Southwest Airlines (LUV) 10-Q 26 Jul 24 2024 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Jun. 30, 2024	Jul. 25, 2024
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	1-7259
Entity Registrant Name	SOUTHWEST AIRLINES CO.
Entity Incorporation, State or Country Code	TX
Entity Tax Identification Number	74-1563240
Entity Address, Address Line One	P.O. Box 36611
Entity Address, City or Town	Dallas,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75235-1611
City Area Code	214
Local Phone Number	792-4000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		599,157,019
Entity Central Index Key	0000092380
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q2
Amendment Flag	false
Common Stock
Document Information [Line Items]
Title of 12(b) Security	Common Stock ($1.00 par value)
Trading Symbol	LUV
Security Exchange Name	NYSE
Common Stock Purchase Rights
Document Information [Line Items]
Title of 12(b) Security	Common Stock Purchase Rights
Security Exchange Name	NYSE
No Trading Symbol Flag	true

Condensed Consolidated Balance

Condensed Consolidated Balance Sheet - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 8,142	$ 9,288
Short-term investments	1,860	2,186
Accounts and other receivables	1,346	1,154
Inventories of parts and supplies, at cost	784	807
Prepaid expenses and other current assets	619	520
Total current assets	12,751	13,955
Property and equipment, at cost:
Flight equipment	26,274	26,060
Ground property and equipment	7,704	7,460
Deposits on flight equipment purchase contracts	466	236
Assets constructed for others	77	62
Property and equipment, at cost	34,521	33,818
Less allowance for depreciation and amortization	14,856	14,443
Property and equipment, net	19,665	19,375
Goodwill	970	970
Operating lease right-of-use assets	1,132	1,223
Other assets	1,045	964
Total assets	35,563	36,487
Current liabilities:
Accounts payable	2,028	1,862
Accrued liabilities	1,870	3,606
Current operating lease liabilities	198	208
Air traffic liability	7,086	6,551
Current maturities of long-term debt	2,931	29
Total current liabilities	14,113	12,256
Long-term debt less current maturities	5,065	7,978
Air traffic liability - noncurrent	1,990	1,728
Deferred income taxes	2,089	2,044
Noncurrent operating lease liabilities	915	985
Other noncurrent liabilities	926	981
Stockholders' equity:
Common stock	888	888
Capital in excess of par value	4,151	4,153
Retained earnings	16,218	16,297
Accumulated other comprehensive income	11	0
Treasury stock, at cost	(10,803)	(10,823)
Total stockholders' equity	10,465	10,515
Total liabilities and stockholders' equity	$ 35,563	$ 36,487

Condensed Consolidated Statemen

Condensed Consolidated Statement of Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
OPERATING REVENUES:
Total operating revenues	$ 7,354	$ 7,037	$ 13,683	$ 12,743
OPERATING EXPENSES:
Salaries, wages, and benefits	2,999	2,786	5,939	5,264
Fuel and oil	1,599	1,403	3,130	2,950
Maintenance materials and repairs	350	271	711	511
Landing fees and airport rentals	511	459	975	867
Depreciation and amortization	404	367	812	731
Other operating expenses	1,093	956	2,110	1,909
Total operating expenses	6,956	6,242	13,677	12,232
OPERATING INCOME	398	795	6	511
OTHER EXPENSES (INCOME):
Interest expense	63	65	128	130
Capitalized interest	(8)	(5)	(15)	(11)
Interest income	(130)	(144)	(271)	(269)
Other gains, net	(5)	(7)	(17)	(21)
Total other income	(80)	(91)	(175)	(171)
INCOME BEFORE INCOME TAXES	478	886	181	682
PROVISION FOR INCOME TAXES	111	203	44	158
NET INCOME	$ 367	$ 683	$ 137	$ 524
Net income per share, basic (in USD per share)	$ 0.61	$ 1.15	$ 0.23	$ 0.88
Net income per share, diluted (in USD per share)	$ 0.58	$ 1.08	$ 0.23	$ 0.84
COMPREHENSIVE INCOME	$ 359	$ 544	$ 148	$ 238
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (in shares)	599	595	598	595
Diluted (in shares)	643	639	643	639
Passenger
OPERATING REVENUES:
Total operating revenues	$ 6,712	$ 6,409	$ 12,424	$ 11,514
Freight
OPERATING REVENUES:
Total operating revenues	45	47	87	87
Other
OPERATING REVENUES:
Total operating revenues	$ 597	$ 581	$ 1,172	$ 1,142

Condensed Consolidated Statem_2

Condensed Consolidated Statement of Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock	Capital in excess of par value	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock
Balance at beginning of period at Dec. 31, 2022	$ 10,687	$ 888	$ 4,037	$ 16,261	$ 344	$ (10,843)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common and treasury stock pursuant to Employee stock plans	8		1			7
Share-based compensation	20		20
Cash dividends, $0.18 per share	(107)			(107)
Comprehensive income (loss)	(306)			(159)	(147)
Balance at end of period at Mar. 31, 2023	10,302	888	4,058	15,995	197	(10,836)
Balance at beginning of period at Dec. 31, 2022	10,687	888	4,037	16,261	344	(10,843)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	238
Balance at end of period at Jun. 30, 2023	10,789	888	4,103	16,571	58	(10,831)
Balance at beginning of period at Mar. 31, 2023	10,302	888	4,058	15,995	197	(10,836)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common and treasury stock pursuant to Employee stock plans	16		11			5
Share-based compensation	34		34
Cash dividends, $0.18 per share	(107)			(107)
Comprehensive income (loss)	544			683	(139)
Balance at end of period at Jun. 30, 2023	10,789	888	4,103	16,571	58	(10,831)
Balance at beginning of period at Dec. 31, 2023	10,515	888	4,153	16,297	0	(10,823)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common and treasury stock pursuant to Employee stock plans	(10)		(25)			15
Share-based compensation	10		10
Cash dividends, $0.18 per share	(107)			(107)
Comprehensive income (loss)	(212)			(231)	19
Balance at end of period at Mar. 31, 2024	10,196	888	4,138	15,959	19	(10,808)
Balance at beginning of period at Dec. 31, 2023	10,515	888	4,153	16,297	0	(10,823)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	148
Balance at end of period at Jun. 30, 2024	10,465	888	4,151	16,218	11	(10,803)
Balance at beginning of period at Mar. 31, 2024	10,196	888	4,138	15,959	19	(10,808)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common and treasury stock pursuant to Employee stock plans	17		12			5
Share-based compensation	7		7
Cash dividends, $0.18 per share	(108)			(108)
Stock warrants repurchase	(6)		(6)
Comprehensive income (loss)	359			367	(8)
Balance at end of period at Jun. 30, 2024	$ 10,465	$ 888	$ 4,151	$ 16,218	$ 11	$ (10,803)

Condensed Consolidated Statem_3

Condensed Consolidated Statement of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023
Statement of Stockholders' Equity [Abstract]
Cash dividends, per share (in USD per share)	$ 0.18	$ 0.18	$ 0.18	$ 0.18

Condensed Consolidated Statem_4

Condensed Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 367	$ 683	$ 137	$ 524
Adjustments to reconcile net loss to cash provided by (used in) operating activities:
Depreciation and amortization	404	367	812	731
Unrealized mark-to-market adjustment on available for sale securities	0	0	0	(4)
Unrealized/realized loss on fuel derivative instruments	1	6	2	6
Deferred income taxes	110	209	43	157
Changes in certain assets and liabilities:
Accounts and other receivables	34	44	(274)	(188)
Other assets	32	58	18	109
Accounts payable and accrued liabilities	(576)	364	(1,473)	293
Air traffic liability	(317)	(137)	798	809
Other liabilities	(45)	(44)	(117)	(90)
Cash collateral provided to derivative counterparties	(20)	(16)	(20)	(46)
Other, net	(13)	(118)	(54)	(178)
Net cash provided by (used in) operating activities	(23)	1,416	(128)	2,123
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(494)	(925)	(1,077)	(1,971)
Assets constructed for others	(6)	(8)	(16)	(14)
Purchases of short-term investments	(1,532)	(1,522)	(3,210)	(3,727)
Proceeds from sales of short-term and other investments	1,820	1,828	3,540	3,508
Other, net	6	0	(28)	0
Net cash used in investing activities	(206)	(627)	(791)	(2,204)
CASH FLOWS FROM FINANCING ACTIVITIES:
Payroll Support Program stock warrants repurchase	(6)	0	(6)	0
Proceeds from Employee stock plans	15	14	30	22
Payments of long-term debt and finance lease obligations	(8)	(8)	(16)	(67)
Payments of cash dividends	0	0	(215)	(214)
Other, net	3	4	(20)	6
Net cash provided by (used in) financing activities	4	10	(227)	(253)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(225)	799	(1,146)	(334)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	8,367	8,359	9,288	9,492
CASH AND CASH EQUIVALENTS AT END OF PERIOD	8,142	9,158	8,142	9,158
CASH PAYMENTS FOR:
Interest, net of amount capitalized	92	96	110	115
Income taxes	4	6	7	8
SUPPLEMENTAL DISCLOSURE OF NON-CASH TRANSACTIONS:
Right-of-use assets acquired under operating leases	$ 6	$ 22	$ 21	$ 69

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
BASIS OF PRESENTATION	BASIS OF PRESENTATION Southwest Airlines Co. (the "Company" or "Southwest") 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. In late December 2022, the Company experienced a wide-scale operational disruption as extreme winter weather across a significant portion of the United States impacted its operational plan and flight schedules. Subsequent to Winter Storm Elliott, the Company was challenged to realign flight crews, flight schedules, and aircraft for a period of several days during this peak demand travel period. This disruption and subsequent recovery efforts resulted in the cancellation of more than 16,700 flights during the period from December 21 through December 31, 2022. These events also created a deceleration in bookings, primarily isolated to January and February 2023, as well as increased first quarter 2023 expenses by approximately $55 million, which are included in the accompanying unaudited Condensed Consolidated Statement of Comprehensive Income for the six months ended June 30, 2023. These first quarter 2023 expenses included reimbursements to Customers impacted by the cancellations for costs they incurred in excess of the amounts accrued as of December 31, 2022, adjustments to the estimated value of Rapid Rewards points offered as a gesture of goodwill to Customers as a result of changes in the estimates of the points expected to be redeemed, and additional premium pay and additional compensation for Employees directly or indirectly impacted by the cancellations and recovery efforts. Based on the Company's wide-scale operational disruption, the Company has been subject to inquiries and investigations by governmental agencies (including with respect to a December 2023 settlement with the Department of Transportation) and could be subject to fines and/or penalties resulting from those inquiries and investigations, as well as litigation from Customers and Shareholders. 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 June 30, 2024 and 2023 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 performed 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 and changes in consumer behavior, unemployment levels, corporate travel budgets, global pandemics, extreme or severe weather and natural disasters, fears of terrorism or war, governmental actions, 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, and the periodic volatility of commodities used by the Company for hedging jet fuel, 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 fuel hedging program. Operating results for the three and six months ended June 30, 2024, are not necessarily indicative of the results that may be expected for future quarters or for the year ended December 31, 2024. For further information, refer to the Consolidated Financial Statements and footnotes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2023. During second quarter 2024, the Company identified certain 737-700 ("-700") aircraft that are planned for early retirement in 2025. These accelerated retirement dates, and the corresponding impact to depreciation expense, are considered a change in estimate and resulted in the following impact to Depreciation and amortization expense for the three and six months ended June 30, 2024: Three months ended Six months ended (in millions, except per share amounts) June 30, 2024 June 30, 2024 Depreciation and amortization expense $ 10 $ 10 Net income * $ (6) $ (6) Net income per basic share $ (0.01) $ (0.01) Net income per diluted share $ (0.01) $ (0.01) * net of profitsharing benefit and income taxes

New Accounting Pronouncements

New Accounting Pronouncements	6 Months Ended
	Jun. 30, 2024
Accounting Standards Update and Change in Accounting Principle [Abstract]
NEW ACCOUNTING PRONOUNCEMENTS	NEW ACCOUNTING PRONOUNCEMENTS On December 14, 2023, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update ("ASU") 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This standard increases transparency and decision usefulness of income tax disclosures for investors by requiring information to better assess how an entity's operations and related tax risks and tax planning and operational opportunities affect its tax rate and prospects for future cash flows. This standard requires entities to provide enhanced disclosures related to the income tax rate reconciliation and income taxes paid. This standard is effective for all entities that are subject to Topic 740, Income Taxes for annual periods beginning after December 15, 2024, but early adoption is permitted. The Company is evaluating this new standard but does not expect it to have a significant impact on its financial statement presentation or results. On November 27, 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This standard improves reportable segment disclosures by adding and enhancing interim disclosure requirements, clarifying circumstances in which entities can disclose multiple segment measures of profit or loss, providing new segment disclosure requirements for entities with a single reportable segment, and adding other disclosure requirements. This standard is effective for all entities that are subject to Topic 280, Segment Reporting for annual periods beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, but early adoption is permitted. The Company is evaluating this new standard but does not expect it to have a significant impact on its financial statement presentation or results.

Financial Derivative Instrument

Financial Derivative Instruments	6 Months Ended
	Jun. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
FINANCIAL DERIVATIVE INSTRUMENTS	(100) >(50) >(75) >(125) >(40) >(65) >(100) >(100) Cash is received from CP >0(b) >150(b) >250(b) >125(b) >100(b) >70(b) >100(b) >100(b) If credit rating is non-investment Cash is received from CP (c) (c) (c) (c) (c) (c) (c) (c) (a) The Company has the option to substitute letters of credit for 100 percent of cash collateral requirement. (b) Thresholds may vary based on changes in credit ratings within investment grade. (c) Cash collateral is provided at 100 percent of fair value of fuel derivative contracts." 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 typically represents one of the largest operating expenses for airlines. The Company endeavors to acquire jet fuel at the lowest possible net cost and to reduce volatility in operating expenses through its fuel hedging program. The Company has used financial derivative instruments for both short-term and long-term timeframes, and historically has used 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. The Company does not purchase or hold any financial derivative instruments for trading or speculative purposes. For the purpose of evaluating its net cash spend for jet fuel and for forecasting its future estimated jet fuel expense, 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 the Company defines as prices significantly higher than historical average levels), 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. As of June 30, 2024, the Company had fuel derivative instruments in place to provide coverage at varying price levels. The following table provides information about the Company’s volume of fuel hedged on an economic basis: Maximum fuel hedged as of June 30, 2024 Derivative underlying commodity type as of Period (by year) (gallons in millions) (a) June 30, 2024 Remainder of 2024 633 West Texas Intermediate ("WTI") crude oil, Brent crude oil, and Heating oil 2025 1,033 Brent crude oil 2026 832 Brent crude oil (a) Due to the types of derivatives utilized by the Company and different price levels of those contracts, these volumes represent the maximum economic hedge in place and may vary significantly as market prices fluctuate and if the Company's published flight schedule or capacity plans change. Upon proper qualification, the Company accounts for its fuel derivative instruments as cash flow hedges. Qualification is re-evaluated quarterly, and all periodic changes in fair value of the derivatives designated as hedges are recorded in Accumulated other comprehensive income ("AOCI") until the underlying jet fuel is consumed. See Note 4. When the Company has sold derivative positions in order to effectively "close" or offset a derivative already held as part of its fuel hedging portfolio, any subsequent changes in fair value of those positions are marked to market through the unaudited Condensed Consolidated Statement of Comprehensive Income. 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 the unaudited Condensed Consolidated Statement of Comprehensive Income . 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 the unaudited Condensed Consolidated Statement of Comprehensive Income. The Company did not have any such situations where a derivative ceased to qualify for hedge accounting during 2023, or during the six months ended June 30, 2024. 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 6/30/2024 12/31/2023 6/30/2024 12/31/2023 Derivatives designated as hedges (a) Fuel derivative contracts (gross) Prepaid expenses and other current assets $ 83 $ 86 $ — $ — Fuel derivative contracts (gross) Other assets 139 137 — — Total derivatives designated as hedges $ 222 $ 223 $ — $ — Derivatives not designated as hedges (a) Fuel derivative contracts (gross) Prepaid expenses and other current assets $ 12 $ — $ 14 $ — Total derivatives $ 234 $ 223 $ 14 $ — (a) 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 June 30, December 31, (in millions) location 2024 2023 Cash collateral deposits held from counterparties for fuel contracts - current Offset against Prepaid expenses and other current assets $ 13 $ 15 Cash collateral deposits held from counterparties for fuel contracts - noncurrent Offset against Other assets 17 35 Receivable from third parties for fuel contracts Accounts and other receivables 6 12 All of the Company's derivative instruments 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 its derivative instruments 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. 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 asset 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. The Company had 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) June 30, 2024 December 31, 2023 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 Gross amounts of recognized assets Gross amounts offset in the Balance Sheet Net amounts of assets presented in the Balance Sheet Fuel derivative contracts Prepaid expenses and other current assets $ 95 $ (27) $ 68 $ 86 $ (15) $ 71 Fuel derivative contracts Other assets $ 139 $ (17) $ 122 (a) $ 137 $ (35) $ 102 (a) (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 8. Offsetting of derivative liabilities (in millions) (i) (ii) (iii) = (i) + (ii) (i) (ii) (iii) = (i) + (ii) June 30, 2024 December 31, 2023 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 Gross amounts of recognized liabilities Gross amounts offset in the Balance Sheet Net amounts of liabilities presented in the Balance Sheet Fuel derivative contracts Prepaid expenses and other current assets $ 27 $ (27) $ — $ 15 $ (15) $ — Fuel derivative contracts Other assets $ 17 $ (17) $ — (a) $ 35 $ (35) $ — (a) (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 8. 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 six months ended June 30, 2024 and 2023: Location and amount recognized in income on cash flow hedging relationships Three months ended June 30, 2024 Three months ended June 30, 2023 (in millions) Fuel and oil Other operating expenses Fuel and oil Other operating expenses Total $ 17 $ 2 $ (14) $ 2 (Gain) loss on cash flow hedging relationships Commodity contracts: Amount of (gain) loss reclassified from AOCI into income 17 — (14) — Other: Amount of loss reclassified from AOCI into income — 2 — 2 Location and amount recognized in income on cash flow hedging relationships Six months ended June 30, 2024 Six months ended June 30, 2023 (in millions) Fuel and oil Other operating expenses Fuel and oil Other operating expenses Total $ 39 $ 4 $ (42) $ 3 (Gain) loss on cash flow hedging relationships Commodity contracts: Amount of (gain) loss reclassified from AOCI into income 39 — (42) — Other: Amount of loss reclassified from AOCI into income — 4 — 3 Derivatives designated and qualified in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives, net of tax Three months ended June 30, (in millions) 2024 2023 Fuel derivative contracts $ 23 $ 126 Other $ — (1) Total $ 23 $ 125 Derivatives designated and qualified in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives, net of tax Six months ended June 30, (in millions) 2024 2023 Fuel derivative contracts $ 22 $ 252 Other — — Total $ 22 $ 252 Derivatives not designated as hedges (Gain) loss recognized in income on derivatives Three months ended Location of (gain) loss recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts $ 2 $ 6 Other (gains) losses, net Derivatives not designated as hedges (Gain) loss recognized in income on derivatives Six months ended Location of (gain) loss recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts $ 3 $ 6 Other (gains) losses, net The Company also recorded expense (benefit) associated with premiums paid (received) for fuel derivative contracts that settled/expired during the three and six months ended June 30, 2024 and 2023. Gains and/or losses associated with fuel derivatives that qualify for hedge accounting are ultimately recorded to Fuel and oil expense. Gains and/or losses associated with fuel derivatives that do not qualify for hedge accounting are recorded to Other gains, net. The following tables present the impact of premiums paid (received) for fuel derivative contracts and their location within the unaudited Condensed Consolidated Statement of Comprehensive Income during the period the contract settles: Premium expense (benefit) recognized in income on derivatives Three months ended Location of premium expense (benefit) recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts designated as hedges $ 40 $ 30 Fuel and oil Fuel derivative contracts not designated as hedges (1) — Other (gains) losses, net Premium expense (benefit) recognized in income on derivatives Six months ended Location of premium expense (benefit) recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts designated as hedges $ 79 $ 61 Fuel and oil Fuel derivative contracts not designated as hedges (1) — Other (gains) losses, net 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 unrealized losses from fuel hedges as of June 30, 2024, recorded in AOCI, were approximately $53 million in unrealized losses, net of taxes, which are expected to be realized in the unaudited Condensed Consolidated Statement of Comprehensive Income during the twelve months subsequent to June 30, 2024. Interest Rate Swaps The Company is at times party to certain interest rate swap agreements that are accounted for as cash flow hedges, but had none in place as of June 30, 2024, or as of December 31, 2023. The Company also did not have any interest rate swap agreements designated as fair value hedges, as defined, during the periods presented. During the six months ended June 30, 2023, all of the Company's interest rate swap agreements qualified for the "shortcut" or "critical terms match" methods of accounting for hedges, which dictate that the hedges were assumed to be perfectly effective at origination, and, thus, there was no ineffectiveness to be recorded in the unaudited Condensed Consolidated Statement of Comprehensive Income. All interest rate swap agreements were terminated prior to December 31, 2023. 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 as of 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. As of June 30, 2024, 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's credit rating. The Company also had agreements with counterparties in which cash deposits and letters of credit were required to be posted as collateral whenever the net fair value of derivatives associated with those counterparties exceeds specific thresholds. In certain cases, the Company has the ability to substitute among these different forms of collateral at its discretion. The following table provides the fair values of fuel derivatives, amounts posted as collateral, and applicable collateral posting threshold amounts as of June 30, 2024, at which such postings are triggered: Counterparty (CP) (in millions) A B C D E F G H Total Fair value of fuel derivatives $ 46 $ 28 $ 29 $ 14 $ 40 $ 18 $ 26 $ 19 $ 220 Cash collateral held from CP 30 — — — — — — — 30 Option to substitute LC for cash N/A N/A (a) (a) (a) N/A (a) N/A If credit rating is investment Cash is provided to CP >(100) >(50) >(75) >(125) >(40) >(65) >(100) >(100) Cash is received from CP >0(b) >150(b) >250(b) >125(b) >100(b) >70(b) >100(b) >100(b) If credit rating is non-investment Cash is received from CP (c) (c) (c) (c) (c) (c) (c) (c) (a) The Company has the option to substitute letters of credit for 100 percent of cash collateral requirement. (b) Thresholds may vary based on changes in credit ratings within investment grade. (c) Cash collateral is provided at 100 percent of fair value of fuel derivative contracts.

Comprehensive Income

Comprehensive Income	6 Months Ended
	Jun. 30, 2024
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
COMPREHENSIVE INCOME	COMPREHENSIVE INCOME Comprehensive income includes changes in the fair value of certain financial derivative instruments that qualify for hedge accounting and actuarial gains/losses arising from the Company’s postretirement benefit obligation. The differences between Net income and Comprehensive income for the three and six months ended June 30, 2024 and 2023 were as follows: Three months ended June 30, (in millions) 2024 2023 NET INCOME $ 367 $ 683 Unrealized loss on fuel derivative instruments, net of deferred taxes of ($3) and ($42) (10) (137) Other, net of deferred taxes of $— and $5 2 (2) Total other comprehensive loss $ (8) $ (139) COMPREHENSIVE INCOME $ 359 $ 544 Six months ended June 30, (in millions) 2024 2023 NET INCOME 137 524 Unrealized gain (loss) on fuel derivative instruments, net of deferred taxes of $3 and ($86) 7 (284) Other, net of deferred taxes of $— and $5 4 (2) Total other comprehensive income (loss) 11 (286) COMPREHENSIVE INCOME 148 238 A rollforward of the amounts included in AOCI, net of taxes, is shown below for the three and six months ended June 30, 2024: (in millions) Fuel derivatives Defined benefit plan items Other Deferred tax impact Accumulated other comprehensive income (loss) Balance at March 31, 2024 $ (112) $ 149 $ (13) $ (5) $ 19 Changes in fair value (30) — — 7 (23) Reclassification to earnings 17 — 2 (4) 15 Balance at June 30, 2024 $ (125) $ 149 $ (11) $ (2) $ 11 (in millions) Fuel derivatives Defined benefit plan items Other Deferred tax impact Accumulated other comprehensive income (loss) Balance at December 31, 2023 $ (135) $ 149 $ (15) $ 1 $ — Changes in fair value (29) — — 7 (22) Reclassification to earnings 39 — 4 (10) 33 Balance at June 30, 2024 $ (125) $ 149 $ (11) $ (2) $ 11 The following tables illustrate the significant amounts reclassified out of each component of AOCI for the three and six months ended June 30, 2024: Three months ended June 30, 2024 (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 $ 17 Fuel and oil expense 4 Less: Tax expense $ 13 Net of tax Other $ 2 Other operating expenses — Less: Tax expense $ 2 Net of tax Total reclassifications for the period $ 15 Net of tax Six months ended June 30, 2024 (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 $ 39 Fuel and oil expense 10 Less: Tax expense $ 29 Net of tax Other $ 4 Other operating expenses — Less: Tax expense $ 4 Net of tax Total reclassifications for the period $ 33 Net of tax

Revenue

Revenue	6 Months Ended
	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
REVENUE	REVENUE Passenger Revenues The Company’s contracts with its Customers primarily consist of its tickets sold, which are initially deferred as Air traffic liability. Passenger revenue associated with tickets is recognized when the performance obligation to the Customer is satisfied, which is primarily when travel is provided. Revenue is categorized by revenue source as the Company believes it best depicts the nature, amount, timing, and uncertainty of revenue and cash flow. The following table provides the components of Passenger revenue recognized for the three and six months ended June 30, 2024 and 2023: Three months ended June 30, Six months ended June 30, (in millions) 2024 2023 2024 2023 Passenger non-loyalty $ 5,544 $ 5,183 $ 10,224 $ 9,265 Passenger loyalty - air transportation 895 989 1,694 1,814 Passenger ancillary sold separately 273 237 506 435 Total passenger revenues $ 6,712 $ 6,409 $ 12,424 $ 11,514 As of June 30, 2024, and December 31, 2023, the components of Air traffic liability, including contract liabilities based on tickets sold and unused flight credits available to the Customer, both of which are net of recorded breakage, and loyalty points available for redemption, within the unaudited Condensed Consolidated Balance Sheet were as follows: Balance as of (in millions) June 30, 2024 December 31, 2023 Air traffic liability - passenger travel and ancillary passenger services $ 4,114 $ 3,363 Air traffic liability - loyalty program 4,962 4,916 Total Air traffic liability $ 9,076 $ 8,279 The balance in Air traffic liability - passenger travel and ancillary passenger services also includes flight credits not currently associated with a ticket that can be applied by Customers towards the purchase of future travel. These flight credits are typically created as a result of a prior ticket cancellation or exchange, and are recorded net of associated breakage. Rollforwards of the Company's Air traffic liability - loyalty program for the three and six months ended June 30, 2024 and 2023 were as follows: Three months ended June 30, Six months ended June 30, (in millions) 2024 2023 2024 2023 Air traffic liability - loyalty program - beginning balance $ 4,987 $ 5,190 4,916 $ 5,189 Amounts deferred associated with points awarded 901 903 1,794 1,750 Revenue recognized from points redeemed - Passenger (895) (989) (1,694) (1,814) Revenue recognized from points redeemed - Other (31) (25) (54) (46) Air traffic liability - loyalty program - ending balance $ 4,962 $ 5,079 $ 4,962 $ 5,079 Air traffic liability includes consideration received for ticket and loyalty related performance obligations which have not been satisfied as of a given date. Rollforwards of the amounts included in Air traffic liability as of June 30, 2024 and 2023 were as follows: Six months ended June 30, (in millions) 2024 2023 Air traffic liability - beginning balance $ 8,279 $ 8,250 Current period sales (a) 13,276 12,369 Revenue from amounts included in contract liability opening balances (4,021) (4,170) Revenue from current period sales (8,458) (7,390) Air traffic liability - ending balance $ 9,076 $ 9,059 (a) Current period sales includes passenger travel, ancillary services, flight loyalty, and partner loyalty Under the Company's policy, flight credits never expire. However, as the Company believes that a portion of Customer flight credits issued will not be redeemed, it estimates and records breakage associated with such amounts. The amount of Customer flight credits represents approximately 6 percent and 8 percent of the total Air traffic liability balance as of June 30, 2024, and December 31, 2023, respectively.

Net Income Per Share

Net Income Per Share	6 Months Ended
	Jun. 30, 2024
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). Basic net income per share is calculated by dividing net income by the weighted average of shares outstanding during the period. Diluted net income per share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock. For the three and six months ended June 30, 2024 and 2023, an immaterial number of shares related to the Company's restricted stock units and stock warrants, were excluded from the denominator because inclusion of such shares would be antidilutive. The Company paid $6 million during June 2024 to repurchase and cancel its outstanding stock warrants, previously issued in connection with the Payroll Support Program. Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 NUMERATOR: Net income $ 367 $ 683 $ 137 $ 524 Add: Interest expense 5 5 9 10 Net income attributable to common stockholders $ 372 $ 688 $ 146 $ 534 DENOMINATOR: Weighted-average shares outstanding, basic 599 595 598 595 Dilutive effects of Convertible Notes 43 42 43 42 Dilutive effect of restricted stock units 1 2 2 2 Adjusted weighted-average shares outstanding, diluted 643 639 643 639 NET INCOME PER SHARE: Basic $ 0.61 $ 1.15 $ 0.23 $ 0.88 Diluted $ 0.58 $ 1.08 $ 0.23 $ 0.84

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2024
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 June 30, 2024, 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), fuel derivative contracts, and available-for-sale securities. The majority of the Company’s cash equivalents and short-term investments consist of instruments classified as Level 1. However, the Company has certificates of deposit, commercial paper, and 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. Equity securities primarily consist of investments with readily determinable market values associated with the Company’s excess benefit plan. The Company’s derivative instruments consist of over-the-counter contracts, which are not traded on a public exchange. Fuel derivative instruments currently consist solely of option contracts, whereas interest rate derivatives have historically consisted solely of swap agreements. See Note 3 for further information on the Company’s derivative instruments and hedging activities. 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 a similar 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 deferred compensation plans, which consist of mutual funds that are publicly traded and for which market prices are readily available. These plans are non-qualified deferred compensation plans designed to hold contributions in excess of limits established by the Internal Revenue Code of 1986, as amended. The distribution timing and payment amounts under these plans are made based on the participant’s distribution election and plan balance. Assets related to the funded portions of the deferred compensation plans are held in a rabbi trust, and the Company remains liable to these participants for the unfunded portion of the plans. The Company records changes in the fair value of plan obligations and plan assets, which net to zero, within the Salaries, wages, and benefits line and Other gains, net line, respectively, of the unaudited Condensed Consolidated Statement of Comprehensive Income. The following tables present the Company’s assets and liabilities that are measured at fair value on a recurring basis as of June 30, 2024, and December 31, 2023: Fair value measurements at reporting date using: Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs Description June 30, 2024 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents: Cash equivalents (a) $ 7,796 $ 7,796 $ — $ — Commercial paper 45 — 45 — Certificates of deposit 1 — 1 — Time deposits 300 — 300 — Short-term investments: Treasury bills 1,637 1,637 — — Certificates of deposit 223 — 223 — Fuel derivatives: Option contracts (b) 234 — — 234 Equity Securities 302 302 — — Total assets $ 10,538 $ 9,735 $ 569 $ 234 Liabilities Fuel derivatives: Option contracts (b) $ (14) $ — $ — $ (14) (a) Cash equivalents are primarily composed of money market investments and treasury bills. (b) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net asset. See Note 3. 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, 2023 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents: Cash equivalents (a) $ 9,032 $ 9,032 $ — $ — Commercial paper 135 — 135 — Certificates of deposit 21 — 21 — Time deposits 100 — 100 — Short-term investments: Treasury bills 1,983 1,983 — — Certificates of deposit 203 — 203 — Fuel derivatives: Option contracts (b) 223 — — 223 Equity Securities 280 280 — — Total assets $ 11,977 $ 11,295 $ 459 $ 223 (a) Cash equivalents are primarily composed of money market investments and treasury bills. (b) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as an asset. See Note 3. The Company did not have any material assets or liabilities measured at fair value on a nonrecurring basis during the six months ended June 30, 2024, or the year ended December 31, 2023. 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 six months ended June 30, 2024: Fair value measurements using significant unobservable inputs (Level 3) (in millions) Fuel derivatives Balance as of March 31, 2024 $ 257 Total gains (losses) for the period Included in earnings (2) (a) Included in other comprehensive income (30) Purchases 16 (b) Settlements (21) Balance as of June 30, 2024 $ 220 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 as of June 30, 2024 $ 2 (a) The amount of total losses for the period included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held as of June 30, 2024 $ 23 (a) Included in Other gains, net, within the unaudited Condensed Consolidated Statement of Comprehensive Income . (b) The purchase of fuel derivatives is recorded on a gross basis based on the structure of the derivative instrument and whether a contract with multiple derivatives was purchased as a single instrument or separate instruments. Fair value measurements using significant unobservable inputs (Level 3) (in millions) Fuel derivatives Balance as of December 31, 2023 $ 223 Total gains (losses) for the period Included in earnings (3) (a) Included in other comprehensive income (29) Purchases 67 (b) Settlements (38) Balance as of June 30, 2024 $ 220 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 June 30, 2024 $ 2 (a) The amount of total losses for the period included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2024 $ 35 (a) Included in Other gains, net, within the unaudited Condensed Consolidated Statement of Comprehensive Income . (b) The purchase of fuel derivatives is recorded on a gross basis based on the structure of the derivative instrument and whether a contract with multiple derivatives was purchased as a single instrument or separate instruments. The significant unobservable input used in the fair value measurement of the Company’s derivative option contracts is implied volatility. Holding other inputs constant, an increase (decrease) in implied volatility would have resulted in a higher (lower) fair value measurement, respectively, for the Company’s derivative option contracts. The following table presents a range and weighted average of the unobservable inputs utilized in the fair value measurements of the Company’s fuel derivatives classified as Level 3 as of June 30, 2024: Quantitative information about Level 3 fair value measurements Valuation technique Unobservable input Period (by year) Range Weighted Average (a) Fuel derivatives Option model Implied volatility Third quarter 2024 16-35% 26 % Fourth quarter 2024 22-30% 26 % 2025 21-23% 22 % 2026 21-23% 22 % (a) Implied volatility weighted by the notional amount (barrels of underlying commodity) that will settle in respective period. The carrying amounts and estimated fair values of the Company’s outstanding debt (including current maturities), as well as the applicable fair value hierarchy tier, as of June 30, 2024, are presented in the table below. The fair values of the Company’s publicly held 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. All privately held debt agreements are categorized as Level 3. 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 5.25% Notes due 2025 1,302 1,297 Level 2 1.25% Convertible Notes due 2025 1,611 1,611 Level 2 3.00% Notes due 2026 300 284 Level 2 7.375% Debentures due 2027 109 114 Level 2 3.45% Notes due 2027 300 282 Level 2 5.125% Notes due 2027 1,727 1,718 Level 2 2.625% due 2030 500 434 Level 2 1.000% Payroll Support Program Loan due 2030 (a) 976 955 Level 3 1.000% Payroll Support Program Loan due 2031 (a) 566 532 Level 3 1.000% Payroll Support Program Loan due 2031 (a) 526 488 Level 3 (a) The interest rate will change to Secured Overnight Financing Rate plus two percent on the fifth anniversary of the loans.

Supplemental Financial Informat

Supplemental Financial Information	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
SUPPLEMENTAL FINANCIAL INFORMATION	SUPPLEMENTAL FINANCIAL INFORMATION (in millions) June 30, 2024 December 31, 2023 Trade receivables $ 67 $ 104 Credit card receivables 238 200 Business partners and other suppliers 640 501 Taxes receivable 13 35 Fuel hedging and receivables 6 12 Reinsurance receivable 226 145 Other 156 157 Accounts and other receivables $ 1,346 $ 1,154 (in millions) June 30, 2024 December 31, 2023 Derivative contracts $ 122 $ 102 Intangible assets, net 300 296 Equity securities 302 280 Prepaid maintenance 263 258 Other 58 28 Other assets $ 1,045 $ 964 (in millions) June 30, 2024 December 31, 2023 Accounts payable trade $ 330 $ 265 Salaries, withholdings and payroll taxes 479 400 Ticket taxes and fees 426 302 Aircraft maintenance payable 140 140 Fuel payable 119 161 Dividends payable 108 107 Accrued third party services 181 269 Other payable 245 218 Accounts payable $ 2,028 $ 1,862 (in millions) June 30, 2024 December 31, 2023 Voluntary Separation Program $ 64 $ 65 Profitsharing and savings plans 63 141 Vacation pay 578 516 Health 183 163 Workers compensation 141 133 Property and income taxes 70 63 Interest 34 34 Bonus and incentive pay (a) 186 2,022 Reinsurance payable 282 190 Other 269 279 Accrued liabilities $ 1,870 $ 3,606 (in millions) June 30, 2024 December 31, 2023 Voluntary Separation Program $ 20 $ 61 Postretirement obligation 277 269 Other deferred compensation 379 358 Other 250 293 Other noncurrent liabilities $ 926 $ 981 (a) Primarily consists of contract labor ratification bonuses and/or accruals. Also includes non-contract incentive pay. Approximately $1.9 billion was paid in the six months ended June 30, 2024 to Pilots, Flight Attendants, and Ramp, Operations, Provisioning, and Cargo Agents as bonuses upon the ratification of the labor contract agreements with the Southwest Airlines Pilots Association ("SWAPA"), Transport Workers of America Union Local 556 ("TWU 556"), and the Transport Workers Union Local 555 ("TWU 555"), respectively. For further information on derivative instruments, see Note 3. Other Operating Expenses Other operating expenses consist of aircraft rentals, distribution costs, advertising expenses, personnel expenses, professional fees, certain technology-related costs, and other operating costs, none of which individually exceeded 10 percent of Total operating expenses.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Commitments The Company's contractual order book with The Boeing Company ("Boeing") for 737-7 ("-7") and 737-8 ("-8") aircraft, which extends to 2031, was designed to support the Company's growth and fleet modernization plans, while also providing significant flexibility and optionality to manage its fleet gauge and size, including opportunities to accelerate fleet modernization efforts if growth opportunities do not materialize. The Company received five -8 aircraft deliveries from Boeing in second quarter 2024 and retired six -700 aircraft and one 737-800 ("-800") aircraft. Boeing continues to experience delays in fulfilling its commitments with regards to delivery of MAX aircraft to the Company, as a result of manufacturing challenges, as well as delays in achieving FAA certification of one of its new aircraft types, the -7, for which Southwest expects to be the launch customer. During first quarter 2024, as a result of Boeing's delivery delays, the Company conservatively re-planned its capacity and delivery expectations for the remainder of this year and for 2025. While the Company has not further adjusted capacity expectations this quarter, it will continue to closely monitor the ongoing aircraft delivery delays with Boeing and adjust expectations, conservatively, as needed. During April 2024, the Company shifted one 2025 -8 option into 2026. As of June 30, 2024, the Company had the following firm orders and options for future periods: The Boeing Company -7 Firm Orders -8 Firm Orders -7 or -8 Options Total 2024 27 58 — 85 (c) 2025 40 19 14 73 2026 59 — 27 86 2027 19 46 25 90 2028 15 50 25 90 2029 38 34 18 90 2030 45 — 45 90 2031 45 — 45 90 288 (a) 207 (b) 199 694 (a) The delivery timing for the -7 is dependent on the Federal Aviation Administration ("FAA") issuing required certifications and approvals to Boeing and the Company. The FAA will ultimately determine the timing of the -7 certification and entry into service, and the Company therefore offers no assurances that current estimations and timelines are correct. (b) The Company has flexibility to designate firm orders or options as -7s or -8s, upon written advance notification as stated in the contract. (c) Includes 10 -8 deliveries received year-to-date through June 30, 2024. Given the Company's continued discussions with Boeing and expected aircraft delivery delays, the Company continues to plan for approximately 20 -8 aircraft deliveries in 2024. Based on the Company's current agreement with Boeing, capital commitments associated with firm orders as of June 30, 2024, were: $1.8 billion remaining in 2024, $1.7 billion in 2025, $1.8 billion in 2026, $2.6 billion in 2027, $2.9 billion in 2028, $2.5 billion in 2029, and $2.8 billion thereafter. Subsequent to June 30, 2024 and through July 25, 2024, the Company exercised two -7 options for delivery in 2025, and converted two 2025 -7 firm orders to -8 firm orders, resulting in the Company's 2025 capital commitments increasing to $1.8 billion. Contingencies The Company is from time to time subject to various legal proceedings and claims arising in the ordinary course of business and records a liability for such claims when it is probable that a loss will be incurred and the amount is reasonably estimable. The Company is a defendant in class action litigation asserting it has not provided paid short-term military leave to certain employees, in violation of the federal Uniformed Services Employment and Reemployment Rights Act (“USERRA”). The United States District Court for the Northern District of California previously issued an order to effectively stay the action, pending an appeal from an order by the United States District Court for the Eastern District of Washington granting summary judgment in favor of an airline in a separate case involving substantially the same claims at issue in this action. On February 1, 2023, the Ninth Circuit reversed the district court’s grant of summary judgment and remanded the separate airline case to the District Court. The Ninth Circuit’s decision may adversely affect the Company’s defenses in the USERRA proceeding and may give rise to additional litigation in this or other areas. On March 22, 2024, the parties in the Company's case submitted a proposed case schedule through trial. The Court subsequently set a trial date of July 21, 2025. The Company is currently not able to estimate a range of possible loss with regards to the litigation to which it is a defendant.

Financing Activities

Financing Activities	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
FINANCING ACTIVITIES	FINANCING ACTIVITIES On May 1, 2020, the Company completed the public offering of $2.3 billion aggregate principal amount of Convertible Senior Notes (the "Convertible Notes"). The Convertible Notes bear interest at a rate of 1.25% and will mature on May 1, 2025. Interest on the notes is payable semi-annually in arrears. Holders may convert their Convertible Notes at their option at any time prior to the close of business on the business day immediately preceding February 1, 2025, in the event certain conditions are met, as stated in the offering documents. The Convertible Notes did not meet the criteria to be converted as of June 30, 2024, but are classified within Current maturities of long-term debt in the accompanying unaudited Condensed Consolidated Balance Sheet due to their maturity on May 1, 2025. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of the Company’s common stock, or a combination of cash and shares of common stock, at the Company’s election. The Company intends to settle conversions by paying cash up to the principal amount of the Convertible Notes, with any excess conversion value settled in cash or shares of common stock. The initial conversion rate was 25.9909 shares of common stock per $1,000 principal amount of Convertible Notes (equivalent to an initial conversion price of approximately $38.48 per share of common stock). However, based on the Company's most recent cash dividends declared in May 2024, the bond conversion rate changed, and was 27.0296 as of June 30, 2024. The Company repurchased $689 million in principal of its Convertible Notes during the years ended December 31, 2021 and 2022, and the net carrying amount and principal amount of the Convertible Notes was $1.6 billion as of June 30, 2024, and December 31, 2023. There were no Convertible Note conversions exercised or settled or partial extinguishments of debt during the six months ended June 30, 2024 and 2023. The Company recognized interest expense associated with the Convertible Notes as follows: Three months ended June 30, Six months ended June 30, (in millions) 2024 2023 2024 2023 Non-cash amortization of debt issuance costs $ 3 $ 3 $ 5 $ 5 Contractual coupon interest 5 5 10 10 Total interest expense $ 8 $ 8 $ 15 $ 15 The unamortized debt issuance costs are being recognized as non-cash interest expense based on the 5-year term of the notes, through May 1, 2025, less amounts that were or will be required to be accelerated immediately upon conversion or repurchases. The Company had no changes to contingencies with regards to the Convertible Notes during the six months ended June 30, 2024. The effective interest rate associated with the Convertible Notes was approximately 1.9 percent for the three and six months ended June 30, 2024. In second quarter 2024, the Company repurchased and terminated the Company's outstanding stock warrants that were previously issued in connection with the Payroll Support Program. The total value of the repurchase was approximately $6 million. The Company has access to $1.0 billion under its amended and restated revolving credit facility (the "Amended Credit Agreement"), which expires in August 2028. For the six months ended June 30, 2024 and 2023, there were no amounts outstanding under the Amended Credit Agreement. On December 5, 2022, the Company signed an aircraft sale agreement with AerCap Ireland Limited (“AerCap”) to purchase 39 -700 aircraft, all of which were already in the Company's fleet under finance lease terms. As each aircraft was purchased, the Company relieved its related lease liability but continued to recognize the cost of the aircraft within Property and equipment in the unaudited Condensed Consolidated Balance Sheet. As of March 31, 2023, the Company had completed the purchase of all 39 aircraft, including the 31 aircraft purchased in 2022. The Company paid the lessor $88 million as part of this transaction for the remaining eight aircraft in first quarter 2023, of which $50 million was recorded as the elimination of the Company’s remaining finance lease obligation for the aircraft, and which was also reflected within Payments of long-term debt and finance lease obligations in the accompanying unaudited Condensed Consolidated Statement of Cash Flows. The remaining $38 million was the net purchase price of the aircraft and is included as part of the Company’s Capital expenditures for the six months ended June 30, 2023. As of June 30, 2024, the Company has 22 finance leased aircraft remaining. There was no gain or loss recorded as a result of these transactions.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2024
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS On July 2, 2024, the Company's Board of Directors (the “Board”) adopted a shareholder rights plan and declared a dividend of one right (a “Right”) in respect of each of the Company’s issued and outstanding shares of common stock, par value $1.00 per share (“Common Stock”). The dividend is payable to the shareholders of record at the close of business on July 15, 2024. Each Right initially entitles the registered holder, subject to the terms of the Rights Agreement (as defined below), to purchase from the Company one ten-thousandth (a “Unit”) of a share of Common Stock, at a price equal to the quotient of $170.00 divided by ten thousand for each Unit of a share of Common Stock, subject to certain adjustments (as adjusted from time to time, the “Exercise Price”). The terms of the Rights are set forth in the Rights Agreement, dated as of July 2, 2024 (as it may be amended from time to time, the “Rights Agreement”), by and between the Company and Equiniti Trust Company, LLC, as rights agent (or any successor rights agent, the “Rights Agent”). The adoption of the Rights Agreement is intended to deter the acquisition of actual, de facto, or negative control of the Company by any person or group without appropriately compensating its Shareholders for that control. In general terms, the Rights Agreement imposes significant dilution upon any person or group (other than the Company or certain related persons) that is or becomes the beneficial owner of 12.5 percent (the “Triggering Percentage”) or more of the Company’s outstanding Common Stock without the prior approval of the Board. A person or group that becomes the beneficial owner of the Triggering Percentage or more is called an “Acquiring Person.” Any Rights held by an Acquiring Person will be null and void and may not be exercised. Shareholders that beneficially own the Triggering Percentage or more of the Company’s outstanding Common Stock on the date the plan is adopted, are not considered Acquiring Persons; however, such Shareholders generally may not acquire, or obtain the right to acquire, beneficial ownership of one or more additional shares of the Company’s outstanding Common Stock. The term “beneficial ownership” is defined in the Rights Agreement and includes, among other things, certain securities that may be exercised or converted into shares of Common Stock and certain derivative arrangements. The Rights will expire prior to the earliest of (i) the close of business on July 1, 2025; (ii) the time at which the Rights are redeemed pursuant to the Rights Agreement; (iii) the time at which the Rights are exchanged pursuant to the Rights Agreement; and (iv) upon the occurrence of certain transactions. This description of the Rights Agreement herein does not purport to be complete and is qualified in its entirety by reference to Exhibit 4.1 to the Company’s Current Report on Form 8-K, filed with the SEC on July 3, 2024.

New Accounting Pronouncements (

New Accounting Pronouncements (Policies)	6 Months Ended
	Jun. 30, 2024
Accounting Standards Update and Change in Accounting Principle [Abstract]
Basis of Presentation	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 June 30, 2024 and 2023 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 performed 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 and changes in consumer behavior, unemployment levels, corporate travel budgets, global pandemics, extreme or severe weather and natural disasters, fears of terrorism or war, governmental actions, 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, and the periodic volatility of commodities used by the Company for hedging jet fuel, 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 fuel hedging program. Operating results for the three and six months ended June 30, 2024, are not necessarily indicative of the results that may be expected for future quarters or for the year ended December 31, 2024. For further information, refer to the Consolidated Financial Statements and footnotes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2023.
New Accounting Pronouncements	On December 14, 2023, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update ("ASU") 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This standard increases transparency and decision usefulness of income tax disclosures for investors by requiring information to better assess how an entity's operations and related tax risks and tax planning and operational opportunities affect its tax rate and prospects for future cash flows. This standard requires entities to provide enhanced disclosures related to the income tax rate reconciliation and income taxes paid. This standard is effective for all entities that are subject to Topic 740, Income Taxes for annual periods beginning after December 15, 2024, but early adoption is permitted. The Company is evaluating this new standard but does not expect it to have a significant impact on its financial statement presentation or results. On November 27, 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This standard improves reportable segment disclosures by adding and enhancing interim disclosure requirements, clarifying circumstances in which entities can disclose multiple segment measures of profit or loss, providing new segment disclosure requirements for entities with a single reportable segment, and adding other disclosure requirements. This standard is effective for all entities that are subject to Topic 280, Segment Reporting for annual periods beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, but early adoption is permitted. The Company is evaluating this new standard but does not expect it to have a significant impact on its financial statement presentation or results.
Derivatives	The Company has used financial derivative instruments for both short-term and long-term timeframes, and historically has used 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. The Company does not purchase or hold any financial derivative instruments for trading or speculative purposes. For the purpose of evaluating its net cash spend for jet fuel and for forecasting its future estimated jet fuel expense, 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 the Company defines as prices significantly higher than historical average levels), 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. Upon proper qualification, the Company accounts for its fuel derivative instruments as cash flow hedges. Qualification is re-evaluated quarterly, and all periodic changes in fair value of the derivatives designated as hedges are recorded in Accumulated other comprehensive income ("AOCI") until the underlying jet fuel is consumed. See Note 4. When the Company has sold derivative positions in order to effectively "close" or offset a derivative already held as part of its fuel hedging portfolio, any subsequent changes in fair value of those positions are marked to market through the unaudited Condensed Consolidated Statement of Comprehensive Income. 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 the unaudited Condensed Consolidated Statement of Comprehensive Income . The Company is at times party to certain interest rate swap agreements that are accounted for as cash flow hedges, but had none in place as of June 30, 2024, or as of December 31, 2023. The Company also did not have any interest rate swap agreements designated as fair value hedges, as defined, during the periods presented. During the six months ended June 30, 2023, all of the Company's interest rate swap agreements qualified for the "shortcut" or "critical terms match" methods of accounting for hedges, which dictate that the hedges were assumed to be perfectly effective at origination, and, thus, there was no ineffectiveness to be recorded in the unaudited Condensed Consolidated Statement of Comprehensive Income. All interest rate swap agreements were terminated prior to December 31, 2023.
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 June 30, 2024, 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), fuel derivative contracts, and available-for-sale securities. The majority of the Company’s cash equivalents and short-term investments consist of instruments classified as Level 1. However, the Company has certificates of deposit, commercial paper, and 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. Equity securities primarily consist of investments with readily determinable market values associated with the Company’s excess benefit plan. The Company’s derivative instruments consist of over-the-counter contracts, which are not traded on a public exchange. Fuel derivative instruments currently consist solely of option contracts, whereas interest rate derivatives have historically consisted solely of swap agreements. See Note 3 for further information on the Company’s derivative instruments and hedging activities. 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 a similar 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 deferred compensation plans, which consist of mutual funds that are publicly traded and for which market prices are readily available. These plans are non-qualified deferred compensation plans designed to hold contributions in excess of limits established by the Internal Revenue Code of 1986, as amended. The distribution timing and payment amounts under these plans are made based on the participant’s distribution election and plan balance. Assets related to the funded portions of the deferred compensation plans are held in a rabbi trust, and the Company remains liable to these participants for the unfunded portion of the plans. The Company records changes in the fair value of plan obligations and plan assets, which net to zero, within the Salaries, wages, and benefits line and Other gains, net line, respectively, of the unaudited Condensed Consolidated Statement of Comprehensive Income.
Revenue Recognition	The Company recognized revenue related to the marketing, advertising, and other travel-related benefits of the revenue associated with various loyalty partner agreements including, but not limited to, its co-branded credit card agreement with Chase Bank USA, N.A, within Other operating revenues.

