Document and Entity Information [Abstract] Document and Entity Information [Abstract] Document Information [Table] Document Information [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Entity Information [Line Items] Entity Information [Line Items] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Entity Filer Category Entity Filer Category Document Fiscal Period Focus Document Fiscal Period Focus Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Fair Value Disclosures [Abstract] Fair Value, Measurement Inputs, Disclosure [Table Text Block] Fair Value, Measurement Inputs, Disclosure [Text Block] Fair Value, by Balance Sheet Grouping [Table Text Block] Fair Value, by Balance Sheet Grouping [Table Text Block] Equity [Abstract] Common Stock Changes [Table] Stock Split [Table] Stock Split [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] pre-change [Domain] prestocksplit [Domain] pre-stock split [Domain] Common Stock Changes [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 Common stock, shares outstanding Common Stock, Shares, Outstanding Derivative Instruments and Hedging Activities Disclosure [Abstract] 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] Cash, Cash Equivalents, and Short-term Investments [Abstract] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] U.S. government and agency securities [Member] US Treasury and Government [Member] Foreign government bonds [Member] Foreign Government Debt Securities [Member] Asset-backed securities [Member] Asset-backed Securities, Securitized Loans and Receivables [Member] Mortgage-backed securities [Member] Collateralized Mortgage Backed Securities [Member] Corporate notes and bonds [Member] Corporate Debt Securities [Member] Municipal securities [Member] US States and Political Subdivisions Debt Securities [Member] 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 and other securities Money Market Funds, 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, Gross Unrealized Gain Marketable securities, Unrealized Losses Available-for-sale Securities, Gross Unrealized Loss Marketable securities, Fair Value Available-for-sale Securities, Current Cash and marketables securities, Cost Basis Total Cash And Marketable Securities, Amortized Cost Basis Total Cash And Marketable Securities, Amortized Cost Basis 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 OPERATING SEGMENT INFORMATION [Abstract] OPERATING SEGMENT INFORMATION [Abstract] Statement [Table] Statement [Table] Statement, Business Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Alaska Airlines [Member] Alaska Airlines [Member] Alaska Airlines [Member] Horizon [Member] Horizon [Member] Horizon Segment [Member] Parent [Member] Segment Reconciling Items [Member] Intersegment Elimination [Member] Intersegment Eliminations [Member] Statement [Line Items] Statement [Line Items] Total assets Assets 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] Statement of Financial Position [Abstract] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] 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 Treasury Stock, Shares Treasury Stock, Shares DERIVATIVE INSTRUMENTS Derivative Instruments and Hedging Activities Disclosure [Text Block] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] U.S. government and agency securities [Member] Derivative Instrument [Axis] Derivative Contract [Domain] Fuel hedge contracts [Member] Commodity Contract [Member] Interest rate swaps agreements [Member] Interest Rate Swap [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Level 2 [Member] Fair Value, Inputs, Level 2 [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] Marketable securities Available-for-sale Securities Derivative instruments, assets Derivative Asset Derivative instruments, liabilities Derivative Liability Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Air Group Adjusted [Member] Air Group Adjusted [Member] Air Group Adjusted [Member] Alaska Mainline [Member] Alaska Mainline [Member] Alaska Mainline [Member] Alaska Regional [Member] Alaska Regional [Member] Alaska Regional [Member] Special Revenue and Charges [Member] Special Revenue and Charges [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Airline, Capacity Purchase Arrangements, Percent Airline, Capacity Purchase Arrangements, Percent Airline, Capacity Purchase Arrangements, Percent Operating revenues Revenues [Abstract] Passenger, Mainline Passenger Revenue, Mainline Passenger, Regional Passenger Revenue, Regional Total passenger revenue Passenger Revenue Segment Reporting Information, Intersegment Revenue Revenues Freight and mail Cargo and Freight Revenue Other - net 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 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, Extraordinary Items, Noncontrolling Interest 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] Line of Credit Facility [Table] Line of Credit Facility [Table] 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, Number of Credit Facilities Line of Credit Facility, Number of Credit Facilities Line of Credit Facility, Number of Credit Facilities Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Expiration Date Line of Credit Facility, Expiration Date Line of Credit Facility, Asset Restrictions Line of Credit Facility, Asset Restrictions, Unrestricted Cash and Marketable Securities Line of Credit Facility, Asset Restrictions, Unrestricted Cash and Marketable Securities Income Statement [Abstract] Statement, Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Operating Revenues Passenger, Mainline Passenger, Regional Other - net Other Revenue, Net Special Revenue Special Revenue Special Revenue Operating Expenses Wages and benefits Labor and Related Expense Variable incentive pay Other Labor-related Expenses 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 Depreciation and amortization Depreciation, Depletion and Amortization Food and beverage service Food and Beverage, Cost of Sales Other Other Cost and Expense, Operating Operating Income Operating Income (Loss) Interest expense Interest Costs Capitalized Adjustment Interest Costs Capitalized Adjustment Other - net Other Nonoperating Income (Expense) Income before income tax Income tax expense Income Tax Expense (Benefit) Net Income Net Income (Loss) Attributable to Parent 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 shares Weighted Average Number of Shares Outstanding, Basic Diluted shares Weighted Average Number of Shares Outstanding, Diluted Common Stock, Dividends, Per Share, Declared Common Stock, Dividends, Per Share, Declared Accounting Policies [Abstract] Basis of Accounting, Policy [Policy Text Block] Basis of Accounting, Policy [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] SHAREHOLDERS' EQUITY Stockholders' Equity Note Disclosure [Text Block] GENERAL AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Significant Accounting Policies [Text Block] Compensation and Retirement Disclosure [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Domain] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Qualified Defined Benefit [Member] Pension Plan, Defined Benefit [Member] Nonqualified Defined Benefit [Member] Other Pension Plan, Defined Benefit [Member] Postretirement Medical Benefits [Member] Other Postretirement Benefit Plan, Defined Benefit [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 (gain) Defined Benefit Plan, Amortization of Gains (Losses) Net pension expense Defined Benefit Plan, Net Periodic Benefit Cost 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] September 2012 Stock Repurchase Program [Member] $250 million Repurchase Program [Member] $250 million Repurchase Program February 2012 Stock Repurchase Program [Member] February 2012 Stock Repurchase Program [Member] February 2012 Stock Repurchase Program [Member] June 2011 Stock Repurchase Program [Member] June 2011 Stock Repurchase Program [Member] June 2011 Stock Repurchase Program [Member] May 2014 Stock Repurchase Program [Member] [Domain] $650 million Repurchase Program [Member] [Domain] $650 million Repurchase Program [Member] [Domain] Class of Stock [Line Items] Class of Stock [Line Items] Stock Repurchase Program, Authorized Amount Stock Repurchase Program, Authorized Amount Stock Repurchased During Period, Shares Stock Repurchased During Period, Shares Stock Repurchased During Period, Value Stock Repurchased During Period, Value CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES Cash, Cash Equivalents, and Marketable Securities [Text Block] MILEAGE PLAN [Abstract] MILEAGE PLAN [Abstract] Schedule Of Mileage Plan [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] Liabilities From Mileage Plan [Member] Liabilities From Mileage Plan [Member] Liabilities From Mileage Plan [Member] Revenue From Mileage Plan [Member] Revenue From Mileage Plan [Member] Revenue From Mileage Plan [Member] Mileage Plan [Line Items] Mileage Plan [Line Items] Mileage Plan [Line Items] Other accrued liabilities Accrued Liabilities, Current Deferred revenue Deferred Revenue Other liabilities Other Liabilities, Noncurrent Liabilities Liabilities Total passenger revenue Other - net Total Mileage Plan Revenues Mileage Plan Revenue Mileage Plan Revenue 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] Scheduled Debt Payments [Member] Scheduled Debt Payments [Member] Scheduled Debt Payments [Member] Fixed-rate notes payable due through 2024 Fixed rate notes payable due through 2024 [Member] Fixed rate notes payable due through 2024 Variable-rate notes payable due through 2025 Variable rate notes payable due through 2023 [Member] Variable rate notes payable due through 2023 [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Long-term Debt Long-term Debt 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 Debt payments Debt Instrument, Periodic Payment Long-term Debt, Fiscal Year Maturity [Abstract] Remainder of 2014 Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year 2015 Long-term Debt, Maturities, Repayments of Principal in Year Two 2016 Long-term Debt, Maturities, Repayments of Principal in Year Three 2017 Long-term Debt, Maturities, Repayments of Principal in Year Four 2018 Long-term Debt, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Proceeds from issuance of debt Proceeds from Issuance of Secured Debt Statement of Comprehensive Income [Abstract] Net Income 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 effect 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] Reclassification of net pension expense into Wages and benefits Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax Income tax effect Other Comprehensive Income (Loss), Tax Employee benefit plans, net of tax 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), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax Reclassification of (gains) losses into Aircraft rent Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax Income tax effect 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 income Other Comprehensive Income (Loss), Net of Tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Payments of Dividends Payments of Dividends 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] ASSETS Assets [Abstract] Current Assets Assets, Current [Abstract] Cash and cash equivalents Marketable securities Marketable Securities, Current Receivables - net Receivables, Net, Current Inventories and supplies - net Inventory, Net Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Current 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 Total 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 Other Assets, Noncurrent 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 Other accrued liabilities 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 Deferred revenue Obligation for pension and postretirement medical benefits Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent Other liabilities Other Liabilities and Credits Totals Liabilities, Noncurrent Commitments and Contingencies Commitments and Contingencies Shareholders' Equity Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract] Preferred stock, $1 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: 2014 - 136,845,596 shares; 2013 - 137,533,382 shares, Outstanding: 2014 - 136,738,034; 2013 - 137,491,906 Common Stock, Value, Issued Capital in excess of par value Additional Paid in Capital, Common Stock Treasury stock (common), at cost: 2014 - 107,562 shares; 2013 - 41,476 shares Treasury Stock, Value Accumulated other comprehensive (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Retained earnings Retained Earnings (Accumulated Deficit) Total Shareholders' Equity Stockholders' Equity Attributable to Parent Total Liabilities and Shareholders' Equity Liabilities and Equity Operating Segment Information Segment Reporting Disclosure [Text Block] Derivative [Table] Derivative [Table] Hedging Designation [Axis] Hedging Designation [Domain] Not Designated as Hedging Instrument [Member] Not Designated as Hedging Instrument [Member] Derivative Instruments Designated as Hedges [Member] Designated as Hedging Instrument [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] Fuel hedge contracts outstanding (in barrels) Derivative, Nonmonetary Notional Amount Operating Leases, Number of Units (in Aircraft) Operating Leases, Number of Units Operating Leases, Number of Units Net cash received (paid) to for new positions and settlements Payments for (Proceeds from) Hedge, Investing Activities Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Segment Reporting Information, by Segment [Table Text Block] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [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 Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Derivative Instrument Risk [Axis] Derivative Contract Type [Domain] Hedging Designation [Axis] Hedging Designation [Domain] Derivative Instruments Not Designated as Hedges [Member] Derivatives, Fair Value, by Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Fuel hedge contracts [Member] Fuel Hedge Contracts, Current [Member] Fuel Hedge Contracts, Current [Member] Fuel hedge contracts, noncurrent assets [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] Gains (losses) in AOCL [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) Derivative Gain (Loss) in Accumulated Other Comprehensive Loss To Be Reclassified Within Next Twelve Months Price Risk Cash Flow Hedge Unrealized Gain (Loss) to be Reclassified During Next 12 Months Posted collateral Derivative, Collateral, Right to Reclaim Cash 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] EMPLOYEE BENEFIT PLANS Pension and Other Postretirement Benefits Disclosure [Text Block] Prospective Adoption of New Accounting Pronouncements [Abstract] New Accounting Pronouncements and Changes in Accounting Principles [Text Block] New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Unrecorded Unconditional Purchase Obligation [Table] Unrecorded Unconditional Purchase Obligation [Table] 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] Assets Leased to Others [Member] Assets Leased to Others [Member] Non Operating Aircraft [Member] Non Operating Aircraft [Member] Non Operating Aircraft [Member] B737 [Member] B737 [Member] B737-900ER [Member] B737-900ER [Member] B737 MAX [Member] B737 MAX [Member] B737 MAX [Member] Q400 [Member] Q400 [Member] Q400 [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] Engine Maintenance [Member] Engine Maintenance [Member] Unrecorded Unconditional Purchase Obligation [Line Items] Unrecorded Unconditional Purchase Obligation [Line Items] Operating Leases, Number of Units Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Remainder of 2014 Operating Leases, Future Minimum Payments, Remainder of Fiscal Year 2015 Operating Leases, Future Minimum Payments, Due in Two Years 2016 Operating Leases, Future Minimum Payments, Due in Three Years 2017 Operating Leases, Future Minimum Payments, Due in Four Years 2018 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] Remainder of 2014 Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year 2015 Unrecorded Unconditional Purchase Obligation, Due within Two Years 2016 Unrecorded Unconditional Purchase Obligation, Due within Three Years 2017 Unrecorded Unconditional Purchase Obligation, Due within Four Years 2018 Unrecorded Unconditional Purchase Obligation, Due within Five Years Thereafter Unrecorded Unconditional Purchase Obligation, Due after Five Years Total Unrecorded Unconditional Purchase Obligation Rent Expense Operating Leases, Rent Expense Committed to Purchase (in Aircraft) Unrecorded Unconditional Purchase Obligation, Minimum Quantity Required Options to Purchase Additional (in Aircraft) Unrecorded Unconditional Purchase Obligation, Option to Purchase Additional Unrecorded Unconditional Purchase Obligation, Option to Purchase Additional Airline, Capacity Purchase Arrangements, Carriers Airline, Capacity Purchase Arrangements, Carriers Airline, Capacity Purchase Arrangements, Carriers COMMITMENTS Commitments Disclosure [Text Block] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2009-13 [Member] Accounting Standards Update 2009-13 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Special Revenue Item, Per Basic Share Special Revenue Item, Per Basic Share Special Revenue Item, Per Basic Share Special Revenue Item, Per Diluted Share Special Revenue Item, Per Diluted Share Special Revenue Item, Per Diluted Share Schedule of Change in Accounting Estimate [Table] Schedule of Change in Accounting Estimate [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Special Revenue [Member] Special Mileage Plan Revenue [Member] Special Revenue [Member] 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] Original Estimate [Member] Original Estimate [Member] Original Estimate [Member] Revised Estimate [Member] Revised Estimate [Member] Revised Estimate [Member] Change in Accounting Estimate [Line Items] Change in Accounting Estimate [Line Items] Percent of Mileage Breakage Percent of Mileage Breakage Percent of Mileage Breakage Change in Accounting Estimate, Financial Effect Change in Accounting Estimate, Financial Effect Schedule of Prospective Adoption of New Accounting Pronouncements [Table Text Block] Schedule of Prospective Adoption of New Accounting Pronouncements [Table Text Block] Scenario [Axis] Marketable securities Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Employee benefit plans Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax 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) Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] 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] 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 income taxes Increase (Decrease) in Deferred Income Taxes Increase in air traffic liability Increase (Decrease) in Air Traffic Liability Increase (decrease) in deferred revenue Increase (Decrease) in Deferred Revenue 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 Payments to Acquire Property, Plant, and Equipment 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 Repayments of Long-term Debt Common stock repurchases Payments for Repurchase of Common Stock Payments of Dividends Other financing activities Proceeds from (Payments for) Other Financing Activities Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Net 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 the period Supplemental disclosure: Supplemental Cash Flow Information [Abstract] Cash paid during the period for: Caid Paid Refunded [Abstract] Caid Paid Refunded [Abstract] Interest (net of amount capitalized) Interest Paid, Net Income taxes Income Taxes Paid, Net Non-cash transactions: Nonmonetary Transactions [Abstract] LONG-TERM DEBT Long-term Debt [Text Block] Frequent Flyer Plan Disclosure [Text Block] Mileage Plan Disclosure [Text Block] Mileage Plan Disclosure [Text Block] 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 Marketable securities, 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 Marketable securities, Fair Value 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] 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] Gain (losses) recognized in income Derivative, Gain (Loss) on Derivative, Net Gains (losses) recognized in other comprehensive income (OCI) Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Mileage Plan Liabilities [Table Text Block] Mileage Plan Liabilities [Table Text Block] Mileage Plan Liabilities Mileage Plan Revenue [Table Text Block] Mileage Plan Revenue [Table Text Block] Mileage Plan Revenue [Table Text Block] Schedule of Net Benefit Costs [Table Text Block] Schedule of Net Benefit Costs [Table Text Block]