Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Trading Arrangement: Trading Arrangement [Axis] Delivery [Domain] Delivery [Domain] Delivery [Domain] Number of aircraft options exercised Long-Term Purchase Commitment, Quantity Exercised Long-Term Purchase Commitment, Quantity Exercised Other, net Proceeds From (Payments For) Other Investing Activities Proceeds From (Payments For) Other Investing Activities Title of 12(b) Security Title of 12(b) Security Subsequent Event Subsequent Event [Member] Net income attributable to common stockholders, Diluted Net Income (Loss) Available to Common Stockholders, Diluted Document Fiscal Year Focus Document Fiscal Year Focus 1.0 Payroll Support Program Loan due 2031 1.0 Payroll Support Program Loan due 2031 [Member] 1.0 Payroll Support Program Loan due 2031 Adjustment to Compensation, Amount Adjustment to Compensation Amount Customer [Axis] Customer [Axis] Credit Agreement Credit Agreement [Member] Credit Agreement Common stock Common Stock, Value, Issued Issuance of common and treasury stock pursuant to Employee stock plans Stock Issued During Period, Value, Employee Stock Plans Aggregate change in value for stock issued during the period as a result of employee stock plans 2028 Number Of Aircrafts Ordered, Year Two Number Of Aircrafts Ordered, Year Two Line of Credit Line of Credit [Member] Passenger Passenger [Member] Restatement Determination Date Restatement Determination Date Derivative Instrument [Axis] Derivative Instrument [Axis] 2031 Number Of Aircrafts Ordered, Year Five Number Of Aircrafts Ordered, Year Five Changes in fair value, deferred tax impact Other Comprehensive Income (Loss) before Reclassifications, Tax Reinsurance receivable and losses recoverable Reinsurance Receivable and Losses Recoverable Reinsurance Receivable and Losses Recoverable Breakage Revenue Reversal Breakage Revenue Reversal [Member] Breakage Revenue Reversal Amendment Flag Amendment Flag Current liabilities: Liabilities, Current [Abstract] Inventories of parts and supplies, at cost Airline Related Inventory, Gross Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Change in Contract With Customer, Liability [Roll Forward] Change in Contract With Customer, Liability [Roll Forward] Change in Contract With Customer, Liability 2031 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Five 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). 1.250 Convertible Senior Notes 1.250 Convertible Senior Notes due 2025 [Member] 1.250 Convertible Senior Notes due 2025 7.375% Debentures Debentures due 2027 [Member] Debentures due 2027 Deferred income taxes Increase (Decrease) in Deferred Income Taxes Other payable Accounts Payable, Other, Current Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Entity Address, State or Province Entity Address, State or Province Credit card receivables Credit Card Receivables Third party services Accrued Third Party Services Accrued Third Party Services PEO Total Compensation Amount PEO Total Compensation Amount Floor percentage Debt Instrument, Interest Rate, Floor Percentage Debt Instrument, Interest Rate, Floor Percentage Amounts reclassified from AOCI Reclassification out of Accumulated Other Comprehensive Income [Member] Intangible assets, net Intangible Asset, Excluding Goodwill, after Accumulated Amortization Basic (in shares) Weighted-average shares outstanding, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Total current liabilities Liabilities, Current Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Entity Address, City or Town Entity Address, City or Town Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Assets constructed for others Assets Constructed For Others The aggregate costs related to airport construction projects recorded as an asset. Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Net income attributable to common stockholders, Basic Net Income (Loss) Available to Common Stockholders, Basic Accounts and other receivables Accounts and other receivables Accounts and Other Receivables, Net, Current Aircraft Type [Axis] Aircraft Type [Axis] Proceeds from Employee stock plans Proceeds from Stock Plans Significant other observable inputs (Level 2) Level 2 Fair Value, Inputs, Level 2 [Member] NON-OPERATING EXPENSES (INCOME): Nonoperating Income (Expense) [Abstract] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Effect of Change in Accounting Estimate, Type [Domain] Effect of Change in Accounting Estimate, Type [Domain] Schedule of 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Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Document Period End Date Document Period End Date 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] Net cash