Basis of Presentation (Tables)

Basis of Presentation (Tables)	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Schedule of Change in Accounting Estimate	These accelerated retirement dates, and the corresponding impact to depreciation expense, are considered a change in estimate and resulted in the following impact to Depreciation and amortization expense for the three and six months ended June 30, 2024: Three months ended Six months ended (in millions, except per share amounts) June 30, 2024 June 30, 2024 Depreciation and amortization expense $ 10 $ 10 Net income * $ (6) $ (6) Net income per basic share $ (0.01) $ (0.01) Net income per diluted share $ (0.01) $ (0.01) * net of profitsharing benefit and income taxes

Financial Derivative Instrume_2

Financial Derivative Instruments (Tables)	6 Months Ended
	Jun. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Volume of Fuel Hedging	The following table provides information about the Company’s volume of fuel hedged on an economic basis: Maximum fuel hedged as of June 30, 2024 Derivative underlying commodity type as of Period (by year) (gallons in millions) (a) June 30, 2024 Remainder of 2024 633 West Texas Intermediate ("WTI") crude oil, Brent crude oil, and Heating oil 2025 1,033 Brent crude oil 2026 832 Brent crude oil (a) Due to the types of derivatives utilized by the Company and different price levels of those contracts, these volumes represent the maximum economic hedge in place and may vary significantly as market prices fluctuate and if the Company's published flight schedule or capacity plans change.
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 6/30/2024 12/31/2023 6/30/2024 12/31/2023 Derivatives designated as hedges (a) Fuel derivative contracts (gross) Prepaid expenses and other current assets $ 83 $ 86 $ — $ — Fuel derivative contracts (gross) Other assets 139 137 — — Total derivatives designated as hedges $ 222 $ 223 $ — $ — Derivatives not designated as hedges (a) Fuel derivative contracts (gross) Prepaid expenses and other current assets $ 12 $ — $ 14 $ — Total derivatives $ 234 $ 223 $ 14 $ — (a) 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.
Offsetting Assets	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 June 30, December 31, (in millions) location 2024 2023 Cash collateral deposits held from counterparties for fuel contracts - current Offset against Prepaid expenses and other current assets $ 13 $ 15 Cash collateral deposits held from counterparties for fuel contracts - noncurrent Offset against Other assets 17 35 Receivable from third parties for fuel contracts Accounts and other receivables 6 12 The Company had 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) June 30, 2024 December 31, 2023 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 Gross amounts of recognized assets Gross amounts offset in the Balance Sheet Net amounts of assets presented in the Balance Sheet Fuel derivative contracts Prepaid expenses and other current assets $ 95 $ (27) $ 68 $ 86 $ (15) $ 71 Fuel derivative contracts Other assets $ 139 $ (17) $ 122 (a) $ 137 $ (35) $ 102 (a) (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 8.
Offsetting Liabilities	Offsetting of derivative liabilities (in millions) (i) (ii) (iii) = (i) + (ii) (i) (ii) (iii) = (i) + (ii) June 30, 2024 December 31, 2023 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 Gross amounts of recognized liabilities Gross amounts offset in the Balance Sheet Net amounts of liabilities presented in the Balance Sheet Fuel derivative contracts Prepaid expenses and other current assets $ 27 $ (27) $ — $ 15 $ (15) $ — Fuel derivative contracts Other assets $ 17 $ (17) $ — (a) $ 35 $ (35) $ — (a) (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 8.
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss)	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 six months ended June 30, 2024 and 2023: Location and amount recognized in income on cash flow hedging relationships Three months ended June 30, 2024 Three months ended June 30, 2023 (in millions) Fuel and oil Other operating expenses Fuel and oil Other operating expenses Total $ 17 $ 2 $ (14) $ 2 (Gain) loss on cash flow hedging relationships Commodity contracts: Amount of (gain) loss reclassified from AOCI into income 17 — (14) — Other: Amount of loss reclassified from AOCI into income — 2 — 2 Location and amount recognized in income on cash flow hedging relationships Six months ended June 30, 2024 Six months ended June 30, 2023 (in millions) Fuel and oil Other operating expenses Fuel and oil Other operating expenses Total $ 39 $ 4 $ (42) $ 3 (Gain) loss on cash flow hedging relationships Commodity contracts: Amount of (gain) loss reclassified from AOCI into income 39 — (42) — Other: Amount of loss reclassified from AOCI into income — 4 — 3 Derivatives designated and qualified in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives, net of tax Three months ended June 30, (in millions) 2024 2023 Fuel derivative contracts $ 23 $ 126 Other $ — (1) Total $ 23 $ 125 Derivatives designated and qualified in cash flow hedging relationships (Gain) loss recognized in AOCI on derivatives, net of tax Six months ended June 30, (in millions) 2024 2023 Fuel derivative contracts $ 22 $ 252 Other — — Total $ 22 $ 252
Derivative Instruments, Gain (Loss)	Derivatives not designated as hedges (Gain) loss recognized in income on derivatives Three months ended Location of (gain) loss recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts $ 2 $ 6 Other (gains) losses, net Derivatives not designated as hedges (Gain) loss recognized in income on derivatives Six months ended Location of (gain) loss recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts $ 3 $ 6 Other (gains) losses, net
Premiums Paid for Fuel Derivative Contracts	The following tables present the impact of premiums paid (received) for fuel derivative contracts and their location within the unaudited Condensed Consolidated Statement of Comprehensive Income during the period the contract settles: Premium expense (benefit) recognized in income on derivatives Three months ended Location of premium expense (benefit) recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts designated as hedges $ 40 $ 30 Fuel and oil Fuel derivative contracts not designated as hedges (1) — Other (gains) losses, net Premium expense (benefit) recognized in income on derivatives Six months ended Location of premium expense (benefit) recognized in income on derivatives June 30, (in millions) 2024 2023 Fuel derivative contracts designated as hedges $ 79 $ 61 Fuel and oil Fuel derivative contracts not designated as hedges (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 June 30, 2024, at which such postings are triggered: Counterparty (CP) (in millions) A B C D E F G H Total Fair value of fuel derivatives $ 46 $ 28 $ 29 $ 14 $ 40 $ 18 $ 26 $ 19 $ 220 Cash collateral held from CP 30 — — — — — — — 30 Option to substitute LC for cash N/A N/A (a) (a) (a) N/A (a) N/A If credit rating is investment Cash is provided to CP >(100) >(50) >(75) >(125) >(40) >(65) >(100) >(100) Cash is received from CP >0(b) >150(b) >250(b) >125(b) >100(b) >70(b) >100(b) >100(b) If credit rating is non-investment Cash is received from CP (c) (c) (c) (c) (c) (c) (c) (c) (a) The Company has the option to substitute letters of credit for 100 percent of cash collateral requirement. (b) Thresholds may vary based on changes in credit ratings within investment grade. (c) Cash collateral is provided at 100 percent of fair value of fuel derivative contracts.

Comprehensive Income (Tables)

Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2024
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Components of Comprehensive Income (Loss)	The differences between Net income and Comprehensive income for the three and six months ended June 30, 2024 and 2023 were as follows: Three months ended June 30, (in millions) 2024 2023 NET INCOME $ 367 $ 683 Unrealized loss on fuel derivative instruments, net of deferred taxes of ($3) and ($42) (10) (137) Other, net of deferred taxes of $— and $5 2 (2) Total other comprehensive loss $ (8) $ (139) COMPREHENSIVE INCOME $ 359 $ 544 Six months ended June 30, (in millions) 2024 2023 NET INCOME 137 524 Unrealized gain (loss) on fuel derivative instruments, net of deferred taxes of $3 and ($86) 7 (284) Other, net of deferred taxes of $— and $5 4 (2) Total other comprehensive income (loss) 11 (286) COMPREHENSIVE INCOME 148 238
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 six months ended June 30, 2024: (in millions) Fuel derivatives Defined benefit plan items Other Deferred tax impact Accumulated other comprehensive income (loss) Balance at March 31, 2024 $ (112) $ 149 $ (13) $ (5) $ 19 Changes in fair value (30) — — 7 (23) Reclassification to earnings 17 — 2 (4) 15 Balance at June 30, 2024 $ (125) $ 149 $ (11) $ (2) $ 11 (in millions) Fuel derivatives Defined benefit plan items Other Deferred tax impact Accumulated other comprehensive income (loss) Balance at December 31, 2023 $ (135) $ 149 $ (15) $ 1 $ — Changes in fair value (29) — — 7 (22) Reclassification to earnings 39 — 4 (10) 33 Balance at June 30, 2024 $ (125) $ 149 $ (11) $ (2) $ 11
Reclassification out of Accumulated Other Comprehensive Income (Loss)	The following tables illustrate the significant amounts reclassified out of each component of AOCI for the three and six months ended June 30, 2024: Three months ended June 30, 2024 (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 $ 17 Fuel and oil expense 4 Less: Tax expense $ 13 Net of tax Other $ 2 Other operating expenses — Less: Tax expense $ 2 Net of tax Total reclassifications for the period $ 15 Net of tax Six months ended June 30, 2024 (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 $ 39 Fuel and oil expense 10 Less: Tax expense $ 29 Net of tax Other $ 4 Other operating expenses — Less: Tax expense $ 4 Net of tax Total reclassifications for the period $ 33 Net of tax

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
Disaggregation of Passenger Revenue	The following table provides the components of Passenger revenue recognized for the three and six months ended June 30, 2024 and 2023: Three months ended June 30, Six months ended June 30, (in millions) 2024 2023 2024 2023 Passenger non-loyalty $ 5,544 $ 5,183 $ 10,224 $ 9,265 Passenger loyalty - air transportation 895 989 1,694 1,814 Passenger ancillary sold separately 273 237 506 435 Total passenger revenues $ 6,712 $ 6,409 $ 12,424 $ 11,514
Rollforward of Air Traffic Liability	As of June 30, 2024, and December 31, 2023, the components of Air traffic liability, including contract liabilities based on tickets sold and unused flight credits available to the Customer, both of which are net of recorded breakage, and loyalty points available for redemption, within the unaudited Condensed Consolidated Balance Sheet were as follows: Balance as of (in millions) June 30, 2024 December 31, 2023 Air traffic liability - passenger travel and ancillary passenger services $ 4,114 $ 3,363 Air traffic liability - loyalty program 4,962 4,916 Total Air traffic liability $ 9,076 $ 8,279 Three months ended June 30, Six months ended June 30, (in millions) 2024 2023 2024 2023 Air traffic liability - loyalty program - beginning balance $ 4,987 $ 5,190 4,916 $ 5,189 Amounts deferred associated with points awarded 901 903 1,794 1,750 Revenue recognized from points redeemed - Passenger (895) (989) (1,694) (1,814) Revenue recognized from points redeemed - Other (31) (25) (54) (46) Air traffic liability - loyalty program - ending balance $ 4,962 $ 5,079 $ 4,962 $ 5,079 Six months ended June 30, (in millions) 2024 2023 Air traffic liability - beginning balance $ 8,279 $ 8,250 Current period sales (a) 13,276 12,369 Revenue from amounts included in contract liability opening balances (4,021) (4,170) Revenue from current period sales (8,458) (7,390) Air traffic liability - ending balance $ 9,076 $ 9,059 (a) Current period sales includes passenger travel, ancillary services, flight loyalty, and partner loyalty

Net Income Per Share (Tables)

Net Income Per Share (Tables)	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Schedule of Earnings per Share, Basic and Diluted	Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 NUMERATOR: Net income $ 367 $ 683 $ 137 $ 524 Add: Interest expense 5 5 9 10 Net income attributable to common stockholders $ 372 $ 688 $ 146 $ 534 DENOMINATOR: Weighted-average shares outstanding, basic 599 595 598 595 Dilutive effects of Convertible Notes 43 42 43 42 Dilutive effect of restricted stock units 1 2 2 2 Adjusted weighted-average shares outstanding, diluted 643 639 643 639 NET INCOME PER SHARE: Basic $ 0.61 $ 1.15 $ 0.23 $ 0.88 Diluted $ 0.58 $ 1.08 $ 0.23 $ 0.84

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2024
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 as of June 30, 2024, and December 31, 2023: Fair value measurements at reporting date using: Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs Description June 30, 2024 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents: Cash equivalents (a) $ 7,796 $ 7,796 $ — $ — Commercial paper 45 — 45 — Certificates of deposit 1 — 1 — Time deposits 300 — 300 — Short-term investments: Treasury bills 1,637 1,637 — — Certificates of deposit 223 — 223 — Fuel derivatives: Option contracts (b) 234 — — 234 Equity Securities 302 302 — — Total assets $ 10,538 $ 9,735 $ 569 $ 234 Liabilities Fuel derivatives: Option contracts (b) $ (14) $ — $ — $ (14) (a) Cash equivalents are primarily composed of money market investments and treasury bills. (b) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net asset. See Note 3. 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, 2023 (Level 1) (Level 2) (Level 3) Assets (in millions) Cash equivalents: Cash equivalents (a) $ 9,032 $ 9,032 $ — $ — Commercial paper 135 — 135 — Certificates of deposit 21 — 21 — Time deposits 100 — 100 — Short-term investments: Treasury bills 1,983 1,983 — — Certificates of deposit 203 — 203 — Fuel derivatives: Option contracts (b) 223 — — 223 Equity Securities 280 280 — — Total assets $ 11,977 $ 11,295 $ 459 $ 223 (a) Cash equivalents are primarily composed of money market investments and treasury bills. (b) In the unaudited Condensed Consolidated Balance Sheet amounts are presented as an asset. See Note 3.
Fair Value, Assets 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 six months ended June 30, 2024: Fair value measurements using significant unobservable inputs (Level 3) (in millions) Fuel derivatives Balance as of March 31, 2024 $ 257 Total gains (losses) for the period Included in earnings (2) (a) Included in other comprehensive income (30) Purchases 16 (b) Settlements (21) Balance as of June 30, 2024 $ 220 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 as of June 30, 2024 $ 2 (a) The amount of total losses for the period included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held as of June 30, 2024 $ 23 (a) Included in Other gains, net, within the unaudited Condensed Consolidated Statement of Comprehensive Income . (b) The purchase of fuel derivatives is recorded on a gross basis based on the structure of the derivative instrument and whether a contract with multiple derivatives was purchased as a single instrument or separate instruments. Fair value measurements using significant unobservable inputs (Level 3) (in millions) Fuel derivatives Balance as of December 31, 2023 $ 223 Total gains (losses) for the period Included in earnings (3) (a) Included in other comprehensive income (29) Purchases 67 (b) Settlements (38) Balance as of June 30, 2024 $ 220 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 June 30, 2024 $ 2 (a) The amount of total losses for the period included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2024 $ 35 (a) Included in Other gains, net, within the unaudited Condensed Consolidated Statement of Comprehensive Income . (b) The purchase of fuel derivatives is recorded on a gross basis based on the structure of the derivative instrument and whether a contract with multiple derivatives was purchased as a single instrument or separate instruments.
Fair Value Valuation Techniques	The following table presents a range and weighted average of the unobservable inputs utilized in the fair value measurements of the Company’s fuel derivatives classified as Level 3 as of June 30, 2024: Quantitative information about Level 3 fair value measurements Valuation technique Unobservable input Period (by year) Range Weighted Average (a) Fuel derivatives Option model Implied volatility Third quarter 2024 16-35% 26 % Fourth quarter 2024 22-30% 26 % 2025 21-23% 22 % 2026 21-23% 22 % (a) Implied volatility weighted by the notional amount (barrels of underlying commodity) that will settle in respective period.
Fair value, by Balance Sheet Grouping	The carrying amounts and estimated fair values of the Company’s outstanding debt (including current maturities), as well as the applicable fair value hierarchy tier, as of June 30, 2024, are presented in the table below. The fair values of the Company’s publicly held 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. All privately held debt agreements are categorized as Level 3. 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 5.25% Notes due 2025 1,302 1,297 Level 2 1.25% Convertible Notes due 2025 1,611 1,611 Level 2 3.00% Notes due 2026 300 284 Level 2 7.375% Debentures due 2027 109 114 Level 2 3.45% Notes due 2027 300 282 Level 2 5.125% Notes due 2027 1,727 1,718 Level 2 2.625% due 2030 500 434 Level 2 1.000% Payroll Support Program Loan due 2030 (a) 976 955 Level 3 1.000% Payroll Support Program Loan due 2031 (a) 566 532 Level 3 1.000% Payroll Support Program Loan due 2031 (a) 526 488 Level 3 (a) The interest rate will change to Secured Overnight Financing Rate plus two percent on the fifth anniversary of the loans.

Supplemental Financial Inform_2

Supplemental Financial Information (Tables)	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts and Other Receivables	(in millions) June 30, 2024 December 31, 2023 Trade receivables $ 67 $ 104 Credit card receivables 238 200 Business partners and other suppliers 640 501 Taxes receivable 13 35 Fuel hedging and receivables 6 12 Reinsurance receivable 226 145 Other 156 157 Accounts and other receivables $ 1,346 $ 1,154
Other Assets	(in millions) June 30, 2024 December 31, 2023 Derivative contracts $ 122 $ 102 Intangible assets, net 300 296 Equity securities 302 280 Prepaid maintenance 263 258 Other 58 28 Other assets $ 1,045 $ 964
Schedule of Accounts Payable	(in millions) June 30, 2024 December 31, 2023 Accounts payable trade $ 330 $ 265 Salaries, withholdings and payroll taxes 479 400 Ticket taxes and fees 426 302 Aircraft maintenance payable 140 140 Fuel payable 119 161 Dividends payable 108 107 Accrued third party services 181 269 Other payable 245 218 Accounts payable $ 2,028 $ 1,862
Accrued Liabilities	(in millions) June 30, 2024 December 31, 2023 Voluntary Separation Program $ 64 $ 65 Profitsharing and savings plans 63 141 Vacation pay 578 516 Health 183 163 Workers compensation 141 133 Property and income taxes 70 63 Interest 34 34 Bonus and incentive pay (a) 186 2,022 Reinsurance payable 282 190 Other 269 279 Accrued liabilities $ 1,870 $ 3,606
Other Noncurrent Liabilities	(in millions) June 30, 2024 December 31, 2023 Voluntary Separation Program $ 20 $ 61 Postretirement obligation 277 269 Other deferred compensation 379 358 Other 250 293 Other noncurrent liabilities $ 926 $ 981 (a) Primarily consists of contract labor ratification bonuses and/or accruals. Also includes non-contract incentive pay. Approximately $1.9 billion was paid in the six months ended June 30, 2024 to Pilots, Flight Attendants, and Ramp, Operations, Provisioning, and Cargo Agents as bonuses upon the ratification of the labor contract agreements with the Southwest Airlines Pilots Association ("SWAPA"), Transport Workers of America Union Local 556 ("TWU 556"), and the Transport Workers Union Local 555 ("TWU 555"), respectively.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Contractual Purchase Commitments	As of June 30, 2024, the Company had the following firm orders and options for future periods: The Boeing Company -7 Firm Orders -8 Firm Orders -7 or -8 Options Total 2024 27 58 — 85 (c) 2025 40 19 14 73 2026 59 — 27 86 2027 19 46 25 90 2028 15 50 25 90 2029 38 34 18 90 2030 45 — 45 90 2031 45 — 45 90 288 (a) 207 (b) 199 694 (a) The delivery timing for the -7 is dependent on the Federal Aviation Administration ("FAA") issuing required certifications and approvals to Boeing and the Company. The FAA will ultimately determine the timing of the -7 certification and entry into service, and the Company therefore offers no assurances that current estimations and timelines are correct. (b) The Company has flexibility to designate firm orders or options as -7s or -8s, upon written advance notification as stated in the contract. (c) Includes 10 -8 deliveries received year-to-date through June 30, 2024. Given the Company's continued discussions with Boeing and expected aircraft delivery delays, the Company continues to plan for approximately 20 -8 aircraft deliveries in 2024.

Financing Activities (Tables)

Financing Activities (Tables)	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Interest Income and Interest Expense Disclosure	The Company recognized interest expense associated with the Convertible Notes as follows: Three months ended June 30, Six months ended June 30, (in millions) 2024 2023 2024 2023 Non-cash amortization of debt issuance costs $ 3 $ 3 $ 5 $ 5 Contractual coupon interest 5 5 10 10 Total interest expense $ 8 $ 8 $ 15 $ 15

Basis of Presentation - Narrati

Basis of Presentation - Narrative (Details) $ in Millions		3 Months Ended
	Dec. 31, 2022 flight	Mar. 31, 2023 USD ($)
Accounting Policies [Abstract]
Number of cancelled flights (more than) | flight	16,700
Customer reimbursements other expenses | $		$ 55

Basis of Presentation - Change

Basis of Presentation - Change in Accounting Estimate (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Change in Accounting Estimate [Line Items]
Depreciation and amortization expense	$ 404	$ 367	$ 812	$ 731
Net income	$ 367	$ 683	$ 137	$ 524
Net income per share, basic (in USD per share)	$ 0.61	$ 1.15	$ 0.23	$ 0.88
Net income per share, diluted (in USD per share)	$ 0.58	$ 1.08	$ 0.23	$ 0.84
Service Life
Change in Accounting Estimate [Line Items]
Depreciation and amortization expense	$ 10		$ 10
Net income	$ (6)		$ (6)
Net income per share, basic (in USD per share)	$ (0.01)		$ (0.01)
Net income per share, diluted (in USD per share)	$ (0.01)		$ (0.01)

Financial Derivative Instrume_3

Financial Derivative Instruments - Fuel Hedging (Details) gal in Millions	6 Months Ended
	Jun. 30, 2024 gal
Remainder of 2024
Volume of Fuel Hedging
Fuel Hedged (in gallons)	633
2025
Volume of Fuel Hedging
Fuel Hedged (in gallons)	1,033
2026
Volume of Fuel Hedging
Fuel Hedged (in gallons)	832

Financial Derivative Instrume_4

Financial Derivative Instruments - Fair Values by Balance Sheet Location (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Gross amounts of recognized assets	$ 234	$ 223
Gross amounts of recognized liabilities	14	0
Fuel derivative contracts | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Gross amounts of recognized assets	95	86
Gross amounts of recognized liabilities	27	15
Fuel derivative contracts | Other assets
Derivatives, Fair Value [Line Items]
Gross amounts of recognized assets	139	137
Gross amounts of recognized liabilities	17	35
Cash collateral deposits held from counterparties for fuel contracts	17	35
Fuel derivative contracts | Other Current Assets
Derivatives, Fair Value [Line Items]
Cash collateral deposits held from counterparties for fuel contracts	13	15
Fuel derivative contracts | Accounts and other receivables
Derivatives, Fair Value [Line Items]
Receivable from third parties for fuel contracts	6	12
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Gross amounts of recognized assets	222	223
Gross amounts of recognized liabilities	0	0
Designated as Hedging Instrument | Fuel derivative contracts | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Gross amounts of recognized assets	83	86
Gross amounts of recognized liabilities	0	0
Designated as Hedging Instrument | Fuel derivative contracts | Other assets
Derivatives, Fair Value [Line Items]
Gross amounts of recognized assets	139	137
Gross amounts of recognized liabilities	0	0
Not Designated as Hedging Instrument | Fuel derivative contracts | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Gross amounts of recognized assets	12	0
Gross amounts of recognized liabilities	$ 14	$ 0

Financial Derivative Instrume_5

Financial Derivative Instruments - Narrative (Details) $ in Millions	Jun. 30, 2024 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Net unrealized losses, net of taxes	$ 53

Financial Derivative Instrume_6

Financial Derivative Instruments - Offsetting of Derivative Assets (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Offsetting Assets [Line Items]
Gross amounts of recognized assets	$ 234	$ 223
Fuel derivative contracts | Prepaid expenses and other current assets
Offsetting Assets [Line Items]
Gross amounts of recognized assets	95	86
Gross amounts offset in the Balance Sheet	(27)	(15)
Net amounts of assets presented in the Balance Sheet	68	71
Fuel derivative contracts | Other assets
Offsetting Assets [Line Items]
Gross amounts of recognized assets	139	137
Gross amounts offset in the Balance Sheet	(17)	(35)
Net amounts of assets presented in the Balance Sheet	$ 122	$ 102

Financial Derivative Instrume_7

Financial Derivative Instruments - Offsetting Derivative Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	$ 14	$ 0
Fuel derivative contracts | Prepaid expenses and other current assets
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	27	15
Gross amounts offset in the Balance Sheet	(27)	(15)
Net amounts of liabilities presented in the Balance Sheet	0	0
Fuel derivative contracts | Other assets
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	17	35
Gross amounts offset in the Balance Sheet	(17)	(35)
Net amounts of liabilities presented in the Balance Sheet	$ 0	$ 0

Financial Derivative Instrume_8

Financial Derivative Instruments - Location and Amount Recognized in Income by Hedging Relationship (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Cash Flow Hedging
Derivative [Line Items]
Amount of (gain) loss reclassified from AOCI into income	$ 23	$ 125	$ 22	$ 252
Cash Flow Hedging | Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) loss reclassified from AOCI into income	23	126	22	252
Cash Flow Hedging | Other
Derivative [Line Items]
Amount of (gain) loss reclassified from AOCI into income	0	(1)	0	0
Fuel and oil
Derivative [Line Items]
Total	17	(14)	39	(42)
Fuel and oil | Cash Flow Hedging | Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) loss reclassified from AOCI into income	17	(14)	39	(42)
Fuel and oil | Cash Flow Hedging | Other
Derivative [Line Items]
Amount of (gain) loss reclassified from AOCI into income	0	0	0	0
Other operating expenses
Derivative [Line Items]
Total	2	2	4	3
Other operating expenses | Cash Flow Hedging | Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) loss reclassified from AOCI into income	0	0	0	0
Other operating expenses | Cash Flow Hedging | Other
Derivative [Line Items]
Amount of (gain) loss reclassified from AOCI into income	$ (2)	$ (2)	$ (4)	$ (3)

Financial Derivative Instrume_9

Financial Derivative Instruments - (Gain) Loss by Hedging Relationship (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Fuel derivative contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) loss recognized in AOCI on derivatives, net of tax	$ 23	$ 125	$ 22	$ 252
Cash Flow Hedging | Fuel derivative contracts
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) loss recognized in AOCI on derivatives, net of tax	23	126	22	252
Cash Flow Hedging | Other
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) loss recognized in AOCI on derivatives, net of tax	0	(1)	0	0
Not Designated as Hedging Instrument | Fuel derivative contracts
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) loss recognized in income on derivatives	$ 2	$ 6	$ 3	$ 6

Financial Derivative Instrum_10

Financial Derivative Instruments - Premiums for Fuel Derivative Contracts (Details) - Fuel derivative contracts - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Designated as Hedging Instrument | Fuel and oil
Derivative [Line Items]
Premium expense (benefit) recognized in income on derivatives	$ 40	$ 30	$ 79	$ 61
Not Designated as Hedging Instrument | Other (gains)/losses, net
Derivative [Line Items]
Premium expense (benefit) recognized in income on derivatives	$ (1)	$ 0	$ (1)	$ 0

Financial Derivative Instrum_11

Financial Derivative Instruments - Fair Values of Fuel Derivatives Amounts Posted as Collateral (Details) $ in Millions	Jun. 30, 2024 USD ($)
If credit rating is investment grade, fair value of fuel derivative level at which:
Letter of credit substitution percentage	100%
Cash collateral percentage	100%
Fuel derivative contracts
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	$ 220
Cash collateral held from CP	30
Fuel derivative contracts | Counterparty A
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	46
Cash collateral held from CP	30
Fuel derivative contracts | Counterparty A | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(100)
Cash is received from CP	0
Fuel derivative contracts | Counterparty B
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	28
Cash collateral held from CP	0
Fuel derivative contracts | Counterparty B | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(50)
Cash is received from CP	150
Fuel derivative contracts | Counterparty C
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	29
Cash collateral held from CP	0
Fuel derivative contracts | Counterparty C | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(75)
Cash is received from CP	250
Fuel derivative contracts | Counterparty D
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	14
Cash collateral held from CP	0
Fuel derivative contracts | Counterparty D | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(125)
Cash is received from CP	125
Fuel derivative contracts | Counterparty E
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	40
Cash collateral held from CP	0
Fuel derivative contracts | Counterparty E | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(40)
Cash is received from CP	100
Fuel derivative contracts | Counterparty F
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	18
Cash collateral held from CP	0
Fuel derivative contracts | Counterparty F | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(65)
Cash is received from CP	70
Fuel derivative contracts | Counterparty G
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	26
Cash collateral held from CP	0
Fuel derivative contracts | Counterparty G | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(100)
Cash is received from CP	100
Fuel derivative contracts | Counterparty H
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items]
Fair value of fuel derivatives	19
Cash collateral held from CP	0
Fuel derivative contracts | Counterparty H | Minimum
If credit rating is investment grade, fair value of fuel derivative level at which:
Cash is provided to CP	(100)
Cash is received from CP	$ 100

Comprehensive Income - Differen

Comprehensive Income - Differences between Net Income (Loss) and Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Condensed Statement of Income Captions [Line Items]
NET INCOME	$ 367		$ 683		$ 137	$ 524
Other, net of deferred taxes	2		(2)		4	(2)
Total other comprehensive loss	(8)		(139)		11	(286)
COMPREHENSIVE INCOME	359	$ (212)	544	$ (306)	148	238
Other deferred taxes	0		5		0	5
Fuel derivative contracts
Condensed Statement of Income Captions [Line Items]
Unrealized gain (loss) on derivative instruments, net of deferred taxes	(10)		(137)		7	(284)
Derivative deferred taxes	$ (3)		$ (42)		$ 3	$ (86)

Comprehensive Income - Schedule

Comprehensive Income - Schedule of AOCI Components (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2024
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ 10,196	$ 10,515
Changes in fair value	(23)	(22)
Reclassification to earnings	15	33
Balance at end of period	10,465	10,465
Accumulated other comprehensive income (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	19	0
Balance at end of period	11	11
Fuel derivatives | Fuel derivative contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(112)	(135)
Changes in fair value	(30)	(29)
Reclassification to earnings	17	39
Balance at end of period	(125)	(125)
Defined benefit plan items
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	149	149
Changes in fair value	0	0
Reclassification to earnings	0	0
Balance at end of period	149	149
Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(13)	(15)
Changes in fair value	0	0
Reclassification to earnings	2	4
Balance at end of period	(11)	(11)
Deferred tax impact
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(5)	1
Changes in fair value	7	7
Reclassification to earnings	(4)	(10)
Balance at end of period	$ (2)	$ (2)

Comprehensive Income - Reclassi

Comprehensive Income - Reclassifications (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Fuel and oil expense	$ 1,599	$ 1,403	$ 3,130	$ 2,950
Tax expense	111	203	44	158
Other operating expenses	1,093	956	2,110	1,909
Net of tax	367	$ 683	137	$ 524
Amounts reclassified from AOCI
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Net of tax	15		33
Fuel derivative contracts | Fuel derivatives | Amounts reclassified from AOCI
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Fuel and oil expense	17		39
Tax expense	4		10
Net of tax	13		29
Other | Fuel derivatives | Amounts reclassified from AOCI
Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Tax expense	0		0
Other operating expenses	2		4
Net of tax	$ 2		$ 4

Revenue - Passenger Revenue Bre

Revenue - Passenger Revenue Breakout (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Disaggregation of Revenue [Line Items]
Operating revenue	$ 7,354	$ 7,037	$ 13,683	$ 12,743
Passenger
Disaggregation of Revenue [Line Items]
Operating revenue	6,712	6,409	12,424	11,514
Passenger non-loyalty
Disaggregation of Revenue [Line Items]
Operating revenue	5,544	5,183	10,224	9,265
Passenger loyalty - air transportation
Disaggregation of Revenue [Line Items]
Operating revenue	895	989	1,694	1,814
Passenger ancillary sold separately
Disaggregation of Revenue [Line Items]
Operating revenue	$ 273	$ 237	$ 506	$ 435

Revenue - Air Traffic Liability

Revenue - Air Traffic Liability Breakout (Details) - USD ($) $ in Millions	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Air traffic liability - passenger travel and ancillary passenger services	$ 4,114		$ 3,363
Air traffic liability - loyalty program	4,962	$ 4,987	4,916	$ 5,079	$ 5,190	$ 5,189
Total Air traffic liability	$ 9,076		$ 8,279	$ 9,059		$ 8,250

Revenue - Air Traffic Liabili_2

Revenue - Air Traffic Liability - Loyalty Program Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Change in Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 4,987	$ 5,190	$ 4,916	$ 5,189
Amounts deferred associated with points awarded	901	903	1,794	1,750
Ending balance	4,962	5,079	4,962	5,079
Passenger Customer
Change in Contract With Customer, Liability [Roll Forward]
Revenue recognized from points redeemed	(895)	(989)	(1,694)	(1,814)
Other
Change in Contract With Customer, Liability [Roll Forward]
Revenue recognized from points redeemed	$ (31)	$ (25)	$ (54)	$ (46)

Revenue - Air Traffic Liabili_3

Revenue - Air Traffic Liability Rollforward (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Change in Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 8,279	$ 8,250
Current period sales	13,276	12,369
Revenue from amounts included in contract liability opening balances	(4,021)	(4,170)
Revenue from current period sales	(8,458)	(7,390)
Ending balance	$ 9,076	$ 9,059

Revenue - Narrative (Details)

Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Residual travel funds (as a percent)	6%		6%		8%
Total operating revenues	$ 7,354	$ 7,037	$ 13,683	$ 12,743
Chase Bank USA Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total operating revenues	$ 556	$ 540	$ 1,100	$ 1,100

Net Income Per Share (Details)

Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings Per Share [Abstract]
Payments for repurchased common stock warrants	$ 6	$ 6	$ 0	$ 6	$ 0
NUMERATOR:
Net income		367	683	137	524
Add: Interest expense		5	5	9	10
Net income attributable to common stockholders		$ 372	$ 688	$ 146	$ 534
DENOMINATOR:
Weighted-average shares outstanding, basic (in shares)		599	595	598	595
Dilutive effects of Convertible Notes (in shares)		43	42	43	42
Dilutive effect of restricted stock units (in shares)		1	2	2	2
Adjusted weighted-average shares outstanding, diluted (in shares)		643	639	643	639
NET INCOME PER SHARE:
Basic (in USD per share)		$ 0.61	$ 1.15	$ 0.23	$ 0.88
Diluted (in USD per share)		$ 0.58	$ 1.08	$ 0.23	$ 0.84

Fair Value Measurements - Measu

Fair Value Measurements - Measured on Recurring Basis (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Fuel derivatives:
Option contracts	$ 234	$ 223
Fair Value, Measurements, Recurring
Assets
Treasury bills	1,637	1,983
Fuel derivatives:
Equity Securities	302	280
Total assets	10,538	11,977
Fair Value, Measurements, Recurring | Option contracts
Fuel derivatives:
Option contracts	234	223
Fair Value, Measurements, Recurring | Option contracts
Liabilities
Option contracts	(14)
Fair Value, Measurements, Recurring | Certificates of deposit
Assets
Certificates of deposit	223	203
Fair Value, Measurements, Recurring | Cash equivalents
Assets
Cash equivalents	7,796	9,032
Fair Value, Measurements, Recurring | Commercial paper
Assets
Cash equivalents	45	135
Fair Value, Measurements, Recurring | Certificates of deposit
Assets
Cash equivalents	1	21
Fair Value, Measurements, Recurring | Time deposits
Assets
Cash equivalents	300	100
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1)
Assets
Treasury bills	1,637	1,983
Fuel derivatives:
Equity Securities	302	280
Total assets	9,735	11,295
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) | Option contracts
Fuel derivatives:
Option contracts	0	0
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) | Option contracts
Liabilities
Option contracts	0
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) | Certificates of deposit
Assets
Certificates of deposit	0	0
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) | Cash equivalents
Assets
Cash equivalents	7,796	9,032
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) | Commercial paper
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) | Certificates of deposit
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) | Time deposits
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2)
Assets
Treasury bills	0	0
Fuel derivatives:
Equity Securities	0	0
Total assets	569	459
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) | Option contracts
Fuel derivatives:
Option contracts	0	0
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) | Option contracts
Liabilities
Option contracts	0
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) | Certificates of deposit
Assets
Certificates of deposit	223	203
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) | Cash equivalents
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) | Commercial paper
Assets
Cash equivalents	45	135
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) | Certificates of deposit
Assets
Cash equivalents	1	21
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) | Time deposits
Assets
Cash equivalents	300	100
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3)
Assets
Treasury bills	0	0
Fuel derivatives:
Equity Securities	0	0
Total assets	234	223
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) | Option contracts
Fuel derivatives:
Option contracts	234	223
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) | Option contracts
Liabilities
Option contracts	(14)
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) | Certificates of deposit
Assets
Certificates of deposit	0	0
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) | Cash equivalents
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) | Commercial paper
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) | Certificates of deposit
Assets
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) | Time deposits
Assets
Cash equivalents	$ 0	$ 0

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Assets and Liabilities Measured on Recurring Basis with Unobservable Inputs (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2024
Fuel derivative contracts
Total gains (losses) for the period
Purchases	$ 16	$ 67
Fuel derivative contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	257	223
Total gains (losses) for the period
Included in earnings	(2)	(3)
Included in other comprehensive income	(30)	(29)
Settlements	(21)	(38)
Ending Balance	220	220
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 as of June 30, 2024	2	2
The amount of total losses for the period included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held as of June 30, 2024	$ 23	$ 35

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative Information about Level 3 Fair Value (Details) - Significant unobservable inputs (Level 3) - Measurement Input, Option Volatility	Jun. 30, 2024
Third quarter 2024 | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.16
Third quarter 2024 | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.35
Third quarter 2024 | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.26
Fourth quarter 2024 | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.22
Fourth quarter 2024 | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.30
Fourth quarter 2024 | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.26
2025 | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.21
2025 | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.23
2025 | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.22
2026 | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.21
2026 | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.23
2026 | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Implied volatility	0.22

Fair Value Measurements - Carry

Fair Value Measurements - Carrying and Estimated Fair Value of Debt (Details) - USD ($) $ in Millions	Apr. 20, 2025	Jun. 30, 2024	May 01, 2020
Unsecured Debt | 5.25% Notes due 2025
Debt Instrument [Line Items]
Carrying value		$ 1,302
Unsecured Debt | 3.00% Notes due 2026
Debt Instrument [Line Items]
Carrying value		300
Unsecured Debt | 7.375% Debentures due 2027
Debt Instrument [Line Items]
Carrying value		109
Unsecured Debt | 3.45% Notes due 2027
Debt Instrument [Line Items]
Carrying value		300
Unsecured Debt | 5.125% Notes due 2027
Debt Instrument [Line Items]
Carrying value		1,727
Unsecured Debt | 2.625% due 2030
Debt Instrument [Line Items]
Carrying value		500
Unsecured Debt | 1.000% Payroll Support Program Loan due 2030
Debt Instrument [Line Items]
Carrying value		976
Unsecured Debt | 1.000% Payroll Support Program Loan due 2030 | Forecast
Debt Instrument [Line Items]
Variable rate (as a percent)	2%
Unsecured Debt | 1.000% Payroll Support Program Loan due 2031
Debt Instrument [Line Items]
Carrying value		566
Unsecured Debt | 1.000% Payroll Support Program Loan due 2031 | Forecast
Debt Instrument [Line Items]
Variable rate (as a percent)	2%
Unsecured Debt | 1.000% Payroll Support Program Loan Due 2031
Debt Instrument [Line Items]
Carrying value		526
Unsecured Debt | 1.000% Payroll Support Program Loan Due 2031 | Forecast
Debt Instrument [Line Items]
Variable rate (as a percent)	2%
Convertible Debt | 1.25% Convertible Notes due 2025
Debt Instrument [Line Items]
Carrying value		$ 1,611
Level 2 | Unsecured Debt | 5.25% Notes due 2025
Debt Instrument [Line Items]
Stated interest rate		5.25%
Notes payable, Estimated Fair Value		$ 1,297
Level 2 | Unsecured Debt | 3.00% Notes due 2026
Debt Instrument [Line Items]
Stated interest rate		3%
Notes payable, Estimated Fair Value		$ 284
Level 2 | Unsecured Debt | 7.375% Debentures due 2027
Debt Instrument [Line Items]
Stated interest rate		7.375%
Loans payable, Estimated Fair Value		$ 114
Level 2 | Unsecured Debt | 3.45% Notes due 2027
Debt Instrument [Line Items]
Stated interest rate		3.45%
Notes payable, Estimated Fair Value		$ 282
Level 2 | Unsecured Debt | 5.125% Notes due 2027
Debt Instrument [Line Items]
Stated interest rate		5.125%
Notes payable, Estimated Fair Value		$ 1,718
Level 2 | Unsecured Debt | 2.625% due 2030
Debt Instrument [Line Items]
Stated interest rate		2.625%
Notes payable, Estimated Fair Value		$ 434
Level 2 | Convertible Debt | 1.25% Convertible Notes due 2025
Debt Instrument [Line Items]
Stated interest rate		1.25%	1.25%
Notes payable, Estimated Fair Value		$ 1,611
Level 3 | Unsecured Debt | 1.000% Payroll Support Program Loan due 2030
Debt Instrument [Line Items]
Stated interest rate		1%
Notes payable, Estimated Fair Value		$ 955
Level 3 | Unsecured Debt | 1.000% Payroll Support Program Loan due 2031
Debt Instrument [Line Items]
Stated interest rate		1%
Notes payable, Estimated Fair Value		$ 532
Level 3 | Unsecured Debt | 1.000% Payroll Support Program Loan Due 2031
Debt Instrument [Line Items]
Stated interest rate		1%
Notes payable, Estimated Fair Value		$ 488

Supplemental Financial Inform_3

Supplemental Financial Information - Accounts and Other Receivables (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Trade receivables	$ 67	$ 104
Credit card receivables	238	200
Business partners and other suppliers	640	501
Taxes receivable	13	35
Fuel hedging and receivables	6	12
Reinsurance receivable	226	145
Other	156	157
Accounts and other receivables	$ 1,346	$ 1,154

Supplemental Financial Inform_4

Supplemental Financial Information - Other Assets (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Derivative contracts	$ 122	$ 102
Intangible assets, net	300	296
Equity securities	302	280
Prepaid maintenance	263	258
Other	58	28
Other assets	$ 1,045	$ 964

Supplemental Financial Inform_5

Supplemental Financial Information - Accounts Payable (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts payable trade	$ 330	$ 265
Salaries, withholdings and payroll taxes	479	400
Ticket taxes and fees	426	302
Aircraft maintenance payable	140	140
Fuel payable	119	161
Dividends payable	108	107
Accrued third party services	181	269
Other payable	245	218
Accounts payable	$ 2,028	$ 1,862

Supplemental Financial Inform_6

Supplemental Financial Information - Accrued Liabilities (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Accrued Liabilities, Current [Abstract]
Voluntary Separation Program	$ 64	$ 65
Profitsharing and savings plans	63	141
Vacation pay	578	516
Health	183	163
Workers compensation	141	133
Property and income taxes	70	63
Interest	34	34
Bonus and incentive pay	186	2,022
Reinsurance payable	282	190
Other	269	279
Accrued liabilities	1,870	$ 3,606
Payment of bonus and incentive pay as a ratification of the labor contract agreement	$ 1,900

Supplemental Financial Inform_7

Supplemental Financial Information - Other Non-Current Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Voluntary Separation Program	$ 20	$ 61
Postretirement obligation	277	269
Other deferred compensation	379	358
Other	250	293
Other noncurrent liabilities	$ 926	$ 981

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) $ in Billions	1 Months Ended		3 Months Ended	6 Months Ended
	Jul. 25, 2024 USD ($) aircraft	Apr. 30, 2024 aircraft	Jun. 30, 2024 USD ($) aircraft	Jun. 30, 2024 USD ($) aircraft
B737-8
Long-term Purchase Commitment [Line Items]
Number of aircraft deliveries | aircraft			5	10
Number of aircraft options shifted | aircraft		1
B737-8 | Subsequent Event
Long-term Purchase Commitment [Line Items]
Number of aircraft orders converted | aircraft	2
B-737-700
Long-term Purchase Commitment [Line Items]
Number of aircraft retirements | aircraft			6
B-737-800
Long-term Purchase Commitment [Line Items]
Number of aircraft retirements | aircraft			1
B737-7 | Subsequent Event
Long-term Purchase Commitment [Line Items]
Number of aircraft options exercised | aircraft	2
Aircraft
Long-term Purchase Commitment [Line Items]
Capital commitments remainder of 2024			$ 1.8	$ 1.8
Capital commitments in 2025			1.7	1.7
Capital commitments in 2026			1.8	1.8
Capital commitments in 2027			2.6	2.6
Capital commitments in 2028			2.9	2.9
Capital commitments in 2029			2.5	2.5
Capital commitments thereafter			$ 2.8	$ 2.8
Aircraft | Subsequent Event
Long-term Purchase Commitment [Line Items]
Capital commitments in 2025	$ 1.8

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Firm Orders (Details)	3 Months Ended	6 Months Ended
	Jun. 30, 2024 aircraft	Jun. 30, 2024 aircraft
Firm Orders
2024	85	85
2025	73	73
2026	86	86
2027	90	90
2028	90	90
2029	90	90
2030	90	90
2031	90	90
Total number of aircrafts ordered	694	694
-7 Firm Orders
Firm Orders
2024	27	27
2025	40	40
2026	59	59
2027	19	19
2028	15	15
2029	38	38
2030	45	45
2031	45	45
Total number of aircrafts ordered	288	288
-8 Firm Orders
Firm Orders
2024	58	58
2025	19	19
2026	0	0
2027	46	46
2028	50	50
2029	34	34
2030	0	0
2031	0	0
Total number of aircrafts ordered	207	207
Number of aircraft deliveries	5	10
Number of aircrafts to be delivered	20	20
-7 or -8 Options
Firm Orders
2024	0	0
2025	14	14
2026	27	27
2027	25	25
2028	25	25
2029	18	18
2030	45	45
2031	45	45
Total number of aircrafts ordered	199	199

Financing Activities - Narrativ

Financing Activities - Narrative (Details)			1 Months Ended	3 Months Ended			6 Months Ended
	Jun. 30, 2024 USD ($) aircraft	May 01, 2020 USD ($) $ / shares	Jun. 30, 2024 USD ($) aircraft	Jun. 30, 2024 USD ($) aircraft	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($) aircraft	Jun. 30, 2024 USD ($) aircraft	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) aircraft	Dec. 05, 2022 aircraft	Dec. 31, 2021 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Value of warrant repurchase and termination			$ 6,000,000	$ 6,000,000	$ 0		$ 6,000,000	$ 0
Capital expenditures				494,000,000	925,000,000		1,077,000,000	1,971,000,000
Payments of long-term debt and finance lease obligations				$ 8,000,000	8,000,000		$ 16,000,000	67,000,000
Boeing 737-700 | Air Transportation Equipment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of aircrafts to be purchased | aircraft											39
Number of aircrafts purchased | aircraft						8				31
Capital expenditures						$ 88,000,000
Payments of long-term debt and finance lease obligations						$ 50,000,000
Total lease obligations					38,000,000			38,000,000
Number of leased aircrafts | aircraft	22		22	22			22
Gain (loss) on sale of leased aircraft							$ 0
Convertible Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Principal amount	$ 1,600,000,000	$ 2,300,000,000	$ 1,600,000,000	$ 1,600,000,000			$ 1,600,000,000		$ 1,600,000,000
Conversion ratio	0.0270296	0.0259909
Initial conversion price (in USD per share) | $ / shares		$ 38.48
Principal amount of debt repurchased										$ 689,000,000		$ 689,000,000
Term (in years)							5 years
Convertible Debt | 1.25% Convertible Notes due 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amounts outstanding	$ 1,611,000,000		$ 1,611,000,000	$ 1,611,000,000			$ 1,611,000,000
Convertible Debt | 1.25% Convertible Notes due 2025 | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate	1.25%	1.25%	1.25%	1.25%			1.25%
Line of Credit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Borrowing capacity	$ 1,000,000,000		$ 1,000,000,000	$ 1,000,000,000			$ 1,000,000,000
Amounts outstanding	$ 0		$ 0	$ 0	$ 0		$ 0	$ 0
Notes Due 2027
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Effective interest rate	1.90%		1.90%	1.90%			1.90%

Financing Activities - Interest

Financing Activities - Interest Expense (Details) - Convertible Debt - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Debt Instrument [Line Items]
Non-cash amortization of debt issuance costs	$ 3	$ 3	$ 5	$ 5
Contractual coupon interest	5	5	10	10
Total interest expense	$ 8	$ 8	$ 15	$ 15

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event	Jul. 02, 2024 right $ / shares shares
Subsequent Event [Line Items]
Dividend declared per common share (in rights per share) | right	1
Common stock par value (in dollars per share)	$ 1
Conversion ratio of rights into shares (in shares) | shares	0.0001
Exercise price of rights (in dollars per share)	$ 0.017
Minimum dilution percentage before becoming beneficial owner (as a percent)	0.125