Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Virgin America Inc. [Member] Virgin America Inc. [Member] Virgin America Inc. [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Revenue Business Acquisition, Pro Forma Revenue Net Income Business Acquisition, Pro Forma Net Income (Loss) Cash, Cash Equivalents, and Short-term Investments [Abstract] Schedule of Cash, Cash Equivalents and Short-term Investments [Table Text Block] Cash, Cash Equivalents and Investments [Table Text Block] Schedule of Realized Gain (Loss) [Table Text Block] Schedule of Realized Gain (Loss) [Table Text Block] Schedule of Debt Investment Maturities [Table Text Block] Investments Classified by Contractual Maturity Date [Table Text Block] Debt Disclosure [Abstract] LONG-TERM DEBT Long-term Debt [Text Block] Compensation and Retirement Disclosure [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Qualified Defined Benefit [Member] Pension Plan [Member] Postretirement Medical Benefits [Member] Other Postretirement Benefit Plan [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on assets Defined Benefit Plan, Expected Return on Plan Assets Amortization of prior service cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Recognized actuarial loss Defined Benefit Plan, Amortization of Gains (Losses) Settlement expense (special item) Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements Net pension expense Defined Benefit Plan, Net Periodic Benefit Cost Plan settlement Defined Benefit Plan, Settlements, Benefit Obligation SPECIAL ITEMS [Abstract] SPECIAL ITEMS [Abstract] Unusual or Infrequent Items Disclosure [Text Block] Unusual or Infrequent Items, or Both, Disclosure [Text Block] Commitments and Contingencies Disclosure [Abstract] Schedule of Future Minimum Rental Payments for Operating Leases and Unrecorded Unconditional Purchase Obligtaions [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases and Unrecorded Unconditional Purchase Obligations [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases and Unrecorded Unconditional Purchase Obligtaions [Table Text Block] Benefit obligation Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Beginning of year Defined Benefit Plan, Benefit Obligation Plan settlement Actuarial (gain) loss Defined Benefit Plan, Actuarial Gain (Loss) Benefits paid Defined Benefit Plan, Benefits Paid End of year Plan assets at fair value Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Beginning of year Defined Benefit Plan, Fair Value of Plan Assets Actual return on plan assets Defined Benefit Plan, Actual Return on Plan Assets Employer contributions Defined Benefit Plan, Contributions by Employer Plan settlement Defined Benefit Plan, Settlements, Plan Assets End of year Funded status (unfunded) Defined Benefit Plan, Funded Status of Plan Percent funded Defined Benefit Plan, Funded Percentage Accumulated benefit obligation Defined Benefit Plan, Accumulated Benefit Obligation Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Air Group Adjusted [Member] Air Group Adjusted [Member] Air Group Adjusted [Member] Alaska Airlines [Member] Alaska Airlines [Member] Alaska Airlines [Member] Alaska Mainline [Member] Alaska Mainline [Member] Alaska Mainline [Member] Alaska Regional [Member] Alaska Regional [Member] Alaska Regional [Member] Horizon [Member] Horizon [Member] Horizon Segment [Member] Parent [Member] Segment Reconciling Items [Member] Intersegment Eliminations Intersegment Eliminations [Member] Special Charges [Member] Special Charges [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Operating revenues Revenues [Abstract] Passenger, Mainline Passenger Revenue, Mainline Passenger, Regional Passenger Revenue, Regional Total passenger revenue Passenger Revenue CPA revenues Revenues Freight and mail Cargo and Freight Revenue Other Net and Special Revenue Other Net and Special Revenue Other Net and Special Revenue Total Operating Revenues Revenue, Net Operating expenses Operating Expenses [Abstract] Operating expenses, excluding fuel Operating Expenses, Excluding Fuel Operating Expenses, Excluding Fuel Special items—merger-related costs and other Business Combination, Acquisition Related Costs Economic fuel Fuel Costs Total Operating Expenses Operating Expenses Nonoperating Income (Expense) Nonoperating Income (Expense) [Abstract] Interest income Investment Income, Interest Interest expense Interest Expense Other Other Nonoperating Income Expense Other Other Nonoperating Income Expense Other Nonoperating Income (Expense) Total Nonoperating Income (Expense) Income (loss) before income tax Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Depreciation Depreciation, Depletion and Amortization Capital expenditures Payments to Acquire Property, Plant, and Equipment Total assets Assets Equity [Abstract] Unrealized gain on marketable securities considered available-for-sale Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Related to employee benefit plans Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax Related to interest rate derivatives Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Schedule of Fair Value of Consideration Transferred Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Recognized Identified Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Business Acquisition, Pro Forma Information Business Acquisition, Pro Forma Information [Table Text Block] Fair Value Disclosures [Abstract] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative [Table] Derivative [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Gains (losses) recognized in Interest Expense [Member] Interest Expense [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Secured Debt [Member] Secured Debt [Member] Hedging Designation [Axis] Hedging Designation [Domain] Not Designated as Hedging Instrument [Member] Derivative Instruments Designated as Hedges [Member] Designated as Hedging Instrument [Member] Derivative Instrument [Axis] Derivative Contract [Domain] Fuel hedge contracts [Member] Commodity Contract [Member] Interest rate swaps agreements [Member] Interest Rate Swap [Member] Aircraft Type [Axis] Aircraft Type [Axis] Aircraft Type [Domain] Aircraft [Domain] B737-800 [Member] B-737-800 [Member] Derivative [Line Items] Derivative [Line Items] Net cash received (paid) to for new positions and settlements Payments for (Proceeds from) Hedge, Investing Activities Fuel hedge contracts outstanding (in gallons) Derivative, Nonmonetary Notional Amount Capital Leased Assets, Number of B737-800 Aircraft Capital Leased Assets, Number of Units Number of interest rate swap agreements Derivative, Number of Instruments Held Derivative, Notional Amount Derivative, Notional Amount Number of shares of Virgin America common stock issued and outstanding Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Multiplied by cash consideration for each share of common stock per the merger agreement Business Acquisition, Share Price Cash consideration paid for common stock issued and outstanding Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Accelerated and vested equity awards attributable to pre-acquisition service Business Combination, Consideration Transferred, Equity Awards Pre-acquisition Service Business Combination, Consideration Transferred, Equity Awards Pre-acquisition Service Total Purchase Price Business Combination, Consideration Transferred Accounting Policies [Abstract] GENERAL AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Significant Accounting Policies [Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Fixed-rate notes payable due through 2028 Fixed rate notes payable due through 2024 [Member] Fixed rate notes payable due through 2024 Variable-rate notes payable due through 2028 Variable rate notes payable due through 2024 [Member] Variable rate notes payable due through 2024 [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Long-term Debt Long-term Debt Less debt issuance costs Debt Issuance Costs, Net Less current portion Long-term Debt, Current Maturities Long-term debt, net of current portion Long-term Debt, Excluding Current Maturities Weighted-average fixed-interest rate Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate Weighted-average variable-interest rate Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate Proceeds from issuance of long-term debt, net of issuance costs Proceeds from Issuance of Debt Long-term debt payments Repayments of Long-term Debt Long-term Debt, Fiscal Year Maturity [Abstract] 2017 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2018 Long-term Debt, Maturities, Repayments of Principal in Year Two 2019 Long-term Debt, Maturities, Repayments of Principal in Year Three 2020 Long-term Debt, Maturities, Repayments of Principal in Year Four 2021 Long-term Debt, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Long-term Debt Long-term Debt, Gross Income Tax Disclosure [Abstract] Current tax expense (benefit): Components of Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Total current Current Income Tax Expense (Benefit) Deferred tax expense: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Total deferred Deferred Income Tax Expense (Benefit) Total tax expense related to income Income Tax Expense (Benefit) Property, Plant and Equipment [Table Text Block] Property, Plant and Equipment [Table Text Block] Liabilities from Mileage Plan [Table Text Block] Liabilities from Mileage Plan [Table Text Block] Liabilities from Mileage Plan Revenue from Mileage Plan [Table Text Block] Revenue from Mileage Plan [Table Text Block] Revenue from Mileage Plan Schedule of Treasury Stock by Class [Table Text Block] Class of Treasury Stock [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] 2015 $1 billion Repurchase Program [Member] 2015 1 Billion Repurchase Program [Member] 2015 1 Billion Repurchase Program [Member] 2014 $650 million Repurchase Program $650 million Repurchase Program [Domain] $650 million Repurchase Program [Domain] 2012 $250 million Repurchase Program $250 million Repurchase Program [Member] $250 million Repurchase Program Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Share repurchase program, authorized amount Stock Repurchase Program, Authorized Amount Common stock repurchase (in shares) Stock Repurchased During Period, Shares Common stock repurchase Stock Repurchased During Period, Value Fair Value, by Balance Sheet Grouping [Table Text Block] Fair Value, by Balance Sheet Grouping [Table Text Block] SHAREHOLDER'S EQUITY Stockholders' Equity Note Disclosure [Text Block] ACQUISITION OF VIRGIN AMERICA, INC. Business Combination Disclosure [Text Block] Operating Segment Information Segment Reporting Disclosure [Text Block] Excess of tax over book depreciation Deferred Tax Liabilities, Property, Plant and Equipment Deferred Tax Liabilities, Intangible Assets Deferred Tax Liabilities, Intangible Assets Other—net Deferred Tax Liabilities, Other Gross deferred tax liabilities Deferred Tax Liabilities, Gross Mileage Plan Deferred Tax Assets, Mileage Plan Deferred Tax Assets, Mileage Plan Inventory obsolescence Deferred Tax Assets, Inventory Deferred gains Deferred Tax Assets, Deferred Income Employee benefits Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits Fuel hedge contracts Deferred Tax Assets, Derivative Instruments Acquired net operating losses Deferred Tax Assets, Operating Loss Carryforwards Other—net Deferred Tax Assets, Other Gross deferred tax assets Deferred Tax Assets, Gross Valuation allowance Operating Loss Carryforwards, Valuation Allowance Net deferred tax liabilities Deferred Tax Liabilities, Net Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Federal [Member] Domestic Tax Authority [Member] State [Member] State and Local Jurisdiction [Member] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Income Tax Authority, Name [Domain] Tax Period [Axis] Tax Period [Axis] Tax Period [Domain] Tax Period [Domain] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Net operating loss Operating Loss Carryforwards Schedule Of Mileage Plan Liabilities [Table] Schedule of Mileage Plan [Table] Schedule of Mileage Plan [Table] Mileage Plan [Axis] Mileage Plan [Axis] Mileage Plan [Axis] Mileage Plan [Domain] Mileage Plan [Domain] Mileage Plan [Domain] Revenue From Mileage Plan [Member] Revenue From Mileage Plan [Member] Revenue From Mileage Plan [Member] Liabilities From Mileage Plan [Member] Liabilities From Mileage Plan [Member] Liabilities From Mileage Plan [Member] Mileage Plan [Line Items] Mileage Plan [Line Items] Mileage Plan [Line Items] Other accrued liabilities Accrued Liabilities, Current Other liabilities Other Liabilities, Noncurrent Deferred revenue Deferred Revenue Liabilities Liabilities Deferred revenue from Mileage Plan awards issued but not yet flown Deferred Revenue, Mileage Plan Awards, Issued but not Yet Flown Deferred Revenue, Mileage Plan Awards, Issued but not Yet Flown Passenger revenues Other-net revenues Other Revenue, Net Commission revenue Commission Revenue Commission Revenue Allowance for all non-surplus expendable inventories Inventory Valuation Reserves Fuel inventory Energy Related Inventory EMPLOYEE BENEFIT PLANS Pension and Other Postretirement Benefits Disclosure [Text Block] Stock Split [Table] Stock Split [Table] Stock Split [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] prestocksplit [Domain] prestocksplit [Domain] pre-stock split [Domain] Stock Split [Line Items] Stock Split [Line Items] [Line Items] for Stock Split [Table] Common stock, shares authorized Common Stock, Shares Authorized Common stock, par value Common Stock, Par or Stated Value Per Share Defined Benefit Plan by Plan Asset Categories [Axis] Defined Benefit Plan, Asset Categories [Axis] Plan Asset Categories [Domain] Plan Asset Categories [Domain] Equity funds [Member] Equity Funds [Member] Credit bond index fund [Member] Credit bond index fund [Member] Credit bond index fund Fixed Income Funds [Member] Fixed Income Funds [Member] Real Estate [Member] Real Estate [Member] Investment Geographic Region [Axis] Investment Geographic Region [Domain] U.S. UNITED STATES Non-U.S. [Member] Non United States [Member] Non United States [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Plan asset allocations Defined Benefit Plan, Actual Plan Asset Allocations Defined Benefit Plan, Assets, Target Allocations [Abstract] Equities, Range Minimum Defined Benefit Plan, Target Plan Asset Allocations Range Minimum Equities, Range Maximum Defined Benefit Plan, Target Plan Asset Allocations Range Maximum Plan Assets 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] Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table] Derivative Instruments, Gain (Loss) [Table] Hedging Relationship [Axis] Hedging Relationship [Domain] Cash Flow Hedging [Member] Derivative Instruments Not Designated as Hedges [Member] Derivative Instrument Risk [Axis] Derivative Contract Type [Domain] Income Statement and Other Comprehensive Income (Loss) Location [Domain] Gains (losses) recognized in aircraft fuel expense [Member] Aircraft Fuel Expense [Member] Aircraft Fuel Expense [Member] Gains (losses) recognized in aircraft rent [Member] Aircraft Rent [Member] Aircraft Rent [Member] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Losses recognized in income Derivative, Gain (Loss) on Derivative, Net Losses in accumulated other comprehensive loss Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Loss expected to be reclassified Price Risk Cash Flow Hedge Unrealized Gain (Loss) to be Reclassified During Next 12 Months Schedule of Segment Reporting Information, by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES Cash, Cash Equivalents, and Marketable Securities [Text Block] DERIVATIVE INSTRUMENTS Derivative Instruments and Hedging Activities Disclosure [Text Block] Boeing, 737-900ER [Member] Boeing, 737-900ER [Member] Boeing, 737-900Er [Member] Secured Debt, Aircraft Collateral [Member] Secured Debt, Aircraft Collateral [Member] Secured Debt, Aircraft Collateral [Member] Secured Debt, Aircraft Purchase Agreements [Member] Secured Debt, Aircraft Purchase Agreements [Member] Secured Debt, Aircraft Purchase Agreements [Member] Debt instrument, increase Debt Instrument, Increase (Decrease), Net Proceeds from issuance of secured debt Proceeds from Issuance of Secured Debt Secured debt, number of aircrafts securing debt financing Secured Debt, Number of Aircrafts Securing Debt Financing Secured Debt, Number of Aircrafts Securing Debt Financing Repayments of debt Repayments of Debt Disclosure of Compensation Related Costs, Share-based Payments [Abstract] STOCK-BASED COMPENSATION PLANS Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Aircraft Rent [Member] Interest Expense [Member] Hedging Designation [Axis] Hedging Designation [Domain] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Fuel Hedge Contracts, Current [Member] Fuel Hedge Contracts, Current [Member] Fuel Hedge Contracts, Current [Member] Fuel Hedge Contracts, Noncurrent [Member] Fuel Hedge Contracts, Noncurrent [Member] Fuel Hedge Contracts, Noncurrent [Member] Other Accrued Liabilities [Member] Other Accrued Liabilities [Member] Other Accrued Liabilities [Member] Other Liabilities [Member] Other Liabilities [Member] Accumulated Other Comprehensive Loss [Member] Accumulated Other Comprehensive Income (Loss), Balance Sheet Location [Member] Accumulated Other Comprehensive Income Loss, Balance Sheet Location Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Derivative Assets, Current Derivative Asset, Current Derivative Assets, Noncurrent Derivative Asset, Noncurrent Derivative Liabilities, Current Derivative Liability, Current Derivative Liabilities, Noncurrent Derivative Liability, Noncurrent Accumulated other comprehensive loss Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Benefit obligation Recognized net gain (loss) due to curtailments Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments Recognized net gain (loss) due to curtailments, sick leave subsidy Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments, Sick Leave Subsidy Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments, Sick Leave Subsidy Recognized net gain (loss) due to curtailments, special items Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments, Special Items Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments, Special Items Postretirement Health Coverage [Member] Postretirement Health Coverage [Member] Total liability net of a prefunded trust account Other Deferred Compensation Arrangements, Liability, Classified, Noncurrent Prefunded trust account Prefunded Trust Account Prefunded Trust Account Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangement by Share-based Award Type [Axis] Award Type [Axis] Award Type [Domain] Equity Award [Domain] Employee stock purchase plan [Member] Employee Stock [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] U.S. government and agency securities US Treasury and Government [Member] Foreign government bonds Foreign Government Debt Securities [Member] Asset-backed securities Asset-backed Securities, Securitized Loans and Receivables [Member] Mortgage-backed securities Collateralized Mortgage Backed Securities [Member] Corporate notes and bonds Corporate Debt Securities [Member] Municipal securities US States and Political Subdivisions Debt Securities [Member] Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value by Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Recurring [Member] Fair Value, Measurements, Recurring [Member] 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] Available-for-sale Securities, Current Available-for-sale Securities, Current Marketable securities Available-for-sale Securities Derivative instruments, assets Derivative Asset Derivative instruments, liabilities Derivative Liability Travel credits for future travel Travel credits for future travel Travel credits for future travel Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Major Types of Debt and Equity Securities [Domain] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Cash and Cash Equivalents [Abstract] Cash Cash Money Market Funds, at Carrying Value Money Market Funds, at Carrying Value Cash equivalents Cash Equivalents, at Carrying Value Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Available-for-sale Securities, Current [Abstract] Marketable securities, Cost Basis Available-for-sale Securities, Amortized Cost Basis Marketable securities, Unrealized Gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Marketable securities, Unrealized Losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Marketable securities, Fair Value Cash and marketables securities, Cost Basis Total Cash And Marketable Securities, Amortized Cost Basis Total Cash And Marketable Securities, Amortized Cost Basis Cash and marketable securities, Unrealized Gains Cash and Available for Sale Securities Accumulated Gross Unrealized Gain Before Tax Cash and Available for Sale Securities Accumulated Gross Unrealized Gain Before Tax Cash and marketable securities, Unrealized Losses Cash and Available for Sale Securities Accumulated Gross Unrealized Loss Before Tax Cash and Available for Sale Securities Accumulated Gross Unrealized Loss Before Tax Total cash and marketable securities Cash, Cash Equivalents, and Short-term Investments Available-for-sale Securities, Activity [Abstract] Available-for-sale Securities, Activity [Abstract] Proceeds from sales and maturities Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds Gross realized gains Available-for-sale Securities, Gross Realized Gains Gross realized losses Available-for-sale Securities, Gross Realized Losses Treasury Stock, Shares Treasury Stock, Shares Statement of Cash Flows [Abstract] Statement [Table] Statement [Table] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Statement [Line Items] Statement [Line Items] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net Income Net Income (Loss) Attributable to Parent Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Stock-based compensation and other Share-based Compensation Changes in certain assets and liabilities: Increase (Decrease) in Other Operating Assets and Liabilities, Net [Abstract] Changes in deferred tax provision Increase (Decrease) in Deferred Income Taxes (Increase) decrease in accounts receivable Increase (Decrease) in Accounts Receivable Increase (decrease) in air traffic liability Increase (Decrease) in Air Traffic Liability Increase (decrease) in deferred revenue Increase (Decrease) in Deferred Revenue Changes in pension and other postretirement benefits Increase (Decrease) in Pension Plan Obligations Other—net Other Operating Activities, Cash Flow Statement Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Property and equipment additions: Payments to Acquire Productive Assets [Abstract] Aircraft and aircraft purchase deposits Payments for Flight Equipment Other flight equipment Payments to Acquire Other Productive Assets Other property and equipment Payments to Acquire Other Property, Plant, and Equipment Total property and equipment additions Acquisition of Virgin America, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Purchases of marketable securities Payments to Acquire Marketable Securities Sales and maturities of marketable securities Proceeds from Sale and Maturity of Marketable Securities Proceeds from disposition of assets and changes in restricted deposits Payments for (Proceeds from) Other Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Long-term debt payments Common stock repurchases Payments for Repurchase of Common Stock Cash dividend paid Payments of Dividends Other financing activities Proceeds from (Payments for) Other Financing Activities Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Net increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of year Cash and cash equivalents at end of year Supplemental disclosure: Supplemental Cash Flow Information [Abstract] Cash paid during the year for: Caid Paid Refunded [Abstract] Caid Paid Refunded [Abstract] Interest, net of amount capitalized Interest Paid, Net Income taxes, net of refunds received Income Taxes Paid, Net Organization and Basis of Accounting, Policy [Policy Text Block] Basis of Accounting, Policy [Policy Text Block] Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents, Policy [Policy Text Block] Marketable Securities, Available-for-sale Securities, Policy [Policy Text Block] Marketable Securities, Available-for-sale Securities, Policy [Policy Text Block] Receivables, Policy [Policy Text Block] Receivables, Policy [Policy Text Block] Inventory, Policy [Policy Text Block] Inventory, Policy [Policy Text Block] Property, Plant and Equipment, Policy [Policy Text Block] Property, Plant and Equipment, Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Intangible Assets Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block] Internal Use Software, Policy [Policy Text Block] Internal Use Software, Policy [Policy Text Block] Revenue Recognition, Deferred Revenue [Policy Text Block] Revenue Recognition, Deferred Revenue [Policy Text Block] Lease, Policy [Policy Text Block] Lease, Policy [Policy Text Block] Leased Aircraft Return Costs [Policy Text Block] Leased Aircraft Return Costs [Policy Text Block] Leased Aircraft Return Costs [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] Frequent Flier Program, Policy [Policy Text Block] Frequent Flier Program, Policy [Policy Text Block] Advertising Cost, Policy, Expensed Advertising Cost [Policy Text Block] Advertising Cost, Policy, Expensed Advertising Cost [Policy Text Block] Derivatives, Policy [Policy Text Block] Derivatives, Policy [Policy Text Block] Fair Value of Financial Instruments, Policy [Policy Text Block] Fair Value of Financial Instruments, Policy [Policy Text Block] Income Tax, Policy [Policy Text Block] Income Tax, Policy [Policy Text Block] Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Earnings Per Share, Policy [Policy Text Block] Earnings Per Share, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] Line of Credit Facility [Table] Line of Credit Facility [Table] Credit Facilities 1 and 2 [Member] Credit Facilities 1 and 2 [Member] Credit Facilities 1 and 2 [Member] Credit Facility 1 [Member] Credit Facility 1 [Member] Credit Facility 1 [Member] Credit Facility 2 [Member] Credit Facility 2 [Member] Credit Facility 2 [Member] Credit Facility 3 [Member] Credit Facility 3 [Member] Credit Facility 3 [Member] Line of Credit Facility [Axis] Lender Name [Axis] Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Secured by aircraft [Member] Secured by aircraft [Member] Secured by aircraft [Member] Secured by other [Member] Secured by other [Member] Secured by other [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Line of credit facility, borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Number of credit facilities Line of Credit Facility, Number of Credit Facilities Line of Credit Facility, Number of Credit Facilities Number of aircrafts used as collateral Long-term Debt, Number of Collateral Long-term Debt, Number of Collateral Number of credit facilities, no borrowing Line of Credit Facility, Number of Credit Facilities, No Borrowing Line of Credit Facility, Number of Credit Facilities, No Borrowing Line of credit facility, asset restrictions, unrestricted cash and marketable securities Line of Credit Facility, Asset Restrictions, Unrestricted Cash and Marketable Securities Line of Credit Facility, Asset Restrictions, Unrestricted Cash and Marketable Securities CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES - MATURITIES [Abstract] CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES - MATURITIES [Abstract] Schedule of Debt Investment Maturities [Table] Schedule of Debt Investment Maturities [Table] Schedule of Debt Investment Maturities Schedule of Debt Investment Maturities [Line Items] Schedule of Debt Investment Maturities [Line Items] [Line Items] for Schedule of Debt Investment Maturities Cost Basis [Abstract] Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Rolling Maturity [Abstract] Due in one year or less Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Amortized Cost Basis Due after one year through five years Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Amortized Cost Basis Due after five years through 10 years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Amortized Cost Basis Due after 10 years Available-for-sale Securities, Debt Maturities, Rolling after Year Ten, Amortized Cost Basis Fair Value [Abstract] Available-for-sale Securities, Debt Maturities, Fair Value, Rolling Maturity [Abstract] Due in one year or less Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Fair Value Due after one year through five years Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Fair Value Due after five years through 10 years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Fair Value Due after 10 years Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value Marketable securities, Fair Value Pension and Other Postretirement Defined Benefit Plans, Liabilities [Abstract] Accrued benefit liability-long term Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent Plan assets-long term (within Other noncurrent assets) Defined Benefit Plan, Assets for Plan Benefits, Noncurrent Total liability recognized Pension and Other Postretirement Defined Benefit Plans, Liabilities Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax [Abstract] Prior service credit Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax Net loss Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax Amount recognized in AOCL (pretax) Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax Settlement expense (special item) Number of defined benefit plans Number of Defined Benefit Plans Number of Defined Benefit Plans Number of defined contribution plans Number of Defined Contribution Plans Number of Defined Contribution Plans Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] Benefit obligations, Weighted-average discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Benefit obligations, Rate of compensation increase Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Net period benefit costs, Weighted-average discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Net period benefit costs, Weighted-average expected return on assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets Net period benefit costs, Rate of compensation increase Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Statement of Stockholders' Equity [Abstract] Common Stock Common Stock [Member] Capital in Excess of Par Value Additional Paid-in Capital [Member] Treasury Stock, at Cost Treasury Stock [Member] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Retained Earnings Retained Earnings [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Stockholders' Equity Stockholders' Equity Attributable to Parent Common Stock Outstanding Common Stock, Shares, Outstanding Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax Common stock repurchase (in shares) Common stock repurchase Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Cash dividend declared Dividends, Cash Stock issued for employee stock purchase plan (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Stock issued for employee stock purchase plan Stock Issued During Period, Value, Employee Stock Purchase Plan Stock issued under stock plans (in shares) Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Stock issued under stock plans Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Stockholders' Equity Common Stock Outstanding Advertising expense Advertising Expense Unrecorded Unconditional Purchase Obligation [Table] Unrecorded Unconditional Purchase Obligation [Table] Other Commitments [Axis] Other Commitments [Axis] Other Commitments [Domain] Other Commitments [Domain] Aircraft Maintenance Deposits [Member] Aircraft Maintenance Deposits [Member] Aircraft Maintenance Deposits [Member] Aircraft Maintenance and Parts Management [Member] Aircraft Maintenance and Parts Management [Member] Aircraft Maintenance and Parts Management [Member] Lease Arrangement, Type [Axis] Lease Arrangement, Type [Axis] Lease Arrangement, Type [Domain] Lease Arrangement, Type [Domain] Capacity Purchase Agreement with SkyWest [Member] Capacity Purchase Agreement with SkyWest [Member] Capacity Purchase Agreement with SkyWest [Member] Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] Property Subject to or Available for Operating Lease [Axis] Property Subject to or Available for Operating Lease [Axis] Property Subject to or Available for Operating Lease [Domain] Property Subject to or Available for Operating Lease [Domain] Property Subject to Operating Lease [Member] Property Subject to Operating Lease [Member] Property Available for Operating Lease [Member] Property Available for Operating Lease [Member] B-737 [Member] A-320-Neo [Member] A-320-Neo [Member] B737-900ER [Member] B737-900ER [Member] B737 MAX [Member] B-737-Max [Member] Q400 [Member] Q400 [Member] Q400 [Member] Airbus [Member] Airbus [Member] Airbus [Member] E-175 [Domain] E-175 [Domain] E-175 [Domain] E175 [Member] E175 [Member] E175 [Member] A321neo [Member] A321neo [Member] A321neo [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Aircraft Leases [Member] Aircraft [Member] Aircraft [Member] Facility Leases [Member] Building [Member] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Aircraft Commitments [Member] Capital Addition Purchase Commitments [Member] Capacity Purchase Agreements[Member] Capacity [Member] Legal Entity [Axis] Entity [Domain] Unrecorded Unconditional Purchase Obligation [Line Items] Unrecorded Unconditional Purchase Obligation [Line Items] Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 2017 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2018 Operating Leases, Future Minimum Payments, Due in Two Years 2019 Operating Leases, Future Minimum Payments, Due in Three Years 2020 Operating Leases, Future Minimum Payments, Due in Four Years 2021 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total Operating Leases, Future Minimum Payments Due Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] 2017 Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months 2018 Unrecorded Unconditional Purchase Obligation, Due within Two Years 2019 Unrecorded Unconditional Purchase Obligation, Due within Three Years 2020 Unrecorded Unconditional Purchase Obligation, Due within Four Years 2021 Unrecorded Unconditional Purchase Obligation, Due within Five Years Thereafter Unrecorded Unconditional Purchase Obligation, Due after Five Years Total Unrecorded Unconditional Purchase Obligation Other Commitment, Due after Fifth Year Other Commitment, Due after Fifth Year Other Commitment, Due in Fifth Year Other Commitment, Due in Fifth Year Other Commitment, Due in Fourth Year Other Commitment, Due in Fourth Year Other Commitment, Due in Third Year Other Commitment, Due in Third Year Other Commitment, Due in Second Year Other Commitment, Due in Second Year Other Commitment, Due in Next Twelve Months Other Commitment, Due in Next Twelve Months Operating leases, number of leased assets (in aircraft) Property Subject to or Available for Operating Lease, Number of Units Property Subject to or Available for Operating Lease, Number of Optional Additional Units Property Subject to or Available for Operating Lease, Number of Optional Additional Units Property Subject to or Available for Operating Lease, Number of Optional Additional Units Rent expense Operating Leases, Rent Expense Commited to purchase (in aircraft) Unrecorded Unconditional Purchase Obligation, Minimum Quantity Required Option to purchase additional (in aircraft) Unrecorded Unconditional Purchase Obligation, Option to Purchase Additional Unrecorded Unconditional Purchase Obligation, Option to Purchase Additional Capacity purchase arrangements, Carriers Airline, Capacity Purchase Arrangements, Carriers Airline, Capacity Purchase Arrangements, Carriers Capacity purchase arrangements, Percent Airline, Capacity Purchase Arrangements, Percent Airline, Capacity Purchase Arrangements, Percent Other Commitment Other Commitment 2017 Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months 2018 Defined Benefit Plan, Expected Future Benefit Payments, Year Two 2019 Defined Benefit Plan, Expected Future Benefit Payments, Year Three 2020 Defined Benefit Plan, Expected Future Benefit Payments, Year Four 2021 Defined Benefit Plan, Expected Future Benefit Payments, Year Five 2022– 2026 Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter INCOME TAXES Income Tax Disclosure [Text Block] Schedule of Assumptions Used [Table Text Block] Schedule of Assumptions Used [Table Text Block] Schedule of Allocation of Plan Assets [Table Text Block] Schedule of Allocation of Plan Assets [Table Text Block] Schedule of Net Funded Status [Table Text Block] Schedule of Net Funded Status [Table Text Block] Schedule of Amounts Recognized in Balance Sheet [Table Text Block] Schedule of Amounts Recognized in Balance Sheet [Table Text Block] Schedule of Net Benefit Costs [Table Text Block] Schedule of Net Benefit Costs [Table Text Block] Schedule of Expected Benefit Payments [Table Text Block] Schedule of Expected Benefit Payments [Table Text Block] Prior service credit Defined Benefit Plan, Future Amortization of Prior Service Cost (Credit) Net loss Defined Benefit Plan, Future Amortization of Gain (Loss) Variable incentive pay Other Labor-related Expenses Operational Performance Rewards Program entitles all Air Group employees to maximum quarterly payouts (in dollars per quarter) Quarterly Payout to Employee, Under Employee Incentive Plan, Maximum Quarterly Payout to Employee, Under Employee Incentive Plan, Maximum Subsequent Event [Table] Subsequent Event [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Cash dividend declared per share Common Stock, Dividends, Per Share, Declared Cash dividend paid Dividend increase Dividend Increase Dividend Increase U.S. federal tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Income before income tax Expected tax expense Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Nondeductible expenses Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount State income taxes Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount State income sourcing Effective Income Tax Rate Reconciliation, State and Local Income Sourcing, Amount Effective Income Tax Rate Reconciliation, State and Local Income Sourcing, Amount Other—net Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount Effective tax rate Effective Income Tax Rate Reconciliation, Percent Special tax expense (benefit) Special Tax Expense (Benefit) Special Tax Expense (Benefit) Additions based on tax positions and settlements related to the current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block] Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block] Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block] Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block] Total expense for the defined-contribution plans Defined Contribution Plan, Cost Recognized Statement of Financial Position [Abstract] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] ASSETS Assets [Abstract] Current Assets Assets, Current [Abstract] Cash and cash equivalents Marketable securities Marketable Securities, Current Receivables—less allowance for doubtful accounts of $1 and $1 Receivables, Net, Current Inventories and supplies—net Inventory, Net Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total Current Assets Assets, Current Property and Equipment Property, Plant and Equipment, Net [Abstract] Aircraft and other flight equipment Flight Equipment, Gross Other property and equipment Property, Plant and Equipment, Other, Gross Deposits for future flight equipment Deposits on Flight Equipment Property and Equipment Property, Plant and Equipment, Gross Less accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Total Property and Equipment—Net Property, Plant and Equipment, Net Other Assets [Abstract] Other Assets [Abstract] Goodwill Goodwill Intangible assets Intangible Assets, Net (Excluding Goodwill) Other noncurrent assets Other Assets, Noncurrent Total Other Assets Other Assets Total Assets LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Equity [Abstract] Current Liabilities Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued wages, vacation and payroll taxes Employee-related Liabilities, Current Air traffic liability Deferred Air Traffic Revenue, Current Current portion of long-term debt Debt, Current Total Current Liabilities Liabilities, Current Long-Term Debt, Net of Current Portion Other Liabilities and Credits Liabilities, Noncurrent [Abstract] Deferred income taxes Deferred Tax Liabilities, Net, Noncurrent Obligation for pension and postretirement medical benefits Other Liabilities and Credits Totals Liabilities, Other than Long-term Debt, Noncurrent Commitments and Contingencies Commitments and Contingencies Shareholders' Equity Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract] Preferred stock, $0.01 par value, Authorized: 5,000,000 shares, none issued or outstanding Preferred Stock, Value, Issued Common stock, $0.01 par value, Authorized: 200,000,000 shares, Issued: 2016 - 129,189,634 shares; 2015 - 128,442,099 shares, Outstanding: 2016 - 123,328,051 shares; 2015 - 125,175,325 shares Common Stock, Value, Issued Capital in excess of par value Additional Paid in Capital, Common Stock Treasury stock (common), at cost: 2016 - 5,861,583 shares; 2015 - 3,266,774 shares Treasury Stock, Value Accumulated other comprehensive loss Retained earnings Retained Earnings (Accumulated Deficit) Shareholders' Equity Total Total Liabilities and Shareholders' Equity Liabilities and Equity Statement of Comprehensive Income [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), Tax [Abstract] Related to marketable securities: Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax [Abstract] Unrealized holding gains (losses) arising during the period Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Reclassification of (gains) losses into Other-net nonoperating income (expense) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Income tax benefit (expense) Other Comprehensive Income (Loss), Available-for-sale Securities, Tax Marketable securities, net of tax Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Related to employee benefit plans: Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract] Actuarial gains (losses) related to pension and other postretirement benefit plans Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax Reclassification of net pension expense into Wages and benefits Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, before Tax Income tax benefit (expense) Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Tax Total Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax Related to interest rate derivative instruments: Derivative Instruments and Hedges, Assets [Abstract] Unrealized holding gains (losses) arising during the period Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax Reclassification of losses into Aircraft rent Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax Income tax benefit (expense) Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax Interest rate derivative instruments, net of tax Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Other comprehensive loss Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Table Text Block] Derivative Instruments, Gain (Loss) [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Summary of Income Tax Contingencies [Table Text Block] Summary of Income Tax Contingencies [Table Text Block] Negative cash balance Bank Overdrafts Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Change in Accounting Estimate by Type [Axis] Change in Accounting Estimate by Type [Axis] Change in Accounting Estimate, Type [Domain] Change in Accounting Estimate, Type [Domain] Service Life [Member] Service Life [Member] B737 Property, Plant and Equipment by Type [Axis] Property, Plant and Equipment, Type [Domain] Aircraft [Member] Buildings [Member] Minor building and land improvements [Member] Minor Building and Land Improvements [Member] Minor Building and Land Improvements [Member] Computer hardware and software [Member] Technology Equipment [Member] Other furniture and equipment [Member] Office Equipment [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Estimated useful life Property, Plant and Equipment, Useful Life Depreciation, decrease Depreciation New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Special Charges [Member] Pension Plan [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Special Item, net of tax Special Item, net of tax Special Item, net of tax Gain related to litigation settlement Gain (Loss) Related to Litigation Settlement Document and Entity Information [Abstract] Document and Entity Information [Abstract] Document Information [Table] Document Information [Table] Legal Entity [Axis] Entity [Domain] Entity Information [Line Items] Entity Information [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Public Float Entity Public Float Document Period End Date Document Period End Date Schedule of Long-term Debt Instruments [Table Text Block] Schedule of Long-term Debt Instruments [Table Text Block] Schedule of Maturities of Long-term Debt [Table Text Block] Schedule of Maturities of Long-term Debt [Table Text Block] Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current Stockholders' Equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred Stock, par value Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Preferred stock, shares outstanding Preferred Stock, Shares Outstanding Common stock, shares issued Common Stock, Shares, Issued Common Stock, Shares, Outstanding Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Airport Slots [Member] Airport Slots [Member] Airport Slots [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Airport Gates [Member] Airport Gates [Member] Airport Gates [Member] Customer Relationships [Member] Customer Relationships [Member] Percentage of interests acquired Business Acquisition, Percentage of Voting Interests Acquired Number of Daily Departures Number of Daily Departures Number of Daily Departures Revenue Repayments of related party debt Repayments of Related Party Debt Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Indefinite-lived intangible assets acquired Indefinite-lived Intangible Assets Acquired Finite-lived intangible assets acquired Finite-lived Intangible Assets Acquired Finite-Lived intangible asset, useful Life Finite-Lived Intangible Asset, Useful Life Beginning balance Unrecognized Tax Benefits Additions from acquisitions Unrecognized Tax Benefits, Increase Resulting from Acquisition Ending balance Stock options [Member] Employee Stock Option [Member] Stock awards [Member] Restricted Stock [Member] Deferred stock awards [Member] Deferred Stock Awards [Member] Deferred Stock Awards [Member] Stock-based compensation Allocated Share-based Compensation Expense Tax benefit related to stock-based compensation Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Unrecognized stock-based compensation for non-vested options and awards Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized stock-based compensation awards weighted-average period Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Shares authorized under stock-based compensation plans (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Shares remaining available for future grants (shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected term Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Weighted-average grant date fair value per share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Estimated fair value of options granted (millions) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Estimated Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Estimated Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (in Shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Canceled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Canceled Share-based Compensation Arrangement by Share-based Payment Award, Options, Canceled Forfeited or expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Outstanding, ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Outstanding, beginning balance, Weighted-Average Exercise Price Per Share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted, Weighted-Average Exercise Price Per Share (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised, Weighted-Average Exercise Price Per Share (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Canceled, Weighted-Average Exercise Price Per Share (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Canceled in Period, Weighted Average Exercise Price Share-based Compensation Arrangements by Share-based Payment Award, Options, Canceled in Period, Weighted Average Exercise Price Fofeited or expired, Weighted-Average Exercise Price Per Share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Outstanding, ending balance, Weighted-Average Exercise Price Per Share (in dollars per share) Outstanding, Weighted-Average Contractual Life Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Outstanding, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Exercisable, Outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Exercisable, Weighted-Average Exercise Price Per Share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Exercisable, Weighted-Average Contractual Life Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Exercisable, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract] Vested or expected to vest, Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Vested or expected to vest, Weighted-Average Exercise Price Per Share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Vested or expected to vest, Weighted-Average Contractual Life Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Vested or expected to vest, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Intrinsic value of option exercises Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Cash received from stock option exercises Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options Tax benefit related to stock option exercises Deferred Tax Expense from Stock Options Exercised Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Non-vested, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Non-vested, ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Non-vested, beginning balance, Weighted-Average Grant Date Fair Value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted, Weighted-Average Grant Date Fair Value (in dollars 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 Vested, Weighted-Average Grant Date Fair Value (in dollars 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 Forfeited, Weighted-Average Grant Date Fair Value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Non-vested, ending balance, Weighted-Average Price Per Share (in dollars per share) Non-vested, Weighted-Average Contractual Life Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Non-vested, Total Instrinsic Value (in dollars) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Total Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Total Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract] Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract] Cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Receivables Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Prepaid expenses and other current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Property and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Total assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Acquired Including Goodwill Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Acquired Including Goodwill Accounts payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Accrued wages, vacation and payroll taxes Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Accrued Wages, Vacation and Payroll Taxes Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Accrued Wages, Vacation and Payroll Taxes Air traffic liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Air Traffic Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Air Traffic Liabilities Other accrued liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Current portion of long-term debt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt Long-term debt, net of current portion Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt Deferred income taxes Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Deferred revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Deferred Revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Deferred Revenue Other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other Total liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Total purchase price Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Income Statement [Abstract] Operating Revenues Passenger, Mainline Passenger, Regional Total passenger revenue Other—net Operating Expenses Wages and benefits Labor and Related Expense Aircraft fuel, including hedging gains and losses Aircraft maintenance Aircraft Maintenance, Materials, and Repairs Aircraft rent Aircraft Rental Landing fees and other rentals Landing Fees and Other Rentals Contracted services Professional and Contract Services Expense Selling expenses Selling Expense Food and beverage service Food and Beverage, Cost of Sales Third-party regional carrier expense Regional Carrier Expense Regional Carrier Expense Third-party regional carrier expense Other Cost and Expense, Operating Operating Income Operating Income (Loss) Interest capitalized Interest Costs Capitalized Adjustment Other—net Other Nonoperating Income (Expense) Income tax expense Net Income Basic Earnings Per Share: Earnings Per Share, Basic Diluted Earnings Per Share: Earnings Per Share, Diluted Shares used for computation: Earnings Per Share [Abstract] Basic Weighted Average Number of Shares Outstanding, Basic Diluted Weighted Average Number of Shares Outstanding, Diluted Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Carrying Amount [Member] Reported Value Measurement [Member] Fair Value [Member] Estimate of Fair Value Measurement [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Long-term debt Notes Payable, Fair Value Disclosure