used in investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Advances and deposits Contract With Customer, Liability, Advances And Deposits, Current Contract With Customer, Liability, Advances And Deposits, Current Amended Credit Agreement Amended Credit Agreement [Member] Amended Credit Agreement Face amount of debt Debt Instrument, Face Amount OPERATING EXPENSES: Costs and Expenses [Abstract] Security Exchange Name Security Exchange Name Treasury stock, at cost Treasury Stock, Common, Value Schedule of Contractual Purchase Commitments Long-Term Purchase Commitment [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income (Loss) [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] 2028 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Two Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Current operating lease liabilities Operating Lease, Liability, Current Interest Interest Payable, Current Operating Segments and Related Disclosures Segment Reporting, Policy [Policy Text Block] Current period sales Contract With Customer, Liability, Additions Contract With Customer, Liability, Additions NET INCOME PER SHARE Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Earnings Per Share [Abstract] Earnings Per Share [Abstract] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Trading Symbol Trading Symbol Number of aircraft deliveries Long-Term Purchase Commitment, Aircraft Deliveries Long-Term Purchase Commitment, Aircraft Deliveries 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] Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Company Selected Measure Name Company Selected Measure Name Reclassification to earnings Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent 2029 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Three Defined benefit plan items Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Credit Facility [Domain] Credit Facility [Domain] Depreciation and amortization Depreciation and amortization expense Depreciation, Depletion and Amortization, Nonproduction CASH FLOWS FROM OPERATING ACTIVITIES: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Other Other Sundry Liabilities, Noncurrent Other Other Receivables, Net, Current Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Diluted (in shares) Weighted-average shares outstanding, diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Schedule of Change in Accounting Estimate Schedule of Change in Accounting Estimate [Table Text Block] Entity Emerging Growth Company Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text 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Credits Contract With Customer, Liability, Non-expiring Flight Credits Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Award Timing Predetermined Award Timing Predetermined [Flag] Cash collateral provided to derivative counterparties Increase (Decrease) Cash Collateral from Counterparties Treasury stock Treasury Stock, Common [Member] Schedule of Components of Net Income and Comprehensive Income Comprehensive Income (Loss) [Table Text Block] 2024 Contractual Deliveries 2024 Contractual Deliveries [Member] 2024 Contractual Deliveries Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Share-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Quoted prices in active markets for identical assets (Level 1) Fair Value, Inputs, Level 1 [Member] Other Other Assets, Miscellaneous B-7 B-7 [Member] B-7 Aircraft [Domain] Aircraft [Domain] Organization, Consolidation and Presentation of Financial Statements [Abstract] Fair Value Measurements Fair Value of Financial Instruments, Policy [Policy Text Block] Number of aircrafts to be delivered Number Of Aircrafts To Be Delivered Number Of Aircrafts To Be Delivered Flight credits (as a percent) Residual Travel Funds Residual Travel Funds Dilutive effect of restricted stock units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements 4.375% Notes 4.375 Notes due 2028 [Member] 4.375 Notes due 2028 All Executive Categories All Executive Categories [Member] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Scenario [Domain] Scenario [Domain] Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Derivative Liability, Statement of Financial Position [Extensible Enumeration] Derivative Liability, Statement of Financial Position [Extensible Enumeration] Non-expiring flight credits issued Contract With Customer, Non-expiring Flight Credits Issued Contract With Customer, Non-expiring Flight Credits Issued Schedule of Earnings per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Current maturities of long-term debt Long-Term Debt and Lease Obligation, Current Expiration Date Trading Arrangement Expiration Date Hedging Relationship [Axis] Hedging Relationship [Axis] Schedule of Disaggregation of Passenger Revenue Disaggregation of Revenue [Table Text Block] DENOMINATOR: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Income Statement Location [Axis] Location, Statement of Income, Balance [Axis] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure 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] Percentage of flight credits not redeemed Contract With Customer, Liability, Non-expiring Flight Credits, Percentage Not Redeemed Contract With Customer, Liability, Non-expiring Flight Credits, Percentage Not Redeemed Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivative [Table] Derivative [Table] Delivery [Axis] Delivery [Axis] Delivery WEIGHTED AVERAGE SHARES OUTSTANDING NET INCOME PER SHARE: Earnings Per Share Reconciliation [Abstract] Antidilutive Security, Excluded EPS Calculation [Table] Antidilutive Security, Excluded EPS Calculation [Table] Accounts and other receivables Increase (Decrease) in Accounts and Other Receivables Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Number of payroll support programs Number Of Payroll Support Programs Number Of Payroll Support Programs Flight equipment Airline, Property, Plant, and Equipment, Flight Equipment, before Accumulated Depreciation Health Accrued Employee Benefits, Current Passenger non-loyalty Passenger Revenue, Non-Loyalty [Member] Passenger Revenue, Non-Loyalty [Member] Exercise Price Award Exercise Price CASH FLOWS FROM INVESTING ACTIVITIES: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Term Loan Credit Agreement Term Loan Credit Agreement [Member] Term Loan Credit Agreement Contractual Year Axis [Axis] Contractual Year [Axis] Contractual Year 3.450% Notes 3.45 Unsecured Senior Notes due 2027 [Member] 3.45 Unsecured Senior Notes due 2027 Document Quarterly Report Document Quarterly Report Proceeds from sale-leaseback transactions Sale Leaseback Cash Proceeds Investing Sale Leaseback Cash Proceeds Investing 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] Interest Rate Swap Interest Rate Swap [Member] B-8 B-8 [Member] B-8 FINANCING ACTIVITIES Debt Disclosure [Text Block] Scenario [Axis] Scenario [Axis] Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Residual Values Residual Value, Policy [Policy Text Block] Residual Value, Policy Other deferred compensation Other Deferred Compensation Arrangements, Liability, Classified, Noncurrent Equity Component [Domain] Equity Component [Domain] Firm Orders Long-Term Commitment (Excluding Unconditional Purchase Obligation) [Abstract] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Secured Debt Secured Debt [Member] Accounts payable trade Accounts Payable, Trade, Current 2025 Contractual Deliveries 2025 Contractual Deliveries [Member] 2025 Contractual Deliveries 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). Schedule of Accounts Payable Schedule Of Accounts Payable [Table Text Block] Tabular disclosure of the components of accounts payable. Adoption Date Trading Arrangement Adoption Date Interest rate stated in the debt agreement (as a percent) Debt Instrument, Interest Rate, Stated Percentage Total stockholders' equity Balance at beginning of period Balance at end of period Equity, Attributable to Parent Total non-operating expenses (income) Nonoperating Income (Expense) Accordion feature incremental commitments Debt Instrument, Face Amount, Accordion Feature, Incremental Commitments, Amount Debt Instrument, Face Amount, Accordion Feature, Incremental Commitments, Amount ASSETS Assets Assets [Abstract] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount MAX MAX [Member] MAX Workers' compensation Workers' Compensation Liability, Current Accounting Policies [Abstract] Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Accordion feature incremental commitments Debt Instrument, Face Amount, Accordion Feature, Additional Incremental Commitments, Amount Debt Instrument, Face Amount, Accordion Feature, Additional Incremental Commitments, Amount Passenger Passenger Customers [Member] Passenger Customers Insider Trading Policies and Procedures [Line Items] Other, net Proceeds from (Payment for) Other Financing Activity Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Early repayments of loan Repayments of Debt B737-8 -8 Firm Orders B-737-8MAX [Member] B737-8MAX COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Potentially dilutive amounts excluded from calculations (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 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 Proceeds from sales of short-term and other investments Proceeds from Sale of Short-Term Investments Entity Central Index Key Entity Central Index Key Less