$LUV
SOUTHWEST AIRLINES CO Stock $luv

$luv Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000009238021000033 Filed on February 08, 2021

Income Statement

Concept	2020 Q4	2020 Q3	2020 Q2
Revenue	$2.013B	$1.793B	$1.008B
YoY Change	-64.86%	-68.2%	-82.94%
Cost Of Revenue	$660.0M	$687.0M	$532.0M
YoY Change	-53.91%	-52.13%	-64.37%
Gross Profit	$1.353B	$1.106B	$476.0M
YoY Change	-68.52%	-73.69%	-89.22%
Gross Profit Margin	67.21%	61.68%	47.22%
Selling, General & Admin	$1.719B	$1.863B	$1.854B
YoY Change	-34.01%	-21.06%	-23.48%
% of Gross Profit	127.05%	168.44%	389.5%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$315.0M	$316.0M	$313.0M
YoY Change	0.64%	2.6%	3.99%
% of Gross Profit	23.28%	28.57%	65.76%
Operating Expenses	$2.555B	$2.666B	$2.609B
YoY Change	-29.67%	-44.69%	-47.2%
Operating Profit	-$1.169B	-$1.411B	-$1.127B
YoY Change	-275.79%	-272.28%	-216.43%
Interest Expense	-$100.0M	-$96.00M	-$80.00M
YoY Change	-10100.0%	-420.0%	-358.06%
% of Operating Profit
Other Income/Expense, Net	-$63.00M	-$131.0M	-$112.0M
YoY Change
Pretax Income	-$1.331B	-$1.542B	-$1.239B
YoY Change	-299.85%	-288.28%	-228.0%
Income Tax	-$423.0M	-$385.0M	-$324.0M
% Of Pretax Income
Net Earnings	-$908.0M	-$1.157B	-$915.0M
YoY Change	-276.65%	-275.57%	-223.48%
Net Earnings / Revenue	-45.11%	-64.53%	-90.77%
Basic Earnings Per Share	-$1.54	-$1.96	-$1.63
Diluted Earnings Per Share	-$1.54	-$1.96	-$1.63
COMMON SHARES
Basic Shares Outstanding	590.3M shares	590.0M shares	563.0M shares
Diluted Shares Outstanding		590.0M shares	563.0M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2020 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$13.33B	$14.56B	$14.46B
YoY Change	227.46%	262.6%	262.69%
Cash & Equivalents	$11.06B	$12.11B	$12.35B
Short-Term Investments	$2.271B	$2.453B	$2.106B
Other Short-Term Assets	$295.0M	$248.0M	$223.0M
YoY Change	2.79%	3.77%	-20.64%
Inventory	$414.0M	$426.0M	$422.0M
Prepaid Expenses
Receivables	$46.00M	$514.0M	$480.0M
Other Receivables	$35.00M	$12.00M	$21.00M
Total Short-Term Assets	$15.17B	$16.13B	$15.87B
YoY Change	153.98%	185.54%	185.78%
LONG-TERM ASSETS
Property, Plant & Equipment	$15.83B	$16.06B	$16.25B
YoY Change	-7.01%	-10.01%	-8.38%
Goodwill	$970.0M	$970.0M	$970.0M
YoY Change	0.0%	0.0%	0.0%
Intangibles	$295.0M	$295.0M	$295.0M
YoY Change	-0.34%	-5.14%	-5.45%
Long-Term Investments
YoY Change
Other Assets	$722.0M	$679.0M	$662.0M
YoY Change	25.13%	3.98%	-4.47%
Total Long-Term Assets	$19.42B	$19.47B	$19.72B
YoY Change	-2.54%	-6.46%	-5.26%
TOTAL ASSETS
Total Short-Term Assets	$15.17B	$16.13B	$15.87B
Total Long-Term Assets	$19.42B	$19.47B	$19.72B
Total Assets	$34.59B	$35.61B	$35.60B
YoY Change	33.57%	34.53%	34.97%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$931.0M	$980.0M	$970.0M
YoY Change	-40.85%	-23.08%	-27.07%
Accrued Expenses	$2.259B	$1.836B	$2.372B
YoY Change	29.16%	26.1%	80.38%
Deferred Revenue	$3.790B	$3.952B	$4.988B
YoY Change	-14.97%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$220.0M	$720.0M	$695.0M
YoY Change	-73.14%	13.03%	6.27%
Total Short-Term Liabilities	$7.506B	$7.804B	$9.361B
YoY Change	-16.15%	-9.56%	8.71%
LONG-TERM LIABILITIES
Long-Term Debt	$10.11B	$10.14B	$8.905B
YoY Change	447.72%	322.64%	263.62%
Other Long-Term Liabilities	$1.247B	$1.233B	$722.0M
YoY Change	76.63%	91.46%	12.99%
Total Long-Term Liabilities	$1.247B	$1.233B	$722.0M
YoY Change	76.63%	91.46%	12.99%
TOTAL LIABILITIES
Total Short-Term Liabilities	$7.506B	$7.804B	$9.361B
Total Long-Term Liabilities	$1.247B	$1.233B	$722.0M
Total Liabilities	$8.753B	$9.037B	$10.08B
YoY Change	-9.37%	-2.55%	9.01%
SHAREHOLDERS EQUITY
Retained Earnings	$14.78B	$15.69B	$16.84B
YoY Change	-17.65%	-10.5%	-0.71%
Common Stock	$5.079B	$5.063B	$5.047B
YoY Change	112.6%	114.35%	115.5%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$10.88B	$10.88B	$10.88B
YoY Change	4.16%	9.95%	15.83%
Treasury Stock Shares	297.6M shares
Shareholders Equity	$8.876B	$9.769B	$10.88B
YoY Change
Total Liabilities & Shareholders Equity	$34.59B	$35.61B	$35.60B
YoY Change	33.57%	34.53%	34.97%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2020 Q2
OPERATING ACTIVITIES
Net Income	-$908.0M	-$1.157B	-$915.0M
YoY Change	-276.65%	-275.57%	-223.48%
Depreciation, Depletion And Amortization	$315.0M	$316.0M	$313.0M
YoY Change	0.64%	2.6%	3.99%
Cash From Operating Activities	-$596.0M	-$1.050B	$897.0M
YoY Change	-172.33%	-196.24%	-7.14%
INVESTING ACTIVITIES
Capital Expenditures	-$90.00M	-$89.00M	-$112.0M
YoY Change	-65.52%	-76.33%	-51.3%
Acquisitions
YoY Change
Other Investing Activities	$181.0M	-$345.0M	$444.0M
YoY Change	-55.31%		-2214.29%
Cash From Investing Activities	$91.00M	-$434.0M	$332.0M
YoY Change	-36.81%	20.89%	-231.75%
FINANCING ACTIVITIES
Cash Dividend Paid		$0.00	$0.00
YoY Change		-100.0%	-100.0%
Common Stock Issuance & Retirement, Net		$0.00	-$2.294B
YoY Change		-100.0%	-609.78%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-541.0M	$1.242B	$7.182B
YoY Change	-40.42%	-280.0%	-1273.53%
NET CHANGE
Cash From Operating Activities	-596.0M	-$1.050B	$897.0M
Cash From Investing Activities	91.00M	-$434.0M	$332.0M
Cash From Financing Activities	-541.0M	$1.242B	$7.182B
Net Change In Cash	-1.046B	-$242.0M	$8.411B
YoY Change	-1843.33%	-676.19%	8146.08%
FREE CASH FLOW
Cash From Operating Activities	-$596.0M	-$1.050B	$897.0M
Capital Expenditures	-$90.00M	-$89.00M	-$112.0M
Free Cash Flow	-$506.0M	-$961.0M	$1.009B
YoY Change	-146.64%	-165.51%	-15.64%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000092380
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	590677474	shares
CY2020Q2	dei	Entity Public Float EntityPublicFloat	20094518012	USD
CY2020	us-gaap	Impairment Of Intangible Assets Indefinitelived Excluding Goodwill ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	0	USD
CY2020Q2	luv	Proceeds From Payroll Support Program Grant Received In June2020 ProceedsFromPayrollSupportProgramGrantReceivedInJune2020	652000000	USD
CY2020	us-gaap	Impairment Of Intangible Assets Indefinitelived Excluding Goodwill ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	0	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	78000000	USD
CY2020	dei	Document Type DocumentType	10-K
CY2019	us-gaap	Sublease Income SubleaseIncome	97000000	USD
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	1-7259
CY2020	dei	Entity Registrant Name EntityRegistrantName	SOUTHWEST AIRLINES CO.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	TX
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	74-1563240
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	P.O. Box 36611
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Dallas,
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	TX
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	75235-1611
CY2020	dei	City Area Code CityAreaCode	214
CY2020	dei	Local Phone Number LocalPhoneNumber	792-4000
CY2020	dei	Security12g Title Security12gTitle	None
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	20094518012	USD
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CY2019Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	1086000000	USD
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CY2019Q4	us-gaap	Airline Related Inventory AirlineRelatedInventory	529000000	USD
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CY2019Q4	us-gaap	Assets Current AssetsCurrent	5974000000	USD
CY2020Q4	us-gaap	Flight Equipment Gross FlightEquipmentGross	20877000000	USD
CY2019Q4	us-gaap	Flight Equipment Gross FlightEquipmentGross	21629000000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	6083000000	USD
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CY2019Q4	us-gaap	Deposits On Flight Equipment DepositsOnFlightEquipment	248000000	USD
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CY2020Q4	luv	Construction Obligation Noncurrent ConstructionObligationNoncurrent	309000000	USD
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CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-105000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-61000000	USD
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CY2020	us-gaap	Aircraft Maintenance Materials And Repairs AircraftMaintenanceMaterialsAndRepairs	750000000	USD
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CY2020	us-gaap	Investment Income Interest InvestmentIncomeInterest	32000000	USD
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CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-5.44
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CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.29
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-3074000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	2300000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	2465000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	15000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	9000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-15000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	48000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	29000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-52000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	7000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	8000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-2000000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	25000000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	26000000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-6000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-44000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-81000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	26000000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-3118000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	2219000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	2491000000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	9641000000	USD
CY2017Q4	luv	Net Accounting Pronouncement Or Change In Accounting Principle Cumulative Effect Of Change On Equity Or Net Assets NetAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets	0	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	2000000000	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	23000000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	46000000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.605
CY2018	us-gaap	Dividends Cash DividendsCash	348000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	2491000000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	9853000000	USD
CY2018Q4	luv	Net Accounting Pronouncement Or Change In Accounting Principle Cumulative Effect Of Change On Equity Or Net Assets NetAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets	55000000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	2000000000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	27000000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	55000000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.700
CY2019	us-gaap	Dividends Cash DividendsCash	377000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	2219000000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	9832000000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	451000000	USD
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	2224000000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	34000000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	17000000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.180
CY2020	us-gaap	Dividends Cash DividendsCash	94000000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Warrant Issued AdjustmentsToAdditionalPaidInCapitalWarrantIssued	40000000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Equity Component Of Convertible Debt AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt	392000000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-3118000000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	8876000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-3074000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	2300000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	2465000000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1255000000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1219000000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1201000000	USD
CY2020	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	-32000000	USD
CY2019	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	0	USD
CY2018	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	0	USD
CY2020	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-15000000	USD
CY2019	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	0	USD
CY2018	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	14000000	USD
CY2020	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	716000000	USD
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	55000000	USD
CY2018	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-301000000	USD
CY2020	us-gaap	Sale And Leaseback Transaction Gain Loss Net SaleAndLeasebackTransactionGainLossNet	-222000000	USD
CY2019	us-gaap	Sale And Leaseback Transaction Gain Loss Net SaleAndLeasebackTransactionGainLossNet	0	USD
CY2018	us-gaap	Sale And Leaseback Transaction Gain Loss Net SaleAndLeasebackTransactionGainLossNet	0	USD
CY2020	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	294000000	USD
CY2019	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	94000000	USD
CY2018	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-117000000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-415000000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-239000000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	227000000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	231000000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	298000000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	545000000	USD
CY2020	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	1623000000	USD
CY2019	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	440000000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	506000000	USD
CY2020	us-gaap	Capitalized Computer Software Impairments1 CapitalizedComputerSoftwareImpairments1	0	USD
CY2018	us-gaap	Proceeds From Convertible Debt ProceedsFromConvertibleDebt	0	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-306000000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-277000000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	0	USD
CY2020	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	9000000	USD
CY2019	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	25000000	USD
CY2018	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	-15000000	USD
CY2020	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-95000000	USD
CY2019	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-108000000	USD
CY2018	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	14000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-1127000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3987000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	4893000000	USD
CY2020	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	515000000	USD
CY2019	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	1027000000	USD
CY2018	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	1922000000	USD
CY2020	luv	Supplier Proceeds SupplierProceeds	428000000	USD
CY2019	luv	Supplier Proceeds SupplierProceeds	400000000	USD
CY2018	luv	Supplier Proceeds SupplierProceeds	0	USD
CY2020	luv	Sale Leaseback Cash Proceeds Investing SaleLeasebackCashProceedsInvesting	815000000	USD
CY2019	luv	Sale Leaseback Cash Proceeds Investing SaleLeasebackCashProceedsInvesting	0	USD
CY2018	luv	Sale Leaseback Cash Proceeds Investing SaleLeasebackCashProceedsInvesting	0	USD
CY2020	us-gaap	Payments For Construction In Process PaymentsForConstructionInProcess	0	USD
CY2019	us-gaap	Payments For Construction In Process PaymentsForConstructionInProcess	0	USD
CY2018	us-gaap	Payments For Construction In Process PaymentsForConstructionInProcess	54000000	USD
CY2020	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	5080000000	USD
CY2019	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	2122000000	USD
CY2018	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	2409000000	USD
CY2020	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	4336000000	USD
CY2019	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	2446000000	USD
CY2018	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	2342000000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
CY2020Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	697000000	USD
CY2019Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	630000000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-5000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-16000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-303000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2038000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	2294000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	5622000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	0	USD
CY2020	us-gaap	Proceeds From Notes Payable ProceedsFromNotesPayable	3683000000	USD
CY2019	us-gaap	Proceeds From Notes Payable ProceedsFromNotesPayable	0	USD
CY2018	us-gaap	Proceeds From Notes Payable ProceedsFromNotesPayable	0	USD
CY2020	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	1000000000	USD
CY2019	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
CY2018	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
CY2020	us-gaap	Proceeds From Convertible Debt ProceedsFromConvertibleDebt	2300000000	USD
CY2019	us-gaap	Proceeds From Convertible Debt ProceedsFromConvertibleDebt	0	USD
CY2020	luv	Proceeds From Payroll Support Program Loans And Warrants ProceedsFromPayrollSupportProgramLoansAndWarrants	1016000000	USD
CY2019	luv	Proceeds From Payroll Support Program Loans And Warrants ProceedsFromPayrollSupportProgramLoansAndWarrants	0	USD
CY2018	luv	Proceeds From Payroll Support Program Loans And Warrants ProceedsFromPayrollSupportProgramLoansAndWarrants	0	USD
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	48000000	USD
CY2019	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	40000000	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	35000000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	451000000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	2000000000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	2000000000	USD
CY2020	luv	Reimbursementforairportconstruction Reimbursementforairportconstruction	0	USD
CY2019	luv	Reimbursementforairportconstruction Reimbursementforairportconstruction	0	USD
CY2018	luv	Reimbursementforairportconstruction Reimbursementforairportconstruction	170000000	USD
CY2020	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	839000000	USD
CY2019	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	615000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	342000000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	188000000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	372000000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	332000000	USD
CY2020	luv	Payments Of Terminated Interest Rate Derivative Instruments PaymentsOfTerminatedInterestRateDerivativeInstruments	-59000000	USD
CY2019	luv	Payments Of Terminated Interest Rate Derivative Instruments PaymentsOfTerminatedInterestRateDerivativeInstruments	0	USD
CY2018	luv	Payments Of Terminated Interest Rate Derivative Instruments PaymentsOfTerminatedInterestRateDerivativeInstruments	0	USD
CY2020	luv	Repayments Of Construction Obligation RepaymentsOfConstructionObligation	0	USD
CY2019	luv	Repayments Of Construction Obligation RepaymentsOfConstructionObligation	0	USD
CY2018	luv	Repayments Of Construction Obligation RepaymentsOfConstructionObligation	30000000	USD
CY2020	luv	Capitalized Financing Items CapitalizedFinancingItems	-134000000	USD
CY2019	luv	Capitalized Financing Items CapitalizedFinancingItems	0	USD
CY2018	luv	Capitalized Financing Items CapitalizedFinancingItems	0	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	49000000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-43000000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	3000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	9658000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2990000000	USD
CY2020	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	203000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2496000000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	8515000000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	694000000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	359000000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2548000000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1854000000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1495000000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	11063000000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2548000000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1854000000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	212000000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	88000000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	107000000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	19000000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	779000000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	327000000	USD
CY2020	luv	Assets Constructedfor Others During Period AssetsConstructedforOthersDuringPeriod	145000000	USD
CY2019	luv	Assets Constructedfor Others During Period AssetsConstructedforOthersDuringPeriod	65000000	USD
CY2018	luv	Assets Constructedfor Others During Period AssetsConstructedforOthersDuringPeriod	171000000	USD
CY2020	luv	Supplier Receivables SupplierReceivables	0	USD
CY2019	luv	Supplier Receivables SupplierReceivables	428000000	USD
CY2018	luv	Supplier Receivables SupplierReceivables	0	USD
CY2019	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	177000000	USD
CY2020	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	-32000000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	155000000	USD
CY2020	us-gaap	Advertising Expense AdvertisingExpense	156000000	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	212000000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	215000000	USD
CY2020Q4	luv	Total Employees Who Participated In Extended Emergency Time Off During2020 Who Were Still On Emergency Time Off At December312020 TotalEmployeesWhoParticipatedInExtendedEmergencyTimeOffDuring2020WhoWereStillOnEmergencyTimeOffAtDecember312020	10421	employees
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="text-indent:11.25pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:700;line-height:120%">Concentration Risk</span></div><div style="text-indent:11.25pt"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">Approximately 83 percent of the Company’s full-time equivalent Employees are unionized and are covered by collective-bargaining agreements. A percentage of the Company's unionized Employees, including its Pilots, Flight Attendants, Customer Service Agents, Dispatchers, Aircraft Appearance Technicians, and Meteorologists, which had contracts that became amendable on or before December 31, 2020, are in discussions on labor agreements. Those unionized Employee groups in discussions represent approximately 55 percent of the Company’s full-time equivalent Employees as of December 31, 2020. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">The Company attempts to minimize its concentration risk with regards to its cash, cash equivalents, and its investment portfolio. This is accomplished by diversifying and limiting amounts among different counterparties, the type of investment, and the amount invested in any individual security or money market fund.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">To manage risk associated with financial derivative instruments held, the Company selects and will periodically review counterparties based on credit ratings, limits its exposure to a single counterparty, and monitors the market position of the program and its relative market position with each counterparty. The Company also has agreements with counterparties containing early termination rights and/or bilateral collateral provisions whereby security is required if market risk exposure exceeds a specified threshold amount or credit ratings fall below certain levels. Collateral deposits provided to or held from counterparties serve to decrease, but not totally eliminate, the credit risk associated with the Company’s hedging program. See Note 11 for further information.</span></div><div style="text-align:justify;text-indent:31.5pt"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">As of December 31, 2020, the Company operated an all-Boeing fleet, all of which are variations of the Boeing 737. The Boeing 737 MAX aircraft ("MAX") are crucial to the Company’s growth plans and fleet modernization initiatives. On March 13, 2019, the FAA issued an emergency order for all U.S. airlines to ground the MAX aircraft, including the 34 MAX aircraft in the Company's fleet. On November 18, 2020, the FAA rescinded its order to ground the MAX fleet. The Company is currently working to meet the FAA's requirements by modifying certain operating procedures, implementing enhanced Pilot training requirements, installing FAA-approved flight control software updates, and completing other required maintenance tasks specific to the MAX aircraft. The Company currently estimates that the MAX will return to service on March 11, 2021 after all active Pilots have received updated, MAX-related training. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">The MAX fleet grounding has adversely affected the Company's operating results, and could have a material adverse effect on the Company's operating results in future periods. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">Boeing no longer manufactures versions of the 737 other than the 737 MAX family of aircraft. If the 737 MAX aircraft were to again become unavailable for the Company’s flight operations, the Company’s growth would be restricted unless and until it could procure and operate other types of aircraft from Boeing or another manufacturer, seller, or lessor, and the Company’s operations would be materially adversely affected. In particular, if the Company’s growth were to be dependent upon the introduction of a new aircraft make and model to the Company’s fleet, the Company would need to, among other things, (i) develop and implement new maintenance, operating, and training programs, (ii) secure extensive regulatory approvals, and (iii) implement new technologies. The requirements associated with operating a new aircraft make and model could take an extended period of time to fulfill and would likely impose substantial costs on the Company. A shift away from a single fleet type could also add complexity to the Company’s operations, present operational and compliance risks, and materially increase the Company's costs. Any of these events would have a material, adverse effect on the Company's business, operating results, and financial condition. The Company could also be materially adversely affected if the pricing or operational attributes of its aircraft were to become less competitive. See Note 17 for further information. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">The Company is also dependent on sole or limited suppliers for aircraft engines and certain other aircraft parts and services and would, therefore, also be materially adversely impacted in the event of the unavailability of, inadequate support for, or a mechanical or regulatory issue associated with, engines and other parts.</span></div><div style="text-align:justify;text-indent:31.5pt"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">The Company has historically entered into agreements with some of its co-brand, payment, and loyalty partners that contain exclusivity aspects which place certain confidential restrictions on the Company from entering into certain arrangements with other payment and loyalty partners. Some of these agreements automatically renew on an annual basis, unless either party objects to such extension. None of these agreements are more than 10 years in length. The Company believes the financial benefits generated by the exclusivity aspects of these arrangements outweigh the risks involved with such agreements.</span></div>
CY2020Q4	luv	Percentage Of Employees Represented By Unions Under Collective Bargaining Agreements In Negotiations PercentageOfEmployeesRepresentedByUnionsUnderCollectiveBargainingAgreementsInNegotiations	0.55
CY2020Q4	luv	Number Of Aircraft Grounded Under Emergency Order On March132019 NumberOfAircraftGroundedUnderEmergencyOrderOnMarch132019	34	aircraft
CY2020	luv	Maximum Length Of Agreements With Co Brand Payment And Loyalty Partners MaximumLengthOfAgreementsWithCoBrandPaymentAndLoyaltyPartners	P10Y
CY2020	luv	Cash Raised Net Of Fees CashRaisedNetOfFees	18900000000	USD
CY2020Q4	luv	Proceedsfrom Payroll Support Program Grant ProceedsfromPayrollSupportProgramGrant	3400000000	USD
CY2020Q4	luv	Total Proceeds To Be Provided To Us Airlines From Payroll Support Program Extension Grant Of Consolidated Appropriations Act TotalProceedsToBeProvidedToUSAirlinesFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsAct	15000000000	USD
CY2020Q4	luv	Proceeds From Payroll Support Program Extension Grant Of Consolidated Appropriations Act That Will Be Used To Offset Salaries Wages And Benefits Expenses In1 Q21 ProceedsFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsActThatWillBeUsedToOffsetSalariesWagesAndBenefitsExpensesIn1Q21	1700000000	USD
CY2020Q4	luv	Unsecured Term Loan To Be Issued Through Payroll Support Program Extension Of Consolidated Appropriations Act UnsecuredTermLoanToBeIssuedThroughPayrollSupportProgramExtensionOfConsolidatedAppropriationsAct	259000000	USD
CY2020Q4	luv	Voluntary Separation Program2020 Participants VoluntarySeparationProgram2020Participants	4200	employees
CY2020Q4	luv	Total Employees Who Participated In Extended Emergency Time Off During2020 TotalEmployeesWhoParticipatedInExtendedEmergencyTimeOffDuring2020	11000	employees
CY2020	luv	Costs Incurred For Voluntary Separation Program2020 And Extended Eto CostsIncurredForVoluntarySeparationProgram2020AndExtendedETO	1400000000	USD
CY2020	luv	Proceeds From Payroll Support Program Grant Allocated To Fund Salaries Wages And Benefits ProceedsFromPayrollSupportProgramGrantAllocatedToFundSalariesWagesAndBenefits	2300000000	USD
CY2020	luv	Extended Emergency Time Off Accrual For Employees Who Accepted Through2020 ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThrough2020	620000000	USD
CY2020	luv	Voluntary Separation Program2020 And Extended Emergency Time Off Relieved From Accrual For Employees Who Accepted Through December312020 VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffRelievedFromAccrualForEmployeesWhoAcceptedThroughDecember312020	454000000	USD
CY2020Q4	luv	Voluntary Separation Program2020 And Extended Emergency Time Off Total Accrued VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffTotalAccrued	914000000	USD
CY2020	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	-32000000	USD
CY2020Q4	luv	Number Of Aircraft In Long Term Storage NumberOfAircraftInLongTermStorage	92	aircraft
CY2020Q4	us-gaap	Goodwill Goodwill	970000000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-3074000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	2300000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	2465000000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	565000000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	538000000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	573000000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	0	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1000000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1000000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	565000000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	539000000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	574000000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-5.44
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.28
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.30
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-5.44
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.27
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.29
CY2020Q4	luv	Number Of Aircraft Grounded Under Emergency Order On March132019 NumberOfAircraftGroundedUnderEmergencyOrderOnMarch132019	34	aircraft
CY2020Q4	luv	Property Plant And Equipment Total Number Of Aircraft Expected To Be Leased In4 Q20 And2021 PropertyPlantAndEquipmentTotalNumberOfAircraftExpectedToBeLeasedIn4Q20And2021	16	aircraft
CY2020Q4	luv	Total Capital Commitments Shifting Into Future Periods Associated With Contractual Obligations That Did Not Take Place In2019 Or2020 TotalCapitalCommitmentsShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020	2100000000	USD
CY2020Q4	luv	Capital Commitments From2019 Shifting Into Future Periods Associated With Contractual Obligations That Did Not Take Place In2019 Or2020 CapitalCommitmentsFrom2019ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020	743000000	USD
CY2020Q4	luv	Capital Commitments From2020 Shifting Into Future Periods Associated With Contractual Obligations That Did Not Take Place In2019 Or2020 CapitalCommitmentsFrom2020ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020	1300000000	USD
CY2020Q4	luv	Assets Constructed For Others AssetsConstructedForOthers	309000000	USD
CY2019Q4	luv	Assets Constructed For Others AssetsConstructedForOthers	164000000	USD
CY2020Q4	luv	Air Traffic Liability Passenger Revenueand Ancillary Passenger Services AirTrafficLiabilityPassengerRevenueandAncillaryPassengerServices	2686000000	USD
CY2019Q4	luv	Air Traffic Liability Passenger Revenueand Ancillary Passenger Services AirTrafficLiabilityPassengerRevenueandAncillaryPassengerServices	2125000000	USD
CY2020Q4	luv	Air Traffic Liability Loyalty Program AirTrafficLiabilityLoyaltyProgram	4447000000	USD
CY2019Q4	luv	Air Traffic Liability Loyalty Program AirTrafficLiabilityLoyaltyProgram	3385000000	USD
CY2020Q4	luv	Air Traffic Liability Total AirTrafficLiabilityTotal	7133000000	USD
CY2019Q4	luv	Air Traffic Liability Total AirTrafficLiabilityTotal	5510000000	USD
CY2019Q4	us-gaap	Deferred Revenue DeferredRevenue	3385000000	USD
CY2018Q4	us-gaap	Deferred Revenue DeferredRevenue	3011000000	USD
CY2020	luv	Revenue Amounts Deferred Associated With Points Awarded RevenueAmountsDeferredAssociatedWithPointsAwarded	1958000000	USD
CY2019	luv	Revenue Amounts Deferred Associated With Points Awarded RevenueAmountsDeferredAssociatedWithPointsAwarded	2941000000	USD
CY2020	luv	Passenger Revenue Recognized From Points Redeemed PassengerRevenueRecognizedFromPointsRedeemed	-1003000000	USD
CY2019	luv	Passenger Revenue Recognized From Points Redeemed PassengerRevenueRecognizedFromPointsRedeemed	-2487000000	USD
CY2020	luv	Other Revenue Recognized From Points Redeemed OtherRevenueRecognizedFromPointsRedeemed	-60000000	USD
CY2019	luv	Other Revenue Recognized From Points Redeemed OtherRevenueRecognizedFromPointsRedeemed	-80000000	USD
CY2020	luv	Unused Funds Converted To Loyalty Points UnusedFundsConvertedToLoyaltyPoