions) B717 lease/sublease liability Balance at December 31, 2013 $ 122 Lease/sublease accretion 5 Lease/sublease expense adjustment 22 Lease/sublease payments, net (a) (86 ) Balance at December 31, 2014 $ 63 Lease/sublease accretion 1 Lease/sublease expense adjustment 5 Lease/sublease payments, net (a) (39 ) Balance at September 30, 2015 $ 30 (a) Includes lease conversion cost payments

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Assets and liabilities measured at fair value on a recurring basis	The following tables present the Company’s assets and liabilities that are measured at fair value on a recurring basis at September 30, 2015 , and December 31, 2014 : Fair value measurements at reporting date using: Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs Description September 30, 2015 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents Cash equivalents (a) $ 1,528 $ 1,528 $ — $ — Commercial paper 125 — 125 — Certificates of deposit 25 — 25 — Eurodollar time deposits 62 — 62 — Short-term investments: Treasury bills 1,149 1,149 — — Certificates of deposit 207 — 207 — Noncurrent investments (b) Auction rate securities 27 — — 27 Interest rate derivatives 6 — 6 — Fuel derivatives: Swap contracts (c) 818 — 818 — Option contracts (c) 912 — — 912 Other available-for-sale securities 62 62 — — Total assets $ 4,921 $ 2,739 $ 1,243 $ 939 Liabilities Fuel derivatives: Swap contracts (c) $ (679 ) $ — $ (679 ) $ — Option contracts (c) (2,281 ) — — (2,281 ) Interest rate derivatives (54 ) — (54 ) — Total liabilities $ (3,014 ) $ — $ (733 ) $ (2,281 ) (a) Cash equivalents are primarily composed of money market investments. (b) Noncurrent investments are included in Other assets in the unaudited Condensed Consolidated Balance Sheet. (c) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net liability. Fair value measurements at reporting date using: Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs Description December 31, 2014 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents Cash equivalents (a) $ 1,110 $ 1,110 $ — $ — Commercial paper 70 — 70 — Certificates of deposit 4 — 4 — Eurodollar time deposits 98 — 98 — Short-term investments: Treasury bills 1,450 1,450 — — Certificates of deposit 256 — 256 — Noncurrent investments (b) Auction rate securities 27 — — 27 Interest rate derivatives 13 — 13 — Fuel derivatives: Swap contracts (c) 455 — 455 — Option contracts (c) 892 — — 892 Other available-for-sale securities 68 63 — 5 Total assets $ 4,443 $ 2,623 $ 896 $ 924 Liabilities Fuel derivatives: Swap contracts (c) $ (365 ) $ — $ (365 ) $ — Option contracts (c) (1,983 ) — — (1,983 ) Interest rate derivatives (61 ) — (61 ) — Total liabilities $ (2,409 ) $ — $ (426 ) $ (1,983 ) (a) Cash equivalents are primarily composed of money market investments. (b) Noncurrent investments are included in Other assets in the unaudited Condensed Consolidated Balance Sheet. (c) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net liability.
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation	The following tables present the Company’s activity for items measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the three and nine months ended September 30, 2015 : Fair value measurements using significant unobservable inputs (Level 3) Fuel Auction rate Other (in millions) derivatives securities securities Total Balance at June 30, 2015 $ (1,055 ) $ 27 $ — $ (1,028 ) Total losses (realized or unrealized) Included in earnings (405 ) — — (405 ) Included in other comprehensive income (488 ) — — (488 ) Purchases 408 (a) — — 408 Sales (11 ) (a) — — (11 ) Settlements 182 — — 182 Balance at September 30, 2015 $ (1,369 ) $ 27 (b) $ — $ (1,342 ) The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015 $ (317 ) $ — $ — $ (317 ) (a) The purchase and sale of fuel derivatives are recorded gross based on the structure of the derivative instrument and whether a contract with multiple derivatives is purchased as a single instrument or separate instruments. (b) Included in Other assets in the unaudited Condensed Consolidated Balance Sheet. Fair value measurements using significant unobservable inputs (Level 3) Fuel Auction rate Other (in millions) derivatives securities securities Total Balance at December 31, 2014 $ (1,091 ) $ 27 $ 5 $ (1,059 ) Total losses (realized or unrealized) Included in earnings (413 ) — (1 ) (414 ) Included in other comprehensive income (517 ) — — (517 ) Purchases 652 (a) — — 652 Sales (182 ) (a) — (4 ) (186 ) Settlements 182 — — 182 Balance at September 30, 2015 $ (1,369 ) $ 27 (b) $ — $ (1,342 ) The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015 $ (324 ) $ — $ — $ (324 ) (a) The purchase and sale of fuel derivatives are recorded gross based on the structure of the derivative instrument and whether a contract with multiple derivatives is purchased as a single instrument or separate instruments. (b) Included in Other assets in the unaudited Condensed Consolidated Balance Sheet.
Fair Value Valuation Techniques	The following table presents a range of the unobservable inputs utilized in the fair value measurements of the Company’s assets and liabilities classified as Level 3 at September 30, 2015 : Quantitative information about Level 3 fair value measurements Valuation technique Unobservable input Period (by year) Range Fuel derivatives Option model Implied volatility Fourth quarter 2015 21-41% 2016 24-41% 2017 22-34% 2018 16-29% Auction rate securities Discounted cash flow Time to principal recovery 8 years Illiquidity premium 3-4% Counterparty credit spread 1-2%
Fair value, by Balance Sheet Grouping	The carrying amounts and estimated fair values of the Company’s long-term debt (including current maturities), as well as the applicable fair value hierarchy tier, at September 30, 2015 , are presented in the table below. The fair values of the Company’s publicly held long-term debt are determined based on inputs that are readily available in public markets or can be derived from information available in publicly quoted markets; therefore, the Company has categorized these agreements as Level 2. Six of the Company’s debt agreements are not publicly held. The Company has determined the estimated fair value of this debt to be Level 3, as certain inputs used to determine the fair value of these agreements are unobservable. The Company utilizes indicative pricing from counterparties and a discounted cash flow method to estimate the fair value of the Level 3 items. (in millions) Carrying value Estimated fair value Fair value level hierarchy 5.75% Notes due 2016 $ 308 $ 324 Level 2 5.25% Convertible Senior Notes due 2016 112 294 Level 2 5.125% Notes due 2017 310 326 Level 2 French Credit Agreements due 2018 - 1.15% 31 31 Level 3 Fixed-rate 737 Aircraft Notes payable through 2018 - 7.02% 18 19 Level 3 2.75% Notes due 2019 308 313 Level 2 Term Loan Agreement due 2019 - 6.315% 152 158 Level 3 Term Loan Agreement due 2019 - 4.84% 36 38 Level 3 Term Loan Agreement due 2020 - 5.223% 340 337 Level 3 Floating-rate 737 Aircraft Notes payable through 2020 267 261 Level 3 Pass Through Certificates due 2022 - 6.24% 339 380 Level 2 7.375% Debentures due 2027 132 160 Level 2