allowance for depreciation and amortization Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization Capital in excess of par value Additional Paid in Capital, Common Stock All Adjustments to Compensation All Adjustments to Compensation [Member] Other, net Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Other Item 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] Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Income Statement [Abstract] Income Statement [Abstract] Stockholders' equity: Equity, Attributable to Parent [Abstract] Document Transition Report Document Transition Report Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Designated as Hedging Instrument Designated as Hedging Instrument [Member] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Capitalized interest Interest Costs Capitalized Adjustment City Area Code City Area Code Variable Rate [Domain] Variable Rate [Domain] B-737-700 B-737-700 [Member] 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 Accumulated other comprehensive income (loss) AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] Convertible debt Convertible Debt Securities [Member] 2027 Number Of Aircrafts Ordered, Year One Number Of Aircrafts Ordered, Year One Payments of cash dividends Payments of Dividends Name Forgone Recovery, Individual Name Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Statement [Line Items] Statement [Line Items] Total assets Assets Convertible Debt Convertible Debt [Member] Revenue from current period sales Contract With Customer, Liability, Revenue Recognized, Current Period Contract With Customer, Liability, Revenue Recognized, Current Period New Accounting Pronouncements and Changes in Accounting Principles [Abstract] Accounting Standards Update and Change in Accounting Principle [Abstract] Interest expense Interest expense Interest Expense, Nonoperating 2029 Number Of Aircrafts Ordered, Year Three Number Of Aircrafts Ordered, Year Three Changes in fair value OCI, before Reclassifications, Net of Tax, Attributable to Parent Other assets Increase (Decrease) in Other Operating Assets PEO PEO [Member] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Number of aircraft deliveries converted Long-Term Purchase Commitment, Aircraft Deliveries Converted Long-Term Purchase Commitment, Aircraft Deliveries Converted Other Other Customer [Member] Cash equivalents Cash Equivalents [Member] Other noncurrent liabilities Other noncurrent liabilities Other Liabilities, Noncurrent Goodwill Goodwill Year 2028 Year 2028 [Member] Year 2028 Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Profit-sharing and savings plans Deferred Compensation Cash-Based Arrangements, Liability, Current Revenue from amounts included in contract liability opening balances Contract with Customer, Liability, Revenue Recognized Subsequent Event Type [Domain] Subsequent Event Type [Domain] Ticket taxes and fees Taxes Payable, Current Retained earnings Retained Earnings [Member] Noncurrent operating lease liabilities Operating Lease, Liability, Noncurrent Revolving Credit Facility Revolving Credit Facility [Member] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Award Timing Disclosures [Line Items] Schedule of Fair value, by Balance Sheet Grouping Fair Value, by Balance Sheet Grouping [Table Text Block] NET INCOME PER SHARE, DILUTED (in dollars per share) Net income per diluted share (in dollars per share) Diluted (in dollars per share) Earnings Per Share, Diluted Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Entity Current Reporting Status Entity Current Reporting Status Other Other Contract [Member] Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount Cash Flow Hedging Cash Flow Hedging [Member] 2024 and 2025 Contractual Deliveries 2024 and 2025 Contractual Deliveries [Member] 2024 and 2025 Contractual Deliveries B737-7 -7 Firm Orders B737-7Max [Member] B7737-7Max Deposits on flight equipment purchase contracts Deposits on Flight Equipment Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Total number of aircrafts ordered Number Of Aircrafts Ordered Number Of Aircrafts Ordered Long-term Purchase Commitment [Line Items] Long-Term Purchase Commitment [Line Items] Reclassification to earnings, deferred tax impact Reclassification from AOCI, Current Period, Tax CASH FLOWS FROM FINANCING ACTIVITIES: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Total operating revenues Total passenger revenues Total other revenues Revenue from Contract with Customer, Excluding Assessed Tax Property and equipment, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Landing fees and airport rentals Airline, Landing Fee and Other Rent Expenses Proceeds from sale and leaseback