Offsetting Liabilities Offsetting Liabilities [Line Items] Freight Cargo and Freight [Member] Short-term and Noncurrent Investments Investment, Policy [Policy Text Block] Employee Retirement Plans Postemployment Benefit Plans, Policy [Policy Text Block] Fuel derivative contracts Commodity Contract [Member] Expected Return on Plan Assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Schedule of Estimated Future Benefit Payments Schedule of Expected Benefit Payments [Table Text Block] 2030 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Five Cash collateral deposits held from counterparties for fuel contracts - current Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset Award Timing Predetermined Award Timing Predetermined [Flag] Indefinite-lived Intangible Assets [Axis] Indefinite-Lived Intangible Assets [Axis] Entity File Number Entity File Number Capital in excess of par value Additional Paid-in Capital [Member] Tabular List, Table Tabular List [Table Text Block] Defined benefit plan, plan assets, target allocation (as percent) Defined Benefit Plan, Plan Assets, Target Allocation, Percentage SUPPLEMENTAL FINANCIAL INFORMATION Additional Financial Information Disclosure [Text Block] New Accounting Pronouncements and Accounting Changes New Accounting Pronouncements, Policy [Policy Text Block] Purchases of short-term investments Payments to Acquire Short-Term Investments Type of Aircraft [Domain] Aircraft [Domain] Secured Overnight Financing Rate (SOFR) Secured Overnight Financing Rate (SOFR) [Member] Schedule of Fair Value of Debt Fair Value, by Balance Sheet Grouping [Table Text Block] Schedule of Change in Accounting Estimate Schedule of Change in Accounting Estimate [Table Text Block] Assets Leases, Assets [Abstract] Leases, Assets Research and development tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Stock Compensation Plan - Board of Directors Share-Based Payment Arrangement [Member] Adjustment to Compensation: Adjustment to Compensation [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Percentage of total shares acquired on initial delivery Accelerated Share Repurchase, Initial Delivery, Percentage Of Shares Accelerated Share Repurchase, Initial Delivery, Percentage Of Shares Los Angeles World Airports Los Angeles World Airports [Member] Los Angeles World Airports REVENUE Revenue from Contract with Customer [Text Block] Number of aircraft orders converted Long-Term Purchase Commitment, Quantity Converted Long-Term Purchase Commitment, Quantity Converted Total number of shares purchased (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Total current Current Income Tax Expense (Benefit) Other Other Assets, Miscellaneous, Noncurrent Employee stock purchase plan [Abstract] Employee Stock Purchase Plan [Abstract] -- None. No documentation exists for this element. -- Adjustment to Compensation, Amount Adjustment to Compensation Amount Full-time employees unionized (as a percent) Concentration Risk, Percentage Market Based Cash Balance Plan Pension Plan [Member] Other assets Increase (Decrease) in Other Operating Assets Current Lease Liabilities, Current [Abstract] Lease Liabilities, Current Employee Stock Option Share-Based Payment Arrangement, Option [Member] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] Percent Effective Income Tax Rate Reconciliation, Percent [Abstract] Ultimate health care cost trend rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Deferred taxes on unrealized gain (loss) on derivatives, tax effect Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax Total stockholders' equity Balance at beginning of period Balance at end of period Equity, Attributable to Parent Insider Trading Policies and Procedures [Line Items] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Initial price paid per share for shares repurchased (in USD per share) Accelerated Share Repurchases, Initial Price Paid Per Share Concentration Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Payments of long-term debt and operating lease obligations Repayments Of Other Long-Term Debt And Operating Lease Obligations Repayments Of Other Long-Term Debt And Operating Lease Obligations LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] State and Local Jurisdiction State and Local Jurisdiction [Member] Cover [Abstract] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Maximum Maximum [Member] Property and equipment, at cost: Property, Plant and Equipment, Net [Abstract] Net book value of assets pledged as collateral for the Company's secured borrowings, primarily aircraft and engines Debt Instrument, Collateral Amount Gain on sale-leaseback transactions Gain on sale-leaseback transactions Sale and Leaseback Transaction, Gain (Loss), Net Software Capitalization Internal Use Software, Policy [Policy Text Block] Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Debt Instrument [Line Items] Debt Instrument [Line Items] Schedule of share-based compensation arrangements by share-based payment award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Fuel and oil Fuel Costs Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Retirement Benefits [Abstract] Retirement Benefits [Abstract] Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Other assets Other Assets [Member] Salaries, withholdings and payroll taxes Accrued Salaries, Current Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] INCOME BEFORE INCOME TAXES Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Proceeds from sale of property, plant, and equipment Proceeds from Sale of Property, Plant, and Equipment Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Proceeds from issuance of long-term debt Proceeds from Issuance of Debt Included in earnings Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Schedule of Cash Flow, Supplemental Disclosures Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Unrealized gain (loss) on fuel derivative instruments, net of deferred taxes of $13, ($14), and ($103) Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Boeing 737-700 Boeing 737-700 [Member] Boeing 737-700 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 year-end Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), OCI Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Unrecognized prior service cost Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax Number of aircrafts de-recognized Sale Leaseback Transaction, Number Of Aircrafts Derecognized Sale Leaseback Transaction, Number Of Aircrafts Derecognized Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Restructuring reserve Restructuring Reserve Offsetting Liabilities [Table] Offsetting Liabilities [Table] TEXAS TEXAS Current operating lease liabilities Operating Less current obligations Operating Lease, Liability, Current Nontaxable or nondeductible items Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent [Abstract] Interest on finance lease liabilities Finance Lease, Interest Expense Credit card receivables Credit Card Receivables Software Software and Software Development Costs [Member] Document Fiscal Period Focus Document Fiscal Period Focus Accounts and Other Receivables Receivable [Policy Text Block] Derivatives, Fair Value Derivatives, Fair Value [Line Items] First Quarter 2026 ASR Program First Quarter 2026 ASR Program [Member] First Quarter 2026 ASR Program Award Timing Method Award Timing Method [Text Block] Schedule of share-based compensation arrangements by share-based payment award, award type and plan name [Axis] Award Type [Axis] Air traffic liability - noncurrent Contract with Customer, Liability, Noncurrent Hedging Relationship [Domain] Hedging Relationship [Domain] Residual travel funds (as a percent) Residual Travel Funds Residual Travel Funds Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Share-based Employee Compensation Share-Based Payment Arrangement [Policy Text Block] Trading Symbol Trading Symbol 2029 Lessee, Operating Lease, Liability, to be Paid, Year Four Changes in valuation allowances Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Grant Year 2025 Grant Year 2025 [Member] Grant Year 2025 Entity Address, City or Town Entity Address, City or Town Expense recognized in income on derivatives Derivative, Premium (Benefit) Expense Derivative, Premium (Benefit) Expense Finance leases (as a percent) Finance Lease, Weighted Average Discount Rate, Percent Total deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Income Statement Location [Domain] Statement of Income Location, Balance [Domain] Restricted stock units Restricted Stock Units (RSUs) [Member] Change in Accounting Estimate [Table] Change in Accounting Estimate [Table] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Accounts and other receivables Accounts And Other Receivables [Member] Line item in the statement of financial position in which the fair value amounts of the derivative instruments are included. Entity Emerging Growth Company Entity Emerging Growth Company 2028 Long-Term Debt, Maturity, Year Three Defined benefit plan, distribution of single Life annuity for joint and survivor (as percent) Defined Benefit Plan, Distribution Of Single Life Annuity For Joint And Survivor, Percentage Defined Benefit Plan, Distribution Of Single Life Annuity For Joint And Survivor, Percentage Accumulated other comprehensive income Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax Other operating expenses Fuel and oil Operating Expense [Member] Finance (in years) Finance Lease, Weighted Average Remaining Lease Term Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Gain on forward purchase agreement (Gain) Loss recognized in income on derivatives Derivative, Gain (Loss) on Derivative, Net 2026 Defined Benefit Plan, Expected Future Benefit Payment, Year One Less imputed interest Finance Lease, Liability, Undiscounted Excess Amount Renewal term (in years) Lessee, Renewal Term Lessee, Renewal Term Workforce Subject to Collective Bargaining Arrangements Workforce Subject to Collective-Bargaining Arrangements [Member] Disaggregation of Passenger Revenue Disaggregation of Revenue [Table Text Block] Vacation pay Accrued Vacation, Current CURRENT: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] The remaining balance of shares originally authorized for issue under the employee stock purchase plan (in shares) Stock Available For Issue Number Employee Stock Purchase Plan This element represents the remaining balance of shares originally authorized for issue under the employee stock purchase plan. Stock warrants repurchase Adjustments To Additional Paid In Capital, Warrants Repurchased Adjustments To Additional Paid In Capital, Warrants Repurchased Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Units (000) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date PROVISION FOR INCOME TAXES Less: Tax expense PROVISION FOR INCOME TAXES Income Tax Expense (Benefit) Spread on variable rate (as a percent) Debt Instrument, Basis Spread on Variable Rate Inventories of parts and supplies, at cost Airline Related Inventory, Gross Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Designated as Hedging Instrument Designated as Hedging Instrument [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Hedging Relationship [Axis] Hedging Relationship [Axis] Property and equipment, at cost Property, Plant and Equipment, Gross Schedule of Changes in Accumulated Market Based Cash Balance Plan and Postemployment Benefit Obligations Schedule of Changes in Accumulated Postemployment Benefit Obligations [Table Text Block] January 2026 ASR Program January 2026 ASR Program [Member] January 2026 ASR Program RESTRUCTURING Restructuring and Related Activities Disclosure [Text Block] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] U.S. federal Income Tax Paid, Federal, after Refund Received All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Other Other Customer [Member] Accrued liabilities Accrued liabilities Accrued Liabilities, Current DEFERRED TAX LIABILITIES: Deferred Tax Liabilities, Gross [Abstract] Outstanding RSU's - beginning balance (in shares) Outstanding RSU's - ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Term of contract (in years) Lessee Operating And Finance Lease Term Of Contract Lessee Operating And Finance Lease Term Of Contract Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Age and number of years of service Deferred Compensation Arrangement with Individual, Individual Age And Term Of Service Deferred Compensation Arrangement with Individual, Individual Age And Term Of Service Other Revenue Other Revenue [Member] Other Revenue Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract] Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract] Term (in years) Debt Instrument, Term Number of aircraft retirements Long-Term Purchase Commitment, Aircraft Retirements Long-Term Purchase Commitment, Aircraft Retirements Proceeds from portfolio termination Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Useful life (in years) Property, Plant and Equipment, Useful Life Subsequent Event Subsequent Event [Member] Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Proceeds from sales of short-term and other investments Proceeds from Sale of Short-Term Investments PEO Total Compensation Amount PEO Total Compensation Amount Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] 2029 Finance Lease, Liability, to be Paid, Year Four Gross amounts offset in the balance sheet Liability derivatives Derivative Liability, Subject to Master Netting Arrangement, before Offset Other (gains) losses, net Gain (Loss) on Derivative Instruments [Member] NUMERATOR: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Equity Components [Axis] Equity Components [Axis] Sublease income Sublease Income Convertible Notes Convertible Debt [Member] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Number of reportable segments Number of Reportable Segments Advertising Advertising Cost [Policy Text Block] Entity Address, State or Province Entity Address, State or Province Financing cash flows for finance leases Finance Lease, Principal Payments 2029 Defined Benefit Plan, Expected Future Benefit Payment, Year Four Total current liabilities Liabilities, Current Reduction of employees (as a percent) Restructuring and Related Cost, Number of Positions Eliminated, Period Percent Maintenance materials and repairs Aircraft Maintenance, Materials, and Repairs Air Traffic Liability [Roll Forward] Air Traffic Liability [Roll Forward] Air Traffic Liability Individual: Individual [Axis] Company contributions to all defined contribution plans expensed Defined Contribution Plan, Cost Change in Accounting Estimate [Line Items] Change in Accounting Estimate [Line Items] Included in other comprehensive income Fair Value, Recurring Basis, Unobservable Input Reconciliation, Asset (Liability), Gain (Loss), OCI Income Tax Authority [Domain] Income Tax Jurisdiction [Domain] Accounting Changes and Error Corrections [Abstract] Accounting Changes and Error Corrections [Abstract] Flight and ground equipment acquired or modified under finance leases Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Document Annual Report Document Annual Report Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Warranty Obligations Warranty Obligations [Member] Entity Interactive Data Current Entity Interactive Data Current RSU's - additional disclosures [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Business partners Business Partners, Current Business Partners, Current 1.000% Payroll Support Program Loan due 2031 1.0 Payroll Support Program Loan due April 2031 [Member] 1.0 Payroll Support Program Loan due April 2031 Current period sales Contract With Customer, Liability, Additions Contract With Customer, Liability, Additions Gain on terminated derivatives Derivative, Gain (Loss) On Derivatives Terminated Derivative, Gain (Loss) On Derivatives Terminated Funded status Defined Benefit Plan, Funded (Unfunded) Status of Plan Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Current maturities of long-term debt Less current maturities Long-Term Debt and Lease Obligation, Current Net operating losses and tax credits Deferred Tax Assets, Operating Loss Carryforwards Latin America Latin America [Member] Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] 4.375% Notes 4.375 Notes due 2028 [Member] 4.375 Notes due 2028 2027 Finance Lease, Liability, to be Paid, Year Two Accumulated amortization Finance Lease, Right-of-Use Asset, Accumulated Amortization 2027 Defined Benefit Plan, Expected Future Benefit Payment, Year Two Other assets Other assets Other Assets, Noncurrent Interest Interest Payable, Current Customer [Domain] Customer [Domain] Entity Central Index Key Entity Central Index Key Ground property and equipment Property, Plant and Equipment, Other, Gross PEO Name PEO Name Schedule of Maturities of Long-Term Debt Schedule of Maturities of Long-Term Debt [Table Text Block] Change in fair value, loss recognized Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Litigation settlement, period of differential pay benefit per year Litigation Settlement, Period of Differential Pay Benefit Per Year Litigation Settlement, Period of Differential Pay Benefit Per Year Beginning Balance Ending Balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Defined Benefit Plan [Table] Defined Benefit Plan [Table] Share-Based Payment Arrangement, Tranche One Share-Based Payment Arrangement, Tranche One [Member] Air traffic liability Contract with Customer, Liability, Current Nontaxable or nondeductible items Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount [Abstract] Schedule of Derivative Instruments in Statement of Financial Position, Fair Value Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid U.S. federal statutory tax Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Subsequent Event Type [Axis] Subsequent Event Type [Axis] Accrued expense on settlement Loss Contingency Accrual, Provision The discount percentage off the market value for the employee stock purchase plan (in hundredths) Discount Percentage Off Market Value For Shares Available Under Employee Stock Purchase Plan This element represents the discount off the market price for each purchase right under the employee stock purchase plan. Balance Sheet Location [Axis] Statement of Financial Position Location, Balance [Axis] Vesting [Domain] Vesting [Domain] Defined Benefit Plan, Assumptions Used in Calculations [Abstract] Defined Benefit Plan, Assumptions Used in Calculations [Abstract] Time deposits Bank Time Deposits [Member] DEFERRED TAX ASSETS: Deferred Tax Assets, Net [Abstract] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Entity Address, Address Line One Entity Address, Address Line One Accumulated other comprehensive income (loss) AOCI Attributable to Parent [Member] Average price paid per share (in USD per share) Weighted Average Fair Value Of Stock Purchase Right Under Employee Stock Purchase Plan This element represents the weighted average fair value of each purchase right under the employee stock purchase plan. Per diem Effective Income Tax Rate Reconciliation, Nondeductible Expense, Meals and Entertainment, Percent FINANCIAL DERIVATIVE INSTRUMENTS Derivative Instruments and Hedging Activities Disclosure [Text Block] Operating lease liabilities Deferred Tax Assets, Operating Lease Liability Deferred Tax Assets, Operating Lease Liability Fair Value as of Grant Date Award Grant Date Fair Value Compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Excess Compensation, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Excess Compensation, Percent Operating loss carryforwards Operating Loss Carryforwards Insurance Reserves Insurance, Long-Duration Contract [Policy Text Block] Changes in unrecognized tax benefits Effective Income Tax Rate Reconciliation, Tax Contingency, Amount Schedule of Long-term Debt Instruments Schedule of Long-Term Debt Instruments [Table Text Block] Salaries, wages, and benefits Labor and Related Expense Dilutive effect of restricted stock units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Surrendered (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Total unrecognized compensation cost related to share-based compensation arrangements Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount DOT settlement Effective Income Tax Rate Reconciliation, Tax Settlement, Amount Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] 2027 Lessee, Operating Lease, Liability, to be Paid, Year Two Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount 2028 Defined Benefit Plan, Expected Future Benefit Payment, Year Three Impairments Impairment of Long-Lived Assets to be Disposed of Non-PEO NEO Non-PEO NEO [Member] Outstanding letters of credit Letters of Credit Outstanding, Amount Operating lease right-of-use assets Deferred Tax Liabilities, Leasing Arrangements Prepaid maintenance Prepaid Maintenance Prepaid Maintenance Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Other Intangible Assets Other Intangible Assets [Member] Schedule of Offsetting Assets Offsetting Assets [Table Text Block] Share-based compensation arrangements by share-based payment award, award type and plan name [Domain] Award Type [Domain] Early prepayments made on debt Payment for Debt Extinguishment or Debt Prepayment Cost 2026 Lessee, Operating Lease, Liability, to be Paid, Year One Equity Awards Adjustments Equity Awards Adjustments [Member] Advertising costs Advertising Expense Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Effect of cross-border tax laws Effective Income Tax Rate Reconciliation, Cross-Border Tax Effect, Percent Weighted average remaining lease term Weighted Average Remaining Lease Term [Abstract] Weighted Average Remaining Lease Term Disaggregation of Revenue Disaggregation of Revenue [Line Items] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Accounts and other receivables Increase (Decrease) in Accounts and Other Receivables Compensation Amount Outstanding Recovery Compensation Amount DEFERRED: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] 2031 Unrecorded Unconditional Purchase Obligation, to be Paid, after Year Five Voluntary Separation Program and severance pay Accrued Voluntary Separation Program And Severance Pay, Current Accrued Voluntary Separation Program And Severance Pay, Current Other adjustments Effective Income Tax Rate Reconciliation, Other Reconciling Items, Percent Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Aircraft Air Transportation Equipment [Member] Aircraft Aircraft [Member] Aircraft Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Revenue from amounts included in contract liability opening balances Contract with Customer, Liability, Revenue Recognized Offsetting Assets [Table] Offsetting Assets [Table] Retirement Plan Type [Domain] Retirement Plan Type [Domain] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Foreign tax effects Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Total 5.125 Notes due 2027 Total 5.125 Notes due 2027 [Member] Total 5.125 Notes due 2027 Termination period (in months) Share-Based Compensation Arrangement By Share-Based Payment Award, Award Vesting Rights, Termination Period Share-Based Compensation Arrangement By Share-Based Payment Award, Award Vesting Rights, Termination Period DENOMINATOR: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] OPERATING REVENUES: Revenues [Abstract] Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Reinsurance payable and losses payable Reinsurance Payable And Losses Payable, Current Reinsurance Payable And Losses Payable, Current Tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Amount [Abstract] Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Long-term debt less current maturities Long-Term Debt and Lease Obligation 2026 Long-Term Debt, Maturity, Year One Total deferred tax liabilities Deferred Tax Liabilities, Gross Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block] Award Date [Domain] Award Date [Domain] 2030 Long-Term Debt, Maturity, Year Five Performance Shares Performance Shares [Member] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Defined benefit plan, eligible wages (as percent) Defined Benefit Plan, Eligible Wages, Percentage Defined Benefit Plan, Eligible Wages, Percentage Other Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount Minimum Minimum [Member] 1.000% Payroll Support Program Loan due 2031 1.0 Payroll Support Program Loan due January 2031 [Member] 1.0 Payroll Support Program Loan due January 2031 Company Selected Measure Name Company Selected Measure Name FINANCING ACTIVITIES Debt Disclosure [Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Accounts payable Accounts payable Accounts Payable, Current Operating cash flows for operating leases Operating Lease, Payments Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Dividends payable Dividends Payable Loyalty points, redemption period (in years) Revenue From Contracts With Customers, Loyalty Program, Redemption Period Revenue From Contracts With Customers, Loyalty Program, Redemption Period 7.375% Debentures 7.375 Debentures due 2027 [Member] 7.375 Debentures due 2027 COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Share-Based Payment Arrangement, Tranche Two Share-Based Payment Arrangement, Tranche Two [Member] Adjusted weighted-average shares outstanding, diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Receivable from third parties for fuel contracts Derivative, Cash Receivable (Payable) On Hedge Derivative, Cash Receivable (Payable) On Hedge Operating Segments and Related Disclosures Segment Reporting, Policy [Policy Text Block] Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Derivative [Table] Derivative [Table] Entity Small Business Entity Small Business Reimbursement costs Customer Expense Reimbursements And Other Miscellaneous Expenses Customer Expense Reimbursements And Other Miscellaneous Expenses Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Other operating expenses Other Cost and Expense, Operating State Current State and Local Tax Expense (Benefit) Document Transition Report Document Transition Report Proceeds of terminated interest rate derivative instruments Proceeds of Terminated Interest Rate Derivative Instruments Proceeds of Terminated Interest Rate Derivative Instruments Total lease payments Finance Lease, Liability, to be Paid Underlying Securities Award Underlying Securities Amount Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] INCOME TAXES Income Tax Disclosure [Text Block] Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Short-term lease cost Short-Term Lease, Cost 2.0 Payroll Support Program Loan due 2031 2.0 Payroll Support Program Loan due 2031 [Member] 2.0 Payroll Support Program Loan due 2031 Other deferred compensation Other Deferred Compensation Arrangements, Liability, Classified, Noncurrent Shares repurchased, average purchase price per share (in USD per share) Shares Acquired, Average Cost Per Share Number of aircraft deliveries Long-Term Purchase Commitment, Aircraft Deliveries Long-Term Purchase Commitment, Aircraft Deliveries Document Type Document Type Significant unobservable inputs (Level 3) Level 3 Fair Value, Inputs, Level 3 [Member] NET INCOME PER SHARE Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Product and Service [Axis] Product and Service [Axis] Accounts and other receivables Accounts and other receivables Accounts and Other Receivables, Net, Current Variable lease cost Variable Lease, Cost Other deferred taxes Other Comprehensive Income, Other, Tax Other Comprehensive Income, Other, Tax Total operating revenues Breakage revenue adjustment Operating revenues (reversal of revenue) Revenue from Contract with Customer, Excluding Assessed Tax Effect of Change in Accounting Estimate, Type [Domain] Effect of Change in Accounting Estimate, Type [Domain] Fuel payable Fuel Payable Carrying value as of the balance sheet date of obligations incurred and payable for fuel. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Total current assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Percentage of PBRSUs to be granted Percentage Of PBRSUs To Be Granted Percentage Of PBRSUs To Be Granted Amount authorized under share repurchase program Share Repurchase Program, Authorized, Amount Other Other Receivables, Net, Current Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Schedule of Other Assets Schedule of Other Assets [Table Text Block] Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Net income attributable to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Current liabilities: Liabilities, Current [Abstract] Research and development tax credit carryforwards Deferred tax asset for research and development tax credits Deferred Tax Assets, Tax Credit Carryforwards, Research 2.625% Notes 2.625 Unsecured Senior Notes Due 2030 [Member] 2.625 Unsecured Senior Notes Due 2030 Schedule of Derivative Instruments, Gain (Loss) Derivative Instruments, Gain (Loss) [Table Text Block] Quoted prices in active markets for identical assets (Level 1) Fair Value, Inputs, Level 1 [Member] Number of airframe purchase agreements Number Of Airframe Purchase Agreements Number Of Airframe Purchase Agreements NET INCOME PER SHARE, DILUTED (in USD per share) Net income per diluted share (in dollars per share) Diluted (in USD per share) Earnings Per Share, Diluted Other credits Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount Trade receivables Accounts Receivable, after Allowance for Credit Loss, Current Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] SUPPLEMENTAL DISCLOSURE OF NON-CASH TRANSACTIONS: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Schedule of Assumptions Used Defined Benefit Plan, Assumptions [Table Text Block] Treasury stock, at cost (in shares) Treasury Stock, Common, Shares State Income Tax Paid, State and Local, after Refund Received Derivative Liability, Statement of Financial Position [Extensible Enumeration] Derivative Liability, Statement of Financial Position [Extensible Enumeration] Auditor Location Auditor Location Weighted average discount rate Weighted Average Discount Rate [Abstract] Weighted Average Discount Rate Actuarial losses Actuarial (gain) loss Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Domestic Tax Authority Domestic Tax Jurisdiction [Member] Plan Amendments Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Less imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Schedule of Accounts Payable Schedule Of Accounts Payable [Table Text Block] Tabular disclosure of the components of accounts payable. Gross carrying amount of indefinite-lived intangible assets Indefinite-Lived Domestic Slots and Routes Total cash paid for income taxes (net of refunds) Income Taxes Paid, Net Other Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent Cash Equivalents Cash Equivalents [Member] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Number of votes per share Common Stock, Number Of Votes Per Share Common Stock, Number Of Votes Per Share Long term debt Carrying value Long-Term Debt, Gross Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Total lease payments Lessee, Operating Lease, Liability, to be Paid Total Gain (Loss) on Derivative Instruments, Net, Pretax Expiration Date Trading Arrangement Expiration Date Grant Year 2023 Grant Year 2023 [Member] Grant Year 2023 Other liabilities Increase (Decrease) in Other Operating Liabilities Derivative, average variable interest rate Derivative, Average Variable Interest Rate Property and equipment, net Property, Plant and Equipment, Net Restructuring charges Restructuring Charges 3.0 Payroll Support Program Loan due 2031 3.0 Payroll Support Program Loan due 2031 [Member] 3.0 Payroll Support Program Loan due 2031 2026 Unrecorded Unconditional Purchase Obligation, to be Paid, Year One Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Inventories Inventory, Policy [Policy Text Block] Entity Current Reporting Status Entity Current Reporting Status Derivative [Line Items] Derivative [Line Items] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] U.S. federal statutory tax Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Executive Category: Executive Category [Axis] Early repayments of loan Repayments of Debt State and local income taxes, net of federal income tax effect Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Fourth Quarter 2025 ASR Program Fourth Quarter 2025 ASR Program [Member] Fourth Quarter 2025 ASR Program Finance Less current obligations Finance Lease, Liability, Current Grant Year 2024 Grant Year 2024 [Member] Grant Year 2024 Current Fiscal Year End Date Current Fiscal Year End Date Assumed healthcare cost trend rate Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity Schedule of Share-Based Compensation, Employee Stock Purchase Plan, Activity [Table Text Block] Aircraft Type [Axis] Aircraft Type [Axis] Schedule of Accounts and Other Receivables Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Wtd. Average Fair Value (per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Common stock reserved for issuance and not granted pursuant to Employee stock benefit plans (in shares) The remaining number of RSU's or stock options that may be issued (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant Net amounts of liabilities presented in the Balance Sheet Derivative Liability Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table] Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Total lease liabilities Lease Liability Lease Liability Interest rate derivative contracts Interest Rate Contract [Member] Delivery [Domain] Delivery [Domain] Delivery [Domain] The percentage of market value at which shares may be issued to participating employees (as a percent) Percentage Of Market Value For Shares Available Under Employee Stock Purchase Plan This element represents the percentage of market price at which shares may be issued to employees participating in the employee stock purchase plan. Effect of changes in tax laws or rates enacted in the current period Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Total Unrecorded Unconditional Purchase Obligation 2027 Long-Term Debt, Maturity, Year Two Other Commitments [Table] Other Commitments [Table] LEASES Lessee, Operating Leases [Text Block] Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Measure: Measure [Axis] Revenue from contract with customer, number of performance obligations Revenue From Contract With Customer, Number Of Performance Obligations Revenue From Contract With Customer, Number Of Performance Obligations Capital commitments 2027 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Two SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation and Significant Accounting Policies [Text Block] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] Schedule of Reclassification out of Accumulated Other Comprehensive Income (Loss) Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Non-cash amortization of debt issuance costs Amortization of Debt Issuance Costs Entity Tax Identification Number Entity Tax Identification Number 1.25% Convertible Notes 1.250 Convertible Senior Notes due 2025 [Member] 1.250 Convertible Senior Notes due 2025 New York Fed Bank Rate New York Fed Bank Rate [Member] New York Fed Bank Rate [Member] Accounts payable trade Accounts Payable, Trade, Current Common stock, shares issued (in shares) Common Stock, Shares, Issued Derivative Asset, Statement of Financial Position [Extensible Enumeration] Derivative Asset, Statement of Financial Position [Extensible Enumeration] Operating (in years) Operating Lease, Weighted Average Remaining Lease Term 2029 Long-Term Debt, Maturity, Year Four Entity Public Float Entity Public Float Interest expense Interest Expense, Nonoperating Trading Arrangement: Trading Arrangement [Axis] Forward purchase agreement asset Derivative Asset, Current Boeing 737-800 Boeing 737-800 [Member] Boeing 737-800 Total Shareholder Return Amount Total Shareholder Return Amount Air traffic liability - loyalty program Air traffic liability - loyalty program - beginning balance Air traffic liability - loyalty program - ending balance Contract With Customer Liability, Air Traffic Liability, Loyalty Program Contract With Customer Liability, Air Traffic Liability, Loyalty Program Unrecognized net actuarial gain Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax Security Exchange Name Security Exchange Name Maximum age after retirement that employees may use accrued unused sick time to pay for medical and dental premiums Defined Contribution Pension Plans Maximum Age Requirement For Paying Medical And Dental Premiums With Accrued Unused Sick Time Maximum age after retirement that employees may use accrued unused sick time to pay for medical and dental premiums if they meet minimum levels of service and age requirements set forth by the company or as specified in collective bargaining agreements. DOT waived final settlement Legal Settlements, Payments Waived Legal Settlements, Payments Waived Noncurrent Lease Liabilities, Noncurrent [Abstract] Lease Liabilities, Noncurrent Capitalized computer software, net Capitalized Computer Software, Net Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] Aircraft and Engine Maintenance Maintenance Cost, Policy [Policy Text Block] Deferred supplier credits Supplier Finance Program, Obligation, Current Number of aircraft sale agreements Sale Leaseback Transaction, Number Of Aircraft Sale Agreements Sale Leaseback Transaction, Number Of Aircraft Sale Agreements Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-Lived Intangible Assets, Major Class Name [Domain] Vesting rights, minimum percentage (as a percent) Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Minimum Percentage Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Minimum Percentage Weighted-average discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Postretirement obligation Liability, Defined Benefit Plan, Noncurrent Statement [Line Items] Statement [Line Items] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Cash and cash equivalents Cash and Cash Equivalent Passenger ancillary sold separately Passenger Ancillary Sold Separately [Member] Passenger Ancillary Sold Separately Deferred income taxes Increase (Decrease) in Deferred Income Taxes Common Stock Common Stock [Member] Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Finance leases Finance Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] NET CHANGE IN CASH AND CASH EQUIVALENTS Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Statistical Measurement [Domain] Statistical Measurement [Domain] Thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Five Proceeds from sale-leaseback transactions Sale Leaseback Cash Proceeds Investing Sale Leaseback Cash Proceeds Investing Number of claims alleged in litigation case Number Of Claims Alleged In Litigation Case Number Of Claims Alleged In Litigation Case Interest rate swap Interest rate derivative contracts Interest Rate Swap [Member] Leases [Abstract] Leases [Abstract] NET INCOME PER SHARE: Earnings Per Share, Basic [Abstract] Third Quarter 2025 ASR Program Third Quarter 2025 ASR Program [Member] Third Quarter 2025 ASR Program Schedule of Other Noncurrent Liabilities Other Noncurrent Liabilities [Table Text Block] Loyalty Program Frequent Flier Program, Policy [Policy Text Block] Schedule of Capital Commitments Unrecorded Unconditional Purchase Obligations Disclosure [Table Text Block] Unionized Employees concentration risk Unionized Employees Concentration Risk [Member] Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] NET INCOME PER SHARE, BASIC (in USD per share) Net income per basic share (in dollars per share) Basic (in USD per share) Earnings Per Share, Basic Sale leaseback transaction, lease term (in years) Sale Leaseback Transaction, Lease Term Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Liabilities Liabilities, Fair Value Disclosure [Abstract] Common stock reserved for issuance pursuant to employee stock benefit plans (in shares) Common Stock, Capital Shares Reserved for Future Issuance Changes in unrecognized tax benefits Effective Income Tax Rate Reconciliation, Tax Contingency, Percent Award Date [Axis] Award Date [Axis] OTHER COMPREHENSIVE INCOME (LOSS) Other Comprehensive Income (Loss), Net of Tax Payments of long-term debt and finance lease obligations Payments of long-term debt and finance lease obligations Repayments Of Other Long-Term Debt And Finance Lease Obligations Repayments Of Other Long-Term Debt And Finance Lease Obligations Revenue recognized from points redeemed Contract With Customer, Liability, Loyalty Program, Revenue Recognized Contract With Customer, Liability, Loyalty Program, Revenue Recognized 2028 Finance Lease, Liability, to be Paid, Year Three Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Other Accumulated Other Adjustments Attributable to Parent [Member] Accumulated Other Adjustments Attributable to Parent Changes in fair value OCI, before Reclassifications, Net of Tax, Attributable to Parent Derivative Instruments, (Gain) Loss Derivative Instruments, Gain (Loss) [Line Items] Share based compensation cost Share-Based Payment Arrangement, Expense Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Hedging Designation [Domain] Hedging Designation [Domain] Estimated fair value Notes Payable, Fair Value Disclosure Fair Value, Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Litigation settlement, period of fund and relief Litigation Settlement, Period of Fund and Relief Litigation Settlement, Period of Fund and Relief Current assets: Assets, Current [Abstract] Total liabilities and stockholders' equity Liabilities and Equity Defined benefit plan items Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Derivative Instruments, (Gain) Loss by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table] Derivative Instruments, Gain (Loss) [Table] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification to earnings Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Other Deferred Tax Assets, Other Accounting Policies [Abstract] Accounting Policies [Abstract] Operating Lease Maturity Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block] Forward Purchase Agreement Forward Contracts [Member] MAX MAX [Member] MAX Concentration Risk Type [Domain] Concentration Risk Type [Domain] William P. Hobby Airport William P. Hobby Airport [Member] William P. Hobby Airport Treasury stock Treasury Stock, Common [Member] Per diem Effective Income Tax Rate Reconciliation, Nondeductible Expense, Meals and Entertainment, Amount Pay vs Performance Disclosure [Line Items] Payroll Support Program stock warrants repurchase Payroll Support Program, Warrants Repurchased Payroll Support Program, Warrants Repurchased Operating lease, liability Total lease obligations Operating Lease, Liability Estimated fair value Loans Payable, Fair Value Disclosure Share Repurchase Program [Line Items] Share Repurchase Program [Line Items] Aircraft maintenance payable Aircraft Maintenance Payable Carrying value as of the balance sheet date of obligations incurred and payable for aircraft maintenance. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Depreciation and amortization Depreciation and amortization expense Depreciation, Depletion and Amortization, Nonproduction Amortization of finance lease assets Finance Lease, Right-of-Use Asset, Amortization Other noncurrent liabilities Other Liabilities, Noncurrent Property and income taxes Accrual for Taxes Other than Income Taxes, Current Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer 2028 Lessee, Operating Lease, Liability, to be Paid, Year Three Bonus pay Accrued Bonuses, Current Less debt discount and issuance costs Debt Issuance Costs, Gross COMPREHENSIVE INCOME Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Name Measure Name Deferred income taxes Deferred Income Tax Liabilities, Net Weighted average expected long-term rate of return Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets 5.125% Notes 5.125 Notes due 2027 [Member] 5.125 Notes due 2027 Unsecured Debt Unsecured Debt [Member] Total long term debt Long-Term Debt Legal Entity [Axis] Legal Entity [Axis] Total assets Assets Vested (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Geographical [Domain] Geographical [Domain] Landing fees and airport rentals Landing Fees and Other Rentals Income Taxes Income Tax, Policy [Policy Text Block] CASH FLOWS FROM OPERATING ACTIVITIES: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Research and development tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent Revenue from current period sales Contract With Customer, Liability, Revenue Recognized, Current Period Contract With Customer, Liability, Revenue Recognized, Current Period Concentration Risk Type [Axis] Concentration Risk Type [Axis] Year 2024 & 2025 Year 2024 & 2025 [Member] Year 2024 & 2025 Year 2025 Year 2025 [Member] Year 2025 2026 Finance Lease, Liability, to be Paid, Year One Cash dividends, per share (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Right-of-use assets acquired or modified under operating leases Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Level 2 Significant other observable inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Document Financial Statement Error Correction [Flag] Document Financial Statement Error Correction [Flag] State and local income taxes, net of federal income tax effect Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Fair Value, off-Balance-Sheet Risks, Disclosure Information [Line Items] Airport-Related Airport-Related [Member] Airport-Related [Member] Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Operating leases Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Gain (loss) on termination of lease Gain (Loss) on Termination of Lease Schedule of Components of the Income Tax Provision Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] PEO PEO [Member] Interest income Investment Income, Interest Changes in certain assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Unrecorded Unconditional Purchase Obligation [Line Items] Unrecorded Unconditional Purchase Obligation [Line Items] Changes in valuation allowances Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Accelerated depreciation Deferred Tax Liabilities, Property, Plant and Equipment Retained earnings Retained Earnings [Member] Income Tax Authority [Axis] Income Tax Jurisdiction [Axis] Schedule of Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Share-based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD CASH AND CASH EQUIVALENTS AT END OF PERIOD Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Income Statement [Abstract] Net amounts of assets presented in the Balance Sheet Derivative Asset Not Designated as Hedging Instrument, Economic Hedge Not Designated as Hedging Instrument, Economic Hedge [Member] Ticket taxes and fees Taxes Payable, Current Certificates of deposit Investments, Fair Value Disclosure Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Service Life Service Life [Member] Product and Service [Domain] Product and Service [Domain] Add: Interest expense Interest on Convertible Debt, Net of Tax Contractual coupon interest Interest Expense, Debt, Excluding Amortization Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Cash paid for amounts included in the measurement of lease liabilities: Cash Flow, Operating Activities, Lessee [Abstract] Length of agreements with co-brand, payment, and loyalty partners (in years) Maximum Length Of Agreements With Co-Brand, Payment, And Loyalty Partners Maximum Length Of Agreements With Co-Brand, Payment, And Loyalty Partners City Area Code City Area Code Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Rollforward of Air Traffic Liability Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Net deferred tax liability Deferred Tax Liabilities, Net CASH FLOWS FROM INVESTING ACTIVITIES: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Amortization of net gain Defined Benefit Plan, Amortization of Gain (Loss) Total net lease cost Lease, Cost Equity securities Equity Securities, FV-NI Cash Flow Hedging Cash Flow Hedging [Member] Goodwill Goodwill Components of Lease Cost Lease, Cost [Table Text Block] Prepaid expenses and other current assets Prepaid Expenses and Other Current Assets [Member] Service cost Defined Benefit Plan, Service Cost, Excluding Initial Funding Defined Benefit Plan, Service Cost, Excluding Initial Funding Federal Deferred Federal Income Tax Expense (Benefit) Auditor Name Auditor Name Workers compensation Workers' Compensation Liability, Current Flight equipment Flight Equipment, Gross Defined Benefit Plan, Expected Future Benefit Payment [Abstract] Defined Benefit Plan, Expected Future Benefit Payment [Abstract] CASH PAYMENTS FOR: Supplemental Cash Flow Information [Abstract] Other Performance Measure, Amount Other Performance Measure, Amount New airport gates Number Of Airport Gates Number Of Airport Gates Amount Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract] Capitalized interest Interest Costs Capitalized Adjustment Derivative Instrument [Axis] Derivative Instrument [Axis] Benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Vesting [Axis] Vesting [Axis] Financial Derivative Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] LEASES Lessee, Finance Leases [Text Block] Capital in excess of par value Additional Paid in Capital, Common Stock Effect of Change in Accounting Estimate, Type [Axis] Effect of Change in Accounting Estimate, Type [Axis] Entity [Domain] Entity [Domain] Net cash used in investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Derivative contracts Derivative Asset, Noncurrent Interest, net of amount capitalized Interest Paid, Excluding Capitalized Interest, Operating Activity Document Fiscal Year Focus Document Fiscal Year Focus Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Operating lease right-of-use assets Operating Operating Lease, Right-of-Use Asset Health Accrued Employee Benefits, Current Total income tax provision Effective Income Tax Rate Reconciliation, Percent Operating lease cost Operating Lease, Cost Cash collateral provided to derivative counterparties Increase (Decrease) Cash Collateral from Counterparties Fuel derivatives: Fuel derivative assets [Abstract] -- None. No documentation exists for this element. -- Number of aircrafts sold Sale Leaseback Transaction, Number Of Aircrafts Sold Sale Leaseback Transaction, Number Of Aircrafts Sold Weighted average period of time over which unrecognized compensation cost is to be recognized (in years) Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Excess Compensation, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Excess Compensation, Amount Valuation allowance Valuation allowance Deferred Tax Assets, Valuation Allowance Equity [Abstract] Equity [Abstract] North America North America [Member] Minimum employee service period (in years) Deferred Compensation Arrangement with Individual, Requisite Service Period Goodwill and Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Financial Derivative Instruments Derivatives, Policy [Policy Text Block] 2028 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Three Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Not Designated as Hedging Instrument Not Designated as Hedging Instrument [Member] 5.250% Notes 5.250 Notes due 2035 [Member] 5.250 Notes due 2035 Schedule of Amounts Recognized in Balance Sheet Schedule of Amounts Recognized in Balance Sheet [Table Text Block] Fair value of plan assets at beginning of period Fair value of plan assets at end of period Defined Benefit Plan, Plan Assets, Amount Federal Current Federal Tax Expense (Benefit) Other Commitments [Line Items] Other Commitments [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Reduction of employees Restructuring and Related Cost, Expected Number of Positions Eliminated Delivery [Axis] Delivery [Axis] Delivery Ground property and equipment Other Capitalized Property Plant and Equipment [Member] Schedule of Net Benefit Costs Schedule of Net Benefit Costs [Table Text Block] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Comprehensive Income (Loss) Note [Text Block] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Leases Lessee, Leases [Policy Text Block] Schedule of Rollforward of the Amounts Included in AOCI, Net of Taxes Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Capital expenditures, net Capital expenditures Payments to Acquire Productive Assets Payments for airport projects Payments for Capital Improvements Number of leased aircrafts, operating lease Number Of Leased Aircrafts, Operating Lease Number Of Leased Aircrafts, Operating Lease Dilutive effects of convertible notes (in shares) Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities Revolving Credit Facility Revolving Credit Facility [Member] Foreign tax effects Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Finance leases Total lease obligations Total lease obligations Finance Lease, Liability Arrangement Duration Trading Arrangement Duration Other Other Sundry Liabilities, Noncurrent B-737-700 B-737-700 [Member] Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Other, net of deferred taxes of $1, $3, and $8 Other Comprehensive Income, Other, Net of Tax Aircraft Residual Value Aircraft Residual Value [Member] Aircraft Residual Value Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] First Quarter 2025 ASR Program First Quarter 2025 ASR Program [Member] First Quarter 2025 ASR Program Other, net Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Other Item Thereafter Long-Term Debt, Maturity, after Year Five STOCK PLANS Share-Based Payment Arrangement [Text Block] Payroll support programs Number Of Payroll Support Programs Number Of Payroll Support Programs 1.000% Payroll Support Program Loan due 2030 1.0 Payroll Support Program Loan due 2030 [Member] 1.0 Payroll Support Program Loan due 2030 Air traffic liability - passenger travel and ancillary passenger services Contract With Customer Liability, Air Traffic Liability, Service Revenue Contract With Customer Liability, Air Traffic Liability, Passenger Travel And Ancillary Passenger Services ASSETS Assets Assets [Abstract] Credit Facility [Axis] Credit Facility [Axis] Other Other Contract [Member] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Debt Instrument [Axis] Debt Instrument [Axis] Surrendered (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value EMPLOYEE RETIREMENT PLANS Retirement Benefits [Text Block] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Credit Facility [Domain] Credit Facility [Domain] Stockholders' equity: Equity, Attributable to Parent [Abstract] Vesting percentage (as a percent) Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage Repurchase of common stock Treasury Stock, Value, Acquired, Cost Method Interest rate stated in the debt agreement (as a percent) Debt Instrument, Interest Rate, Stated Percentage Noncurrent operating lease liabilities Operating Operating Lease, Liability, Noncurrent Entity Voluntary Filers Entity Voluntary Filers Issuance of common and treasury stock pursuant to Employee stock plans Stock Issued During Period, Value, Employee Stock Plans Stock Issued During Period, Value, Employee Stock Plans Flight equipment Flight Equipment [Member] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Third party services Accrued Third Party Services Accrued Third Party Services Asset derivatives Option contracts Derivative Asset, Subject to Master Netting Arrangement, before Offset Entity Registrant Name Entity Registrant Name Passenger Passenger Customers [Member] Passenger Customers Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Net periodic postretirement benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Employee service share based compensation aggregate disclosures [Abstract] Share-Based Payment Arrangement, Additional Disclosure [Abstract] Computer software depreciation expense Capitalized Computer Software, Amortization Profit-sharing and savings plans Deferred Compensation Cash-Based Arrangements, Liability, Current Lease-Related Assets and Liabilities Lease-Related Assets and Liabilities [Table Text Block] Lease-Related Assets and Liabilities Second Quarter 2025 ASR Program Second Quarter 2025 ASR Program [Member] Second Quarter 2025 ASR Program Number of aircraft purchase agreements Number Of Aircraft Purchase Agreements Number Of Aircraft Purchase Agreements Total assets Assets, Fair Value Disclosure Non-option equity instruments granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted Number of operating segments Number of Operating Segments Expense recognized in income on derivatives Derivative, Cost of Hedge Interest cost Defined Benefit Plan, Interest Cost Granted (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Percent [Abstract] Unrecorded Unconditional Purchase Obligation [Table] Unrecorded Unconditional Purchase Obligation [Table] Other noncurrent liabilities Other Noncurrent Liabilities [Member] Restatement Determination Date: Restatement Determination Date [Axis] Modification of contract Contract With Customer, Liability, Adjustment, Modification of Contract Contract With Customer, Liability, Adjustment, Modification of Contract Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Assets constructed for others Assets Constructed For Others Assets Constructed For Others Other, net Proceeds from (Payment for) Other Financing Activity Total interest expense Interest Expense, Debt Effect of changes in tax laws or rates enacted in the current period Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Name Trading Arrangement, Individual Name Amount of loss remaining in AOCI related to closed fuel hedging contracts Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax Face amount of debt Debt Instrument, Face Amount Deferred taxes on postretirement Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Total operating expenses Operating Costs and Expenses Deferred Tax Asset, Valuation Allowance [Table] Deferred Tax Asset, Valuation Allowance [Table] Number of aircrafts purchased Number Of Aircrafts Purchased Number Of Aircrafts Purchased Name Awards Close in Time to MNPI Disclosures, Individual Name Beginning balance (in USD per share) Ending balance (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Share-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Finance Lease Maturity Finance Lease, Liability, to be Paid, Maturity [Table Text Block] Unsecured Senior Notes Due 2027 - 3.45% Unsecured Senior Notes Due 2027 [Member] Unsecured, Senior debt obligation due in 2027. Unsecured debt is not collateralized by pledge, mortgage or other lien in the entity's assets. Senior notes have the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders. Fixed Income Funds Fixed Income Funds [Member] Changes in fair value, deferred tax impact Other Comprehensive Income (Loss) before Reclassifications, Tax 5.125 Unsecured Notes due 2027 5.125 Unsecured Notes due 2027 [Member] 5.125 Unsecured Notes due 2027 Auditor Firm ID Auditor Firm ID Income Statement Location [Axis] Statement of Income Location, Balance [Axis] 3.45% Notes 3.45 Unsecured Senior Notes due 2027 [Member] 3.45 Unsecured Senior Notes due 2027 Accumulated Benefit Obligation at beginning of period Accumulated Benefit Obligation at end of period Defined Benefit Plan, Benefit Obligation Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Balance Sheet Location [Domain] Statement of Financial Position Location, Balance [Domain] Fuel and oil Fuel And Oil [Member] Fuel And Oil Other credits Effective Income Tax Rate Reconciliation, Tax Credit, Other, Percent Net Income Per Share Earnings Per Share, Policy [Policy Text Block] Less allowance for depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Debt and lease obligation Long-Term Debt and Lease Obligation, Including Current Maturities Gross amounts offset in the Balance Sheet Derivative Liability, Subject to Master Netting Arrangement, Asset Offset Proceeds from Employee stock plans Proceeds from Stock Plans All Executive Categories All Executive Categories [Member] Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Common stock, $1.00 par value: 2,000,000,000 shares authorized; 888,111,634 shares issued in 2025 and 2024 Common Stock, Value, Issued Finance Finance Lease, Right-of-Use Asset, after Accumulated Amortization Passenger loyalty - air transportation Passenger Loyalty, Air Transportation [Member] Passenger Loyalty Air Transportation [Member] Short-term investments Short-Term Investments Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Accounting Standards Update and Change in Accounting Principle [Table] Passenger non-loyalty Passenger Revenue, Non-Loyalty [Member] Passenger Revenue Non Loyalty [Member] Interest rate derivative liability Interest rate derivatives (see Note 10) Interest Rate Derivative Liabilities, at Fair Value Valuation Allowance [Line Items] Valuation Allowance [Line Items] NEW ACCOUNTING PRONOUNCEMENTS AND ACCOUNTING CHANGES Accounting Standards Update and Change in Accounting Principle [Text Block] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Amended 364-Day Term Loan Credit Facility Amended 364-Day Term Loan Credit Facility [Member] Amended 364-Day Term Loan Credit Facility [Member] DOT settlement Effective Income Tax Rate Reconciliation, Tax Settlement, Percent Liabilities Lease Liabilities [Abstract] Lease Liabilities Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Impairment of long-lived assets Gain (Loss) on Sale of Assets and Asset Impairment Charges Hedging Designation [Axis] Hedging Designation [Axis] Scenario [Axis] Scenario [Axis] Aircraft maintenance Accrued Aircraft Maintenance, Current Accrued Aircraft Maintenance, Current Unrealized gain (loss) on defined benefit plan items, net of deferred taxes of ($14), $4, and ($5) Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Amount of loss reclassified from AOCI into income Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Accelerated Share Repurchases, Date [Axis] Accelerated Share Repurchases, Date [Axis] Derivative Contract [Domain] Derivative Contract [Domain] 2030 Defined Benefit Plan, Expected Future Benefit Payment, Year Five All Individuals All Individuals [Member] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Unrealized mark-to-market adjustment on forward contract Unrealized Gain (Loss) On Derivatives, Net Of Tax And Profit Sharing Impacts Unrealized Gain (Loss) On Derivatives, Net Of Tax And Profit Sharing Impacts Deposits on flight equipment purchase contracts Deposits on Flight Equipment Name Forgone Recovery, Individual Name Unrealized mark-to-market adjustment on forward contract Unrealized Gain (Loss) on Derivatives 2029 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Four Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Defined Benefit Plan, Equity Securities Defined Benefit Plan, Equity Securities [Member] Schedule of Premiums Paid for Fuel Derivative Contracts Schedule of Derivative Instruments [Table Text Block] Deferred co-brand revenue Contract with Customer Liability, Loyalty Co-Branding, Noncurrent Contract with Customer Liability, Loyalty Co-Branding, Noncurrent Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Deferred tax impact, beginning balance Deferred tax impact, ending balance AOCI Tax, Attributable to Parent Geographical [Axis] Geographical [Axis] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Year 2026 Year 2026 [Member] Year 2026 LEASES Lessor, Operating Leases [Text Block] B-737-800 B-737-800 [Member] Maximum percentage of cost estimated as residual value (as a percent) Property Plant And Equipment Percentage Cost To Residual Value Maximum The maximum percentage of cost used to determine the residual value of long lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land and improvements, buildings, and production equipment. Forecast Forecast [Member] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Title of 12(b) Security Title of 12(b) Security Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Other adjustments Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount Number of leased aircrafts, finance lease Number Of Leased Aircrafts, Finance Lease Number Of Leased Aircrafts, Finance Lease Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] 737 MAX 8 B-737-8MAX [Member] B737-8MAX Earnings Per Share [Abstract] Earnings Per Share [Abstract] 2030 Lessee, Operating Lease, Liability, to be Paid, Year Five Projected airport improvement costs Projected Capital Improvement Costs Projected Capital Improvement Costs Total non-operating expenses (income) Nonoperating Income (Expense) Loyalty program and flight credit liability Deferred Tax Assets, Frequent Flier Liability Schedule of Interest Income and Interest Expense Disclosure Interest Income and Interest Expense Disclosure [Table Text Block] Air traffic liability Increase (Decrease) in Contract with Customer, Liability Other payable Accounts Payable, Other, Current Equity securities Equity Securities, FV-NI, Noncurrent Other Other Transportation Equipment [Member] Shares acquired in repurchase (in shares) Treasury Stock, Shares, Acquired Accelerated Share Repurchases, Date [Domain] Accelerated Share Repurchases, Date [Domain] Thereafter Finance Lease, Liability, to be Paid, after Year Five Terminated amount Derivative, Terminated Amount Derivative, Terminated Amount Award Timing Disclosures [Line Items] Service cost Defined Benefit Plan, Service Cost Weighted-average fair value of each purchase right under the ESPP (in USD per share) Aggregate Cost Of Discount Off Market Value For Shares Available Under Employee Stock Purchase Plan This element represents the value of the discount applied to the market value for shares available to participating employees under the employee stock purchase plan. Renewal term (in years) Lessee, Operating Lease, Renewal Term COMMON STOCK Equity [Text Block] State Deferred State and Local Income Tax Expense (Benefit) NET INCOME NET INCOME Net income Net Income (Loss) Attributable to Parent 737 MAX 7 B737-7Max [Member] B7737-7Max Other Other Accrued Liabilities, Current Fuel hedging and receivables Hedging Assets, Current Schedule of Income Tax Provision Reconciliation To Federal Income Tax Statutory Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Vesting periods for plans (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Repurchase of common stock Repurchase of common stock Payments for Repurchase of Common Stock Adoption Date Trading Arrangement Adoption Date Base Rate Base Rate [Member] Prepaid insurance Deferred Tax Liabilities, Prepaid Expenses Reinsurance receivable and losses recoverable Reinsurance Receivable And Losses Recoverable, Current Reinsurance Receivable And Losses Recoverable, Current Term of lease contract (in years) Lessee, Operating Lease, Term of Contract Customer [Axis] Customer [Axis] OPERATING INCOME Operating Income (Loss) Line of Credit Line of Credit [Member] Schedule of Offsetting Liabilities Offsetting Liabilities [Table Text Block] Stock Plans Compensation Related Costs, Policy [Policy Text Block] Retained earnings Retained Earnings (Accumulated Deficit) Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Other, net Proceeds From (Payments For) Other Investing Activities Proceeds From (Payments For) Other Investing Activities Passenger Passenger [Member] Fuel derivatives Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Other Deferred Tax Liabilities, Other Retirement Plan Type [Axis] Retirement Plan Type [Axis] Other (gains) losses, net Other Nonoperating Income (Expense) Statement [Table] Statement of Stockholder's Equity [Table] Statement [Table] Actual gain/(loss) on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Total deferred Deferred Income Tax Expense (Benefit) Adjustments to reconcile net income to cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] CASH FLOWS FROM FINANCING ACTIVITIES: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Proceeds from derivative instrument Proceeds from Derivative Instrument, Financing Activities Variable Rate [Domain] Variable Rate [Domain] Total Air traffic liability Air traffic liability - beginning balance Air traffic liability - ending balance Contract with Customer, Liability Finance Finance Lease, Liability, Noncurrent All Adjustments to Compensation All Adjustments to Compensation [Member] Amendment Flag Amendment Flag Postretirement Benefits Other Postretirement Benefits Plan [Member] Treasury stock, at cost: 372,530,238 and 294,797,959 shares in 2025 and 2024, respectively Treasury Stock, Common, Value Termination Date Trading Arrangement Termination Date Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Share-Based Payment Arrangement, Tranche Three Share-Based Payment Arrangement, Tranche Three [Member] Operating leases (as a percent) Operating Lease, Weighted Average Discount Rate, Percent Weighted-average shares outstanding, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Schedule of Earnings per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Share Repurchase Program [Table] Share Repurchase Program [Table] Number of aircraft orders exercised Long-Term Purchase Commitment, Quantity Exercised Long-Term Purchase Commitment, Quantity Exercised Debt Disclosure [Abstract] Debt Disclosure [Abstract] NON-OPERATING EXPENSES (INCOME): Nonoperating Income (Expense) [Abstract] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Treasury bills Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value Scenario [Domain] Scenario [Domain] OPERATING EXPENSES: Costs and Expenses [Abstract] Reclassification to earnings, deferred tax impact Reclassification from AOCI, Current Period, Tax Weighted average price of non-option equity instruments granted (in USD per share) Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Weighted Average Price Weighted average price of non-option equity instruments granted. Cash dividends Dividends, Cash Restructuring and Related Activities [Abstract] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Share based compensation arrangement by share based payment award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Accrued employee benefits Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits 3.00% Notes 3.00 Senior Notes Due 2026 [Member] 3.00 Senior Notes Due 2026 Taxes receivable Income Taxes Receivable, Current Next 5 yrs thereafter Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years Effect of cross-border tax laws Effective Income Tax Rate Reconciliation, Cross-Border Tax Effect, Amount Credit outstanding Line of Credit Facility, Fair Value of Amount Outstanding Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Operating cash flows for finance leases Finance Lease, Interest Payment on Liability Payments of cash dividends Payments of Dividends Litigation settlement, amount awarded to other party Litigation Settlement, Amount Awarded to Other Party Gross amounts of recognized liabilities Derivative Asset, Subject to Master Netting Arrangement, Liability Offset Insider Trading Arrangements [Line Items] Other Product and Service, Other [Member] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis Unobservable Input Reconciliation Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Table Text Block] This element represents, for the fair value measurement of assets and liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating gains or losses included in earnings (or changes in net assets) (2) purchases, sales, issuances, and settlements (net); and (3) transfers in and out of Level 3. 2030 Finance Lease, Liability, to be Paid, Year Five Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Advances and deposits Contract With Customer, Liability, Advances And Deposits, Current Contract With Customer, Liability, Advances And Deposits, Current Principal amount of debt repurchased Debt Instrument, Repurchased Face Amount Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Offsetting Assets Offsetting Assets [Line Items] Total lease assets Lease Right Of Use Asset Lease Right Of Use Asset Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract] Amounts deferred associated with points awarded Contract With Customer Liability, Air Traffic Liability, Loyalty Program, Awarded Points Contract With Customer Liability, Air Traffic Liability, Loyalty Program, Awarded Points Variable Rate [Axis] Variable Rate [Axis] Schedule of Share-based Compensation, Restricted Stock Units Award Activity Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Auditor Information [Abstract] Auditor Information Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Number of aircraft sales Long-Term Purchase Commitment, Aircraft Sales Long-Term Purchase Commitment, Aircraft Sales Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Consolidated Balance Sheet liability Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Minimum percentage of cost estimated residual value (as a percent) Property Plant And Equipment Percentage Cost To Residual Value Minimum The minimum percentage of cost used to determine the residual value of long lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land and improvements, buildings, and production equipment. Collateral deposits Collateral Already Posted, Aggregate Fair Value