Net Income Per Share (Tables)

Net Income Per Share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Schedule Of Earnings Per Share Basic And Diluted	The following table sets forth the computation of basic and diluted net income per share (in millions, except per share amounts): Three months ended September 30, Nine months ended September 30, 2015 2014 2015 2014 NUMERATOR: Net income $ 584 $ 329 $ 1,645 $ 946 Incremental income effect of interest on 5.25% convertible notes 1 1 3 3 Net income after assumed conversion $ 585 $ 330 $ 1,648 $ 949 DENOMINATOR: Weighted-average shares outstanding, basic 655 683 665 690 Dilutive effect of Employee stock options and restricted stock units 2 2 2 3 Dilutive effect of 5.25% convertible notes 6 6 6 6 Adjusted weighted-average shares outstanding, diluted 663 691 673 699 NET INCOME PER SHARE: Basic $ 0.89 $ 0.48 $ 2.47 $ 1.37 Diluted $ 0.88 $ 0.48 $ 2.45 $ 1.36

Accounting Changes And New Ac22

Accounting Changes And New Accounting Pronouncements (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Revenue	$ 303	$ 303
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	$ 161	$ 161
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Basic Earnings Per Share	$ 0.25	$ 0.24
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Diluted Earnings Per Share	$ 0.24	$ 0.24
Passenger Revenue
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Current Period Disclosures, Revenue Recognized, Amount	$ (40)	$ (40)
Special Revenue Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Current Period Disclosures, Revenue Recognized, Amount	172	172
Other Revenue
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Current Period Disclosures, Revenue Recognized, Amount	$ 171	$ 171

Change In Accounting Estimate (

Change In Accounting Estimate (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015
Change in Accounting Estimate [Abstract]
Change in Accounting Estimate Financial Effect on Passenger Revenue, Spoilage Estimate	$ 30	$ 115
Change in accounting estimate, financial effect on net income, spoilage adjustment	$ 16	$ 61
Change in accounting estimate,financial effect on earnings per share	$ 0.02	$ 0.09

Financial Derivative Instrume24

Financial Derivative Instruments Narrative (Details) - USD ($)		3 Months Ended		6 Months Ended	9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Feb. 10, 2015	Dec. 31, 2006
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage		43.00%			43.00%
Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge							$ 12,000,000
Amount paid for purchases and sales of offsetting derivative instruments				$ 39,000,000
Hedge settlement losses recognized in Fuel and oil expense		$ 245,000,000
Premiums paid for fuel derivative contracts		33,000,000	$ 15,000,000		$ 81,000,000	$ 49,000,000
Current Unrealized Net Gains (Losses) in OCI		(471,000,000)			(471,000,000)
Maximum sum of derivatives of counterparty to be included in other (less than $20 million)		$ 30,000,000			$ 30,000,000
Cash collateral provided as a percentage of derivative contract value (in hundredths)		100.00%			100.00%
Letter of Credit Percent of Collateral		100.00%			100.00%
5.75% Notes due 2016
Derivative [Line Items]
Debt Instrument, Face Amount								$ 300,000,000
Stated interest rate								5.75%
Cash Flow Hedging
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	[1]	$ (82,000,000)	(8,000,000)		$ (175,000,000)	(13,000,000)
Cash Flow Hedging | Fuel derivatives
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	[1],[2]	(79,000,000)	(4,000,000)		(166,000,000)	(3,000,000)
Cash Flow Hedging | Interest rate derivatives
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	[1],[2]	(3,000,000)	$ (4,000,000)		$ (9,000,000)	$ (10,000,000)
Fourth Quarter 2015 And First Half 2016
Derivative [Line Items]
Amount paid for purchases and sales of offsetting derivative instruments		$ 294,000,000
[1]	Amounts related to fuel derivative contracts and interest rate derivatives are included in Fuel and oil and Interest expense, respectively.
[2]	Net of tax

Financial Derivative Instrume25

Financial Derivative Instruments - Fuel Hedging (Details) gal in Millions	Sep. 30, 2015gal
Fourth quarter 2015
Volume of Fuel Hedging [Line Items]
Fuel Hedged (in gallons)	0	[1]
2,016
Volume of Fuel Hedging [Line Items]
Fuel Hedged (in gallons)	1,188	[2]
2,017
Volume of Fuel Hedging [Line Items]
Fuel Hedged (in gallons)	1,294	[2]
2,018
Volume of Fuel Hedging [Line Items]
Fuel Hedged (in gallons)	466	[2]
[1]	The Company is effectively unhedged for fourth quarter 2015 at current price levels. While the Company still holds derivative contracts as of September 30, 2015, that will settle during fourth quarter 2015, the losses associated with those contracts are substantially locked in. However, if market prices were to increase or decrease significantly related to the fourth quarter 2015 positions prior to these contracts settling, the losses incurred at settlement could be slightly lower or higher than currently expected amounts during that period.
[2]	Due to the types of derivatives and commodities utilized by the Company and different price levels of those contracts, this volume represents the maximum "economic" net hedge in place. The Company's average "economic" net hedge of estimated fuel consumption covered by fuel derivative contracts is lower than this maximum volume, may vary significantly as market prices fluctuate, and begins to provide hedge coverage at price levels above current market prices.

Financial Derivative Instrume26

Financial Derivative Instruments - Fair Values by Balance Sheet Location (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	$ 1,736	$ 1,360
Derivative Liability, Fair Value, Gross Liability	[1]	3,014	2,409
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	96	13
Derivative Liability, Fair Value, Gross Liability	[1]	1,064	704
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	1,640	1,347
Derivative Liability, Fair Value, Gross Liability	[1]	1,950	1,705
Fuel derivatives
Derivatives, Fair Value [Line Items]
Collateral Already Posted, Aggregate Fair Value		478
Fuel derivatives | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Collateral Already Posted, Aggregate Fair Value		15	68
Fuel derivatives | Accounts Payable Balance Sheet Location [Member]
Derivatives, Fair Value [Line Items]
Due To Third Parties For Settled Fuel Contracts		41	16
Fuel derivatives | Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Collateral Already Posted, Aggregate Fair Value		463	198
Fuel derivatives | Designated as Hedging Instrument | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	36	0
Derivative Liability, Fair Value, Gross Liability	[1]	414	0
Fuel derivatives | Designated as Hedging Instrument | Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	54	0
Derivative Liability, Fair Value, Gross Liability	[1]	596	643
Fuel derivatives | Not Designated as Hedging Instrument | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	1,358	1,190
Derivative Liability, Fair Value, Gross Liability	[1]	1,536	1,432
Fuel derivatives | Not Designated as Hedging Instrument | Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	282	157
Derivative Liability, Fair Value, Gross Liability	[1]	414	273
Interest rate derivatives | Designated as Hedging Instrument | Other Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	6	13
Derivative Liability, Fair Value, Gross Liability	[1]	0	0
Interest rate derivatives | Designated as Hedging Instrument | Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	0	0
Derivative Liability, Fair Value, Gross Liability	[1]	$ 54	$ 61
[1]	Represents the position of each trade before consideration of offsetting positions with each counterparty and does not include the impact of cash collateral deposits provided to or received from counterparties. See discussion of credit risk and collateral following in this Note.

Financial Derivative Instrume27

Financial Derivative Instruments - Offsetting of Derivative Assets (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014
Offsetting Assets [Line Items]
Asset derivative contracts, net		$ 6	$ 13
Fuel derivatives | Accrued Liabilities
Offsetting Assets [Line Items]
Gross amounts of recognized assets		1,409	1,258
Gross liability amounts offset in the Balance Sheet		(1,409)	(1,258)
Asset derivative contracts, net	[1]	0	0
Fuel derivatives | Other Noncurrent Liabilities
Offsetting Assets [Line Items]
Gross amounts of recognized assets		799	355
Gross liability amounts offset in the Balance Sheet		(799)	(355)
Asset derivative contracts, net	[1]	0	0
Interest rate derivatives | Other Assets
Offsetting Assets [Line Items]
Gross amounts of recognized assets		6	13
Gross liability amounts offset in the Balance Sheet		0	0
Asset derivative contracts, net	[1]	$ 6	$ 13
[1]	The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5.

Financial Derivative Instrume28

Financial Derivative Instruments - Offsetting of Derivative Liabilities (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014
Other Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Liability derivative contracts, net		$ 265	$ 622
Fuel derivatives | Accrued Liabilities
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities		1,950	1,432
Gross asset amounts offset in the Balance Sheet		(1,409)	(1,258)
Liability derivative contracts, net	[1]	541	174
Fuel derivatives | Other Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities		1,010	916
Gross asset amounts offset in the Balance Sheet		(799)	(355)
Liability derivative contracts, net	[1]	211	561
Interest rate derivatives | Other Noncurrent Liabilities
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities		54	61
Gross asset amounts offset in the Balance Sheet		0	0
Liability derivative contracts, net	[1]	$ 54	$ 61
[1]	The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5.

Financial Derivative Instrume29

Financial Derivative Instruments - (Gain) Loss by Hedging Relationship (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) Loss recognized in AOCI on derivatives (effective portion)		$ 318	$ 212	$ 336	$ 106
(Gain) Loss reclassified from AOCI into income (effective portion)	[1]	82	8	175	13
(Gain) Loss recognized in income on derivatives (ineffective portion)	[2]	0	9	(17)	(34)
Fuel derivatives | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) Loss recognized in AOCI on derivatives (effective portion)	[3]	315	214	330	104
(Gain) Loss reclassified from AOCI into income (effective portion)	[1],[3]	79	4	166	3
(Gain) Loss recognized in income on derivatives (ineffective portion)	[2]	0	11	(15)	(31)
Interest rate derivatives | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) Loss recognized in AOCI on derivatives (effective portion)	[3]	3	(2)	6	2
(Gain) Loss reclassified from AOCI into income (effective portion)	[1],[3]	3	4	9	10
(Gain) Loss recognized in income on derivatives (ineffective portion)	[2]	0	(2)	(2)	(3)
Other Nonoperating Income Expense | Fuel derivatives | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) loss recognized in income on derivatives		$ 239	$ 39	$ 330	$ (1)
[1]	Amounts related to fuel derivative contracts and interest rate derivatives are included in Fuel and oil and Interest expense, respectively.
[2]	Amounts are included in Other (gains) losses, net.
[3]	Net of tax

Financial Derivative Instrume30

Financial Derivative Instruments - Fair Values of Fuel Derivatives Amounts Posted as Collateral (Details) - Fuel derivatives $ in Millions	Sep. 30, 2015USD ($)
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	$ (1,230)
Cash collateral held by CP	(478)
Aircraft collateral pledged to CP	(300)
Letters of credit (LC)	0
Counterparty A
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(514)
Cash collateral held by CP	(238)
Aircraft collateral pledged to CP	(210)
Letters of credit (LC)	0
Counterparty B
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(179)
Cash collateral held by CP	(50)
Aircraft collateral pledged to CP	(90)
Letters of credit (LC)	0
Counterparty C
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(153)
Cash collateral held by CP	(39)
Aircraft collateral pledged to CP	0
Letters of credit (LC)	0
Counterparty D
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(206)
Cash collateral held by CP	(146)
Aircraft collateral pledged to CP	0
Letters of credit (LC)	0
Counterparty E
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(108)
Cash collateral held by CP	0
Aircraft collateral pledged to CP	0
Letters of credit (LC)	0
Counterparty F
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(37)
Cash collateral held by CP	(5)
Aircraft collateral pledged to CP	0
Letters of credit (LC)	0
Counterparty Other [Member]
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(33)	[1]
Cash collateral held by CP	0	[1]
Aircraft collateral pledged to CP	0	[1]
Letters of credit (LC)	0	[1]
Minimum | Counterparty A
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for aircraft	(200)	[2]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(50)
Fair value of fuel derivative levels at which cash is provided to CP Threshold 2	(600)
Fair value of fuel derivative level at which cash is received from CP	50
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(200)	[3]
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	0
Fair value of fuel derivative levels at which cash is provided to CP Threshold 2	$ (600)
Fair value of fuel derivative level at which cash is received from CP		[4]
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	$ (200)
Minimum | Counterparty B
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for aircraft	(100)	[5]
Option to substitute LC for cash Threshold 1	(500)
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(50)
Fair value of fuel derivative levels at which cash is provided to CP Threshold 2	(500)
Fair value of fuel derivative level at which cash is received from CP	150
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(100)
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	0
Fair value of fuel derivative levels at which cash is provided to CP Threshold 2	$ (500)
Fair value of fuel derivative level at which cash is received from CP		[4]
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	$ (100)
Minimum | Counterparty C
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for cash Threshold 1	(225)	[6]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(125)
Fair value of fuel derivative level at which cash is received from CP	$ 175	[7]
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1		[4]
Fair value of fuel derivative level at which cash is received from CP		[4]
Minimum | Counterparty D
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for aircraft	$ (150)	[5]
Option to substitute LC for cash Threshold 1	(75)	[5]
Option to substitute LC for cash Threshold 2	(550)	[5]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(75)
Fair value of fuel derivative levels at which cash is provided to CP Threshold 2	(550)
Fair value of fuel derivative level at which cash is received from CP	250
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(150)	[5]
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	0
Fair value of fuel derivative levels at which cash is provided to CP Threshold 2	$ (550)
Fair value of fuel derivative level at which cash is received from CP		[4]
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	$ (150)
Minimum | Counterparty E
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for cash Threshold 1		[8]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	$ (125)
Fair value of fuel derivative level at which cash is received from CP	$ 75
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1		[4]
Fair value of fuel derivative level at which cash is received from CP		[4]
Minimum | Counterparty F
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for cash Threshold 1		[8]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	$ (50)
Fair value of fuel derivative level at which cash is received from CP	$ 50
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1		[4]
Fair value of fuel derivative level at which cash is received from CP		[4]
Maximum | Counterparty A
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for aircraft	$ (600)	[2]
Option to substitute LC for cash Threshold 1		[3]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	$ (200)
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(600)	[3]
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(200)
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(600)
Maximum | Counterparty B
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for aircraft	(500)	[5]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(100)
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(500)	[5]
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(100)
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(500)
Maximum | Counterparty C
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for cash Threshold 1	(275)	[6]
Maximum | Counterparty D
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Option to substitute LC for aircraft	(550)	[5]
Option to substitute LC for cash Threshold 1	(150)	[6]
If credit rating is investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(150)
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	(550)	[5]
If credit rating is non-investment grade, fair value of fuel derivative level at which:
Fair value of fuel derivative levels at which cash is provided to CP Threshold 1	(150)
Fair value of fuel derivative levels at which aircraft or cash collateral is pledged to CP	$ (550)
[1]	Individual counterparties with fair value of fuel derivatives <$30 million.
[2]	The Company has the option of providing letters of credit in addition to aircraft collateral if the appraised value of the aircraft does not meet the collateral requirements.
[3]	The Company has the option of providing cash or pledging aircraft as collateral.
[4]	Cash collateral is provided at 100 percent of fair value of fuel derivative contracts.
[5]	The Company has the option of providing cash, letters of credit, or pledging aircraft as collateral.
[6]	The Company has the option of providing cash or letters of credit as collateral.
[7]	Thresholds may vary based on changes in credit ratings within investment grade.
[8]	The Company has the option to substitute letters of credit for 100 percent of cash collateral requirement.

Comprehensive Income (Details)

Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Net income	$ 584	$ 329	$ 1,645	$ 946
Other, net of deferred taxes	(3)	1	(4)	4
Total other comprehensive income (loss)	(239)	(203)	(165)	(89)
Total comprehensive income	345	126	1,480	857
Deferred taxes on unrealized gain (loss) on other	(2)	1	(1)	4
AOCI Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income Loss [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(903)		(903)		$ (664)	$ (738)
Reclassification to earnings	82		175
Changes in fair value	(321)		(340)
Fuel derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(1,438)		(1,438)		(1,063)	(1,177)
Reclassification to earnings	126		264
Changes in fair value	(501)		(525)
Interest rate derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(40)		(40)		(40)	(45)
Reclassification to earnings	5		15
Changes in fair value	(5)		(10)
Defined benefit plan items
Accumulated Other Comprehensive Income Loss [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	41		41		41	41
Reclassification to earnings	0		0
Changes in fair value	0		0
Other
Accumulated Other Comprehensive Income Loss [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	3		3		8	8
Reclassification to earnings	0		0
Changes in fair value	(5)		(5)
Deferred tax
Accumulated Other Comprehensive Income Loss [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	531		531		$ 390	$ 435
Reclassification to earnings	(49)		(104)
Changes in fair value	190		200
Interest rate derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Unrealized gain (loss) on derivatives, net of tax	0	6	3	8
Deferred taxes on unrealized gain (loss) on derivatives	0	3	2	4
Fuel derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Unrealized gain (loss) on derivatives, net of tax	(236)	(210)	(164)	(101)
Deferred taxes on unrealized gain (loss) on derivatives	$ (139)	$ (124)	$ (97)	$ (60)

Comprehensive Income - Reclassi

Comprehensive Income - Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Fuel and oil	$ (936)	$ (1,386)	$ (2,818)	$ (4,125)
Less: Tax Expense	349	$ 196	987	$ 569
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Net of Tax	82		175
Fuel derivatives | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Fuel and oil	126		264
Less: Tax Expense	47		98
Net of Tax	79		166
Interest rate derivatives | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Interest Expense	5		15
Less: Tax Expense	2		6
Net of Tax	$ 3		$ 9

Supplemental Financial Inform33

Supplemental Financial Information - Other Assets (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014
Other Assets [Abstract]
Asset derivative contracts, net		$ 6	$ 13
Intangible assets	[1]	469	363
Non-current investments		40	35
Other		172	123
Other assets		687	534
Accrued Liabilities | Fuel derivatives
Other Assets [Abstract]
Asset derivative contracts, net	[2]	0	0
Other Assets | Interest rate derivatives
Other Assets [Abstract]
Asset derivative contracts, net	[2]	$ 6	$ 13
[1]	Intangible assets primarily consist of acquired leasehold rights to certain airport owned gates at Chicago’s Midway International Airport, takeoff and landing slots (a “slot” is the right of an air carrier, pursuant to regulations of the Federal Aviation Administration (“FAA”), to operate a takeoff or landing at a specific time at certain airports) at certain domestic slot-controlled airports, and certain intangible assets recognized from the AirTran acquisition. The increase in Intangible assets during 2015 was primarily due to the acquisition of two additional airport gate rights at Dallas Love Field, which were subleased from United Airlines. The purchase price paid for these airport gate rights was included as a component of Capital expenditures in the accompanying unaudited Condensed Consolidated Statement of Cash Flows.
[2]	The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5.

Supplemental Financial Inform34

Supplemental Financial Information - Accounts Payable (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Supplemental Financial Information - Accounts Payable [Abstract]
Accounts payable trade	$ 170	$ 123
Salaries payable	340	160
Excise and other tax withholdings payable	157	163
Aircraft Maintenance Payable	162	314
Fuel Payable	46	85
Other payables	360	358
Accounts Payable, Current	$ 1,235	$ 1,203

Supplemental Financial Inform35

Supplemental Financial Information - Accrued Liabilities (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014
Accrued Liabilities, Current [Abstract]
ProfitSharing and savings plans		$ 506	$ 374
Aircraft and other lease related obligations		86	159
Vacation pay		310	292
Health		77	84
Workers compensation		181	165
Property and income taxes		129	81
Other		219	236
Accrued liabilities		2,049	1,565
Fuel derivatives | Accrued Liabilities
Accrued Liabilities, Current [Abstract]
Liability derivative contracts, net	[1]	$ 541	$ 174
[1]	The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5.

Supplemental Financial Inform36

Supplemental Financial Information - Other Non-Current Liabilities (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014
Other Liabilities, Noncurrent [Abstract]
Postretirement obligation		$ 179	$ 169
Non-current lease-related obligations		164	193
Other deferred compensation		171	174
Deferred gains from sale and leaseback of aircraft		45	53
Other		107	44
Other noncurrent liabilities		931	1,255
Other Noncurrent Liabilities
Other Liabilities, Noncurrent [Abstract]
Liability derivative contracts, net		265	622
Fuel derivatives | Other Noncurrent Liabilities
Other Liabilities, Noncurrent [Abstract]
Liability derivative contracts, net	[1]	211	561
Interest rate derivatives | Other Noncurrent Liabilities
Other Liabilities, Noncurrent [Abstract]
Liability derivative contracts, net	[1]	$ 54	$ 61
[1]	The net amounts of derivative assets and liabilities are reconciled to the individual line item amounts presented in the unaudited Condensed Consolidated Balance Sheet in Note 5.

Leases (Details)

Leases (Details) - B-717-200 Aircraft	3 Months Ended
	Sep. 30, 2015USD ($)aircraft	Sep. 30, 2012USD ($)	Jul. 09, 2012aircraft
Aircraft Type [Line Items]
Lessee	Delta Air Lines, Inc.
Total assets available for lease/sublease, number of units			88
Number of aircraft delivered to sublessee	80
Remaining number of aircraft to be delivered to sublessee	8
Operating lease, number of units	76
Owned assets, number of units	10
Capital leased assets, number of units	2
Contingent payments | $	$ 0
Residual value | $	$ 0
Estimated loss on sublease | $		$ 137,000,000
Operating Lease [Member]
Aircraft Type [Line Items]
Number of aircraft delivered to sublessee	73
Sales Type Lease [Member]
Aircraft Type [Line Items]
Number of aircraft delivered to sublessee	5
Direct Financing Lease [Member]
Aircraft Type [Line Items]
Number of aircraft delivered to sublessee	2
Maximum
Aircraft Type [Line Items]
Sublease terms for leased aircraft	9 years
Lease terms for owned aircraft	7 years
Minimum
Aircraft Type [Line Items]
Sublease terms for leased aircraft	3 years

Sublease Table (Details)

Sublease Table (Details) - B-717-200 Aircraft - USD ($) $ in Millions		9 Months Ended	12 Months Ended
		Sep. 30, 2015	Dec. 31, 2014	Dec. 31, 2013
B717 Sublease Liability [Line Items]
Sublease Obligations		$ 30	$ 63	$ 122
Interest Expense, Accretion		1	5
Additional Estimated Loss on Sublease		5	22
Sublease Transaction Costs	[1]	$ (39)	$ (86)
[1]	Includes lease conversion cost payments

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2012	Dec. 31, 2010	Sep. 30, 2015	Dec. 31, 2014
Airport Project [Line Items]
Assets constructed for others			$ 823	$ 621
Construction obligation			684	$ 554
Fort Lauderdale-Hollywood International Airport
Airport Project [Line Items]
Total Expected Cost Of Airport Project			295
Assets constructed for others			17
HOU
Airport Project [Line Items]
Total Expected Cost Of Airport Project			156
Assets constructed for others			128
Los Angeles World Airport
Airport Project [Line Items]
Total Expected Cost Of Airport Project			526
Assets constructed for others			151
Construction obligation			151
DAL
Airport Project [Line Items]
Assets constructed for others			527
Municipal bonds issued	$ 146	$ 310
Construction obligation			$ 516

Fair Value Measurements Narrati

Fair Value Measurements Narrative (Details) $ in Millions	Sep. 30, 2015USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	$ 27

Fair Value Measurements - Measu

Fair Value Measurements - Measured on Recurring Basis (Details) - USD ($) $ in Millions		3 Months Ended
		Sep. 30, 2015		Dec. 31, 2012	Dec. 31, 2014
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset	[1]	$ 1,736			$ 1,360
Fuel derivatives:
Derivative Liability, Fair Value, Gross Liability	[1]	(3,014)			(2,409)
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount		0			0
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount		0			0
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount		0			0
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount		0			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net		0		$ 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers, Net		0		$ 0
Fair Value, Measurements, Recurring | Period end date
Assets
Treasury bills		1,149			1,450
Interest rate derivatives		6			13
Other available for sale securities		62			68
Total assets		4,921			4,443
Liabilities
Interest rate derivatives		(54)			(61)
Total Liabilities		(3,014)			(2,409)
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Treasury bills		1,149			1,450
Interest rate derivatives		0			0
Other available for sale securities		62			63
Total assets		2,739			2,623
Liabilities
Interest rate derivatives		0			0
Total Liabilities		0			0
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Treasury bills		0			0
Interest rate derivatives		6			13
Other available for sale securities		0			0
Total assets		1,243			896
Liabilities
Interest rate derivatives		(54)			(61)
Total Liabilities		(733)			(426)
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Treasury bills		0			0
Interest rate derivatives		0			0
Other available for sale securities		0			5
Total assets		939			924
Liabilities
Interest rate derivatives		0			0
Total Liabilities		(2,281)			(1,983)
Cash Equivalents | Fair Value, Measurements, Recurring | Period end date
Assets
Cash equivalents		1,528	[2]		1,110	[3]
Cash Equivalents | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Cash equivalents		1,528	[2]		1,110	[3]
Cash Equivalents | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Cash equivalents		0	[2]		0	[3]
Cash Equivalents | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Cash equivalents		0	[2]		0	[3]
Commercial paper | Fair Value, Measurements, Recurring | Period end date
Assets
Cash equivalents		125			70
Commercial paper | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Cash equivalents		0			0
Commercial paper | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Cash equivalents		125			70
Commercial paper | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Cash equivalents		0			0
Certificates of deposit | Fair Value, Measurements, Recurring | Period end date
Assets
Cash equivalents		25			4
Certificates of deposit | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Cash equivalents		0			0
Certificates of deposit | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Cash equivalents		25			4
Certificates of deposit | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Cash equivalents		0			0
Eurodollar time deposits | Fair Value, Measurements, Recurring | Period end date
Assets
Cash equivalents		62			98
Eurodollar time deposits | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Cash equivalents		0			0
Eurodollar time deposits | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Cash equivalents		62			98
Eurodollar time deposits | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Cash equivalents		0			0
Certificates of deposit | Fair Value, Measurements, Recurring | Period end date
Assets
Investments		207			256
Certificates of deposit | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Investments		0			0
Certificates of deposit | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Investments		207			256
Certificates of deposit | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Investments		0			0
Auction rate securities | Fair Value, Measurements, Recurring | Period end date
Assets
Investments		27	[4]		27	[5]
Auction rate securities | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Investments		0	[4]		0	[5]
Auction rate securities | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Investments		0	[4]		0	[5]
Auction rate securities | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Investments		27	[4]		27	[5]
Swap | Fair Value, Measurements, Recurring | Period end date
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		818	[6]		455	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		(679)	[6]		(365)	[7]
Swap | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		0	[6]		0	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		0	[6]		0	[7]
Swap | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		818	[6]		455	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		(679)	[6]		(365)	[7]
Swap | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		0	[6]		0	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		0	[6]		0	[7]
Options Held | Fair Value, Measurements, Recurring | Period end date
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		912	[6]		892	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		(2,281)	[6]		(1,983)	[7]
Options Held | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		0	[6]		0	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		0	[6]		0	[7]
Options Held | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		0	[6]		0	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		0	[6]		0	[7]
Options Held | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Fuel derivatives:
Derivative Asset, Fair Value, Gross Asset		912	[6]		892	[7]
Fuel derivatives:
Derivative Asset, Fair Value, Gross Liability		$ (2,281)	[6]		$ (1,983)	[7]
[1]	Represents the position of each trade before consideration of offsetting positions with each counterparty and does not include the impact of cash collateral deposits provided to or received from counterparties. See discussion of credit risk and collateral following in this Note.
[2]	Cash equivalents are primarily composed of money market investments.
[3]	Cash equivalents are primarily composed of money market investments.
[4]	Noncurrent investments are included in Other assets in the unaudited Condensed Consolidated Balance Sheet.
[5]	Noncurrent investments are included in Other assets in the unaudited Condensed Consolidated Balance Sheet.
[6]	In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net liability.
[7]	In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net liability.

Fair Value Measurement - Fair V

Fair Value Measurement - Fair Value Assets and Liabilities Measured on Recurring Basis with Unobservable Inputs (Details) - USD ($) $ in Millions		3 Months Ended	9 Months Ended
		Sep. 30, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value		$ (1,342)	$ (1,342)	$ (1,028)	$ (1,059)
Total gains or (losses) (realized or unrealized)
Included in earnings		405	414
Included in other comprehensive income		(488)	(517)
Purchases		408	652
Sales		(11)	(186)
Settlements		(182)	(182)
The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015		(317)	(324)
Fuel derivatives
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value		(1,369)	(1,369)	$ (1,055)	$ (1,091)
Total gains or (losses) (realized or unrealized)
Included in earnings		405	413
Included in other comprehensive income		(488)	(517)
Purchases	[1]	408	652
Sales	[1]	(11)	(182)
Settlements		(182)	(182)
The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015		(317)	(324)
Auction rate securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance		27	27
Total gains or (losses) (realized or unrealized)
Included in earnings		0	0
Included in other comprehensive income		0	0
Purchases		0	0
Sales		0	0
Settlements		0	0
September 30, 2015	[2]	27	27
The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015		0	0
Other securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance		0	5
Total gains or (losses) (realized or unrealized)
Included in earnings		0	1
Included in other comprehensive income		0	0
Purchases		0	0
Sales		0	(4)
Settlements		0	0
September 30, 2015		0	0
The amount of total losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at September 30, 2015		$ 0	$ 0
[1]	The purchase and sale of fuel derivatives are recorded gross based on the structure of the derivative instrument and whether a contract with multiple derivatives is purchased as a single instrument or separate instruments.
[2]	Included in Other assets in the unaudited Condensed Consolidated Balance Sheet.

Fair Value Measurements - Quant

Fair Value Measurements - Quantative Information about Level 3 Fair Value (Details)	3 Months Ended
	Sep. 30, 2015
Discounted Cash Flow | Illiquidity Premium | Auction rate securities
Quantitative Information About Level 3 [Line Items]
Fair Value Measurement Range, Minimum	3.00%
Fair Value Measurement Range, Maximum	4.00%
Discounted Cash Flow | Counterparty Credit Spread | Auction rate securities
Quantitative Information About Level 3 [Line Items]
Fair Value Measurement Range, Minimum	1.00%
Fair Value Measurement Range, Maximum	2.00%
Discounted Cash Flow | Time To Principal Recovery | Auction rate securities
Quantitative Information About Level 3 [Line Items]
Fair Value Measurement Range Min, Term	8 years
Fourth Quarter of 2015 | Option Model | Implied Volatility | Fuel derivatives
Quantitative Information About Level 3 [Line Items]
Fair Value Measurement Range, Minimum	21.00%
Fair Value Measurement Range, Maximum	41.00%
2016 | Option Model | Implied Volatility | Fuel derivatives
Quantitative Information About Level 3 [Line Items]
Fair Value Measurement Range, Minimum	24.00%
Fair Value Measurement Range, Maximum	41.00%
2017 | Option Model | Implied Volatility | Fuel derivatives
Quantitative Information About Level 3 [Line Items]
Fair Value Measurement Range, Minimum	22.00%
Fair Value Measurement Range, Maximum	34.00%
2018 | Option Model | Implied Volatility | Fuel derivatives
Quantitative Information About Level 3 [Line Items]
Fair Value Measurement Range, Minimum	16.00%
Fair Value Measurement Range, Maximum	29.00%

Fair Value Instruments - Carryi

Fair Value Instruments - Carrying and Estimated Fair Value of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2006
5.75% Notes due 2016
Debt Instrument [Line Items]
Stated interest rate		5.75%
5.75% Notes due 2016 | Unsecured Debt
Debt Instrument [Line Items]
Carrying amount of debt	$ 308
Stated interest rate	5.75%
5.25% Convertible Senior Notes due 2016 | Convertible Debt
Debt Instrument [Line Items]
Carrying amount of debt	$ 112
Stated interest rate	5.25%
5.125% Notes due 2017 | Unsecured Debt
Debt Instrument [Line Items]
Carrying amount of debt	$ 310
Stated interest rate	5.125%
French Credit Agreements due 2018 - 1.15% | Notes Payable to Banks
Debt Instrument [Line Items]
Carrying amount of debt	$ 31
Stated interest rate	1.15%
Fixed-rate 737 Aircraft Notes payable through 2018 - 7.02% | Notes Payable to Banks
Debt Instrument [Line Items]
Carrying amount of debt	$ 18
Stated interest rate	7.02%
2.75% Notes Due 2019 | Unsecured Debt
Debt Instrument [Line Items]
Carrying amount of debt	$ 308
Stated interest rate	2.75%
Term Loan Agreement due 2019 - 6.315% | Notes Payable to Banks
Debt Instrument [Line Items]
Carrying amount of debt	$ 152
Stated interest rate	6.315%
Term Loan Agreement due 2019 - 4.84% | Notes Payable to Banks
Debt Instrument [Line Items]
Carrying amount of debt	$ 36
Stated interest rate	4.84%
Term Loan Agreement due 2020 - 5.223% | Notes Payable to Banks
Debt Instrument [Line Items]
Carrying amount of debt	$ 340
Stated interest rate	5.223%
Floating-rate 737 Aircraft Notes payable through 2020 | Notes Payable to Banks
Debt Instrument [Line Items]
Carrying amount of debt	$ 267
Pass Through Certificates due 2022 - 6.24% | Enhanced Equipment Trust Certificate
Debt Instrument [Line Items]
Carrying amount of debt	$ 339
Stated interest rate	6.24%
7.375% Debentures due 2027 | Unsecured Debt
Debt Instrument [Line Items]
Carrying amount of debt	$ 132
Stated interest rate	7.375%
Level 2 | 5.75% Notes due 2016 | Unsecured Debt
Debt Instrument [Line Items]
Notes Payable, Fair Value	$ 324
Level 2 | 5.25% Convertible Senior Notes due 2016 | Convertible Debt
Debt Instrument [Line Items]
Notes Payable, Fair Value	294
Level 2 | 5.125% Notes due 2017 | Unsecured Debt
Debt Instrument [Line Items]
Notes Payable, Fair Value	326
Level 2 | 2.75% Notes Due 2019 | Unsecured Debt
Debt Instrument [Line Items]
Notes Payable, Fair Value	313
Level 2 | Pass Through Certificates due 2022 - 6.24% | Enhanced Equipment Trust Certificate
Debt Instrument [Line Items]
Notes Payable, Fair Value	380
Level 2 | 7.375% Debentures due 2027 | Unsecured Debt
Debt Instrument [Line Items]
Loans Payable, Fair Value	160
Level 3 | French Credit Agreements due 2018 - 1.15% | Notes Payable to Banks
Debt Instrument [Line Items]
Notes Payable, Fair Value	31
Level 3 | Fixed-rate 737 Aircraft Notes payable through 2018 - 7.02% | Notes Payable to Banks
Debt Instrument [Line Items]
Notes Payable, Fair Value	19
Level 3 | Term Loan Agreement due 2019 - 6.315% | Notes Payable to Banks
Debt Instrument [Line Items]
Loans Payable, Fair Value	158
Level 3 | Term Loan Agreement due 2019 - 4.84% | Notes Payable to Banks
Debt Instrument [Line Items]
Loans Payable, Fair Value	38
Level 3 | Term Loan Agreement due 2020 - 5.223% | Notes Payable to Banks
Debt Instrument [Line Items]
Loans Payable, Fair Value	337
Level 3 | Floating-rate 737 Aircraft Notes payable through 2020 | Notes Payable to Banks
Debt Instrument [Line Items]
Notes Payable, Fair Value	$ 261

Net Income Per Share (Details)

Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
NUMERATOR:
Net income	$ 584	$ 329	$ 1,645	$ 946
Incremental income effect of interest on 5.25% convertible notes	1	1	3	3
Net income after assumed conversion	$ 585	$ 330	$ 1,648	$ 949
DENOMINATOR:
Weighted-average shares outstanding, basic	655	683	665	690
Dilutive effect of Employee stock options and restricted stock units	2	2	2	3
Dilutive effect of 5.25% convertible notes	6	6	6	6
Adjusted weighted-average shares outstanding, diluted	663	691	673	699
NET INCOME PER SHARE:
Basic	$ 0.89	$ 0.48	$ 2.47	$ 1.37
Diluted	$ 0.88	$ 0.48	$ 2.45	$ 1.36