transactions Proceeds from Sale and Leaseback Transaction Proceeds from Sale and Leaseback Transaction Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Purchases of short-term investments Payments to Acquire Short-Term Investments REVENUE Revenue from Contract with Customer [Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block] Year 2024 and 2025 Year 2024 and 2025 [Member] Year 2024 and 2025 Maintenance materials and repairs Airline, Maintenance and Repair Expenses Other Product and Service, Other - Other Miscellaneous [Member] Product and Service, Other - Other Miscellaneous 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 Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] OPERATING INCOME Operating Income (Loss) Property and income taxes Accrual for Property And Income Taxes Accrual for Property And Income Taxes Current Fiscal Year End Date Current Fiscal Year End Date Proceeds from issuance of long-term debt Proceeds from Issuance of Debt Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount 2.625% Notes 2.625 Unsecured Senior Notes Due 2030 [Member] 2.625 Unsecured Senior Notes Due 2030 Unrecorded Unconditional Purchase Obligation [Table] Unrecorded Unconditional Purchase Obligation [Table] 2026 Contractual Deliveries 2026 Contractual Deliveries [Member] 2026 Contractual Deliveries Derivative [Line Items] Derivative [Line Items] Estimated fair value Notes Payable, Fair Value Disclosure Total Unrecorded Unconditional Purchase Obligation 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] Earnings Per Share, Diluted, by Common Class, Including Two-Class Method [Table] Earnings Per Share, Diluted, by Common Class, Including Two-Class Method [Table] Cash dividends, per share (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] B-737-800 B-737-800 [Member] Reclassification from AOCI from termination of fuel hedging contracts (Gain) loss recognized in AOCI on derivatives, net of tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Impairment of long-lived assets Asset, Impairment Loss Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Measure: Measure [Axis] Deferred co-brand revenue Contract with Customer Liability, Loyalty Co-Branding, Noncurrent Contract with Customer Liability, Loyalty Co-Branding, Noncurrent Deferred tax impact, beginning balance Deferred tax impact, ending balance AOCI Tax, Attributable to Parent COMPREHENSIVE INCOME Comprehensive Income (Loss) Note [Text Block] Equity Components [Axis] Equity Components [Axis] Other operating expenses Other operating expenses Other Cost and Expense, Operating Product and Service [Domain] Product and Service [Domain] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Variable Rate [Axis] Variable Rate [Axis] Deferred income taxes Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Entity Small Business Entity Small Business Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] COMPREHENSIVE INCOME Comprehensive income (loss) COMPREHENSIVE INCOME Comprehensive Income (Loss), Net of Tax, Attributable to Parent Termination Date Trading Arrangement Termination Date Reinsurance payable and losses payable Reinsurance Payable and Losses Payable Reinsurance Payable and Losses Payable Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Other assets Other assets Other Assets, Noncurrent Document Type Document Type Principal amount of debt repurchased Debt Instrument, Repurchased Face Amount 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] Accrued liabilities Accrued liabilities Accrued Liabilities, Current Fair Value as of Grant Date Award Grant Date Fair Value Change in Accounting Estimate [Table] Change in Accounting Estimate [Table] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Number of aircraft retirements Long-Term Purchase Commitment, Aircraft Retirements Long-Term Purchase Commitment, Aircraft Retirements Total operating expenses Operating Costs and Expenses Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Unrecorded Unconditional Purchase Obligation [Line Items] Unrecorded Unconditional Purchase Obligation [Line Items] Air traffic liability - noncurrent Contract with Customer, Liability, Noncurrent SUPPLEMENTAL FINANCIAL INFORMATION Additional Financial Information Disclosure [Text Block] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name INCOME BEFORE INCOME TAXES Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Schedule of Other Noncurrent Liabilities Other Noncurrent Liabilities [Table Text Block] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Property and equipment, at cost Property, Plant, and Equipment, before Accumulated Depreciation, Depletion, and Amortization Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Year 2026 Year 2026 [Member] Year 2026 Reclassification out of Accumulated Other Comprehensive Income (Loss) [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Long-term Purchase Commitment [Table] Long-Term Purchase Commitment [Table] LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] 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] All Award Types Award Type [Domain] 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 Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] CASH PAYMENTS FOR: Supplemental Cash Flow Information [Abstract] Shares acquired in repurchase (in shares) Treasury Stock, Shares, Acquired PEO Name PEO Name Aircraft maintenance Accrued Aircraft Maintenance, Current Accrued Aircraft Maintenance, Current Total Air traffic liability Beginning balance Ending balance Contract with Customer, Liability Fuel derivatives Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Passenger loyalty - air transportation Passenger Loyalty, Air Transportation [Member] Passenger Loyalty, Air Transportation [Member] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Unrealized loss on fuel derivative instruments, net of deferred taxes Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Repurchase of common stock Treasury Stock, Value, Acquired, Cost Method Air traffic liability - loyalty program Beginning balance Ending balance Contract With Customer Liability, Air Traffic Liability, Loyalty Program Contract With Customer Liability, Air Traffic Liability, Loyalty Program 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 Other Other Accrued Liabilities, Current Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Base Rate Base Rate [Member] Term Loan Credit Facility Term Loan Credit Facility [Member] Term Loan Credit Facility Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Freight Cargo and Freight [Member] Schedule of Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] 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] Debt Instrument [Axis] Debt Instrument [Axis] Service Life Service Life [Member] Cash dividends Dividends, Cash Salaries, wages, and benefits Labor and Related Expense Customer [Domain] Customer [Domain] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] 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] NET INCOME PER SHARE, BASIC (in dollars per share) Net income per basic share (in dollars per share) Basic (in dollars per share) Earnings Per Share, Basic Prepaid maintenance Prepaid Maintenance Prepaid Maintenance Repurchase of common stock Payments for Repurchase of Common Stock Air traffic liability Contract with Customer, Liability, Current Total current assets Assets, Current Insider Trading Arrangements [Line Items] Time deposits Bank Time Deposits [Member] Award Type Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Trade receivables Accounts Receivable, after Allowance for Credit Loss, Current Retained earnings Retained Earnings (Accumulated Deficit) Fuel derivative contracts Fuel derivatives Commodity Contract [Member] Product and Service [Axis] Product and Service [Axis] Equity Securities Equity Securities, FV-NI 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] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common stock Common Stock [Member] Revenue recognized from points redeemed Contract With Customer, Liability, Loyalty Program, Revenue Recognized Contract With Customer, Liability, Loyalty Program, Revenue Recognized Deferred supplier credits Supplier Finance Program, Obligation, Current Effect of Change in Accounting Estimate, Type [Axis] Effect of Change in Accounting Estimate, Type [Axis] Reclassification out of Accumulated Other Comprehensive Income (Loss) [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Capital commitments for 2028 2027 Unrecorded Unconditional Purchase Obligation, to be Paid, Year One Derivative Contract Type [Domain] Derivative Contract [Domain] Equity Awards Adjustments Equity Awards Adjustments [Member] Schedule of Capital Commitments Unrecorded Unconditional Purchase Obligations Disclosure [Table Text Block] Hedging Relationship [Domain] Hedging Relationship [Domain] Total liabilities and stockholders' equity Liabilities and Equity Salaries, withholdings, and payroll taxes Accrued Salaries, Current Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Employee Stock Option Share-Based Payment Arrangement, Option [Member] Other liabilities Increase (Decrease) in Other Operating Liabilities Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Schedule of Accounts and Other Receivables Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Tabular List, Table Tabular List [Table Text Block] Contractual Year [Domain] Contractual Year [Domain] Contractual Year [Domain] Loyalty partners Loyalty Partners, Current Loyalty Partners, Current Gain on sale-leaseback transactions Gain on sale-leaseback transactions Sale and Leaseback Transaction, Gain (Loss), Net Equity securities Equity Securities, FV-NI, Noncurrent Other gains, net Other Nonoperating Income (Expense) Taxes receivable Income Taxes Receivable, Current Name Awards Close in Time to MNPI Disclosures, Individual Name 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] 3.000% Notes Unsecured Senior Notes Due 2026 [Member] Unsecured Senior Notes Due 2026 Property and equipment, at cost: Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization [Abstract] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Bonus pay Accrued Bonuses, Current Adjustment to Compensation: Adjustment to Compensation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Interest, net of amount capitalized Interest Paid, Excluding Capitalized Interest, Operating Activity Capital expenditures Payments to Acquire Productive Assets Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Hedging Designation [Axis] Hedging Designation [Axis] Other deferred taxes Other Comprehensive Income, Other, Tax Other Comprehensive Income, Other, Tax Other Accumulated Other Adjustments Attributable to Parent [Member] Accumulated Other Adjustments Attributable to Parent Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total assets Assets, Fair Value Disclosure Long-term debt less current maturities Long-Term Debt and Lease Obligation Name Measure Name Accounts payable Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Other comprehensive loss in AOCI related to termination of fuel hedging contracts Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax Capital in excess of par value Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category 2030 Number Of Aircrafts Ordered, Year Four Number Of Aircrafts Ordered, Year Four 5.125% Notes 5.125 Notes due 2027 [Member] 5.125 Notes due 2027 Name Trading Arrangement, Individual Name Aircraft Aircraft [Member] Aircraft Cash and cash equivalents Cash and Cash Equivalent BASIS OF PRESENTATION Basis of Accounting [Text Block] Company Selected Measure Amount Company Selected Measure Amount 2030 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Four Secured Overnight Financing Rate (SOFR) Secured Overnight Financing Rate (SOFR) [Member] Flight and ground equipment acquired or modified under finance leases Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Vacation pay Accrued Vacation, Current Current assets: Assets, Current [Abstract] 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 Total derivatives designated as hedges Derivative Liability Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Right-of-use assets acquired or modified under operating leases Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Credit outstanding Line of Credit Facility, Fair Value of Amount Outstanding PROVISION FOR INCOME TAXES Tax expense Income Tax Expense (Benefit) Award Timing Method Award Timing Method [Text Block] 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 Other Product and Service, Other [Member] Forecast Forecast [Member] Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] NEW ACCOUNTING PRONOUNCEMENTS Accounting Standards Update and Change in Accounting Principle [Text Block] Aircraft fuel and related taxes Aircraft fuel and related taxes Fuel Costs AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] NET INCOME Net income NET INCOME Net of tax Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Proceeds from sale of property and equipment Proceeds from Sale of Property, Plant, and Equipment Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Interest rate derivatives (see Note 3) Interest Rate Derivative Liabilities, at Fair Value Schedule of Rollforward of the Amounts Included in AOCI, Net of Taxes Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Interest income Investment Income, Interest Schedule of Rollforward of Air Traffic Liability Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Number of claims alleged in litigation case Number Of Claims Alleged In Litigation Case Number Of Claims Alleged In Litigation Case Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Schedule of Other Assets Schedule of Other Assets [Table Text Block] OPERATING REVENUES: Revenues [Abstract] Remainder of 2026 Unrecorded Unconditional Purchase Obligation, to be Paid, Remainder of Fiscal Year 2026 Number Of Aircrafts Ordered, Remainder Of Fiscal Year Number Of Aircrafts Ordered, Remainder Of Fiscal Year Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] NUMERATOR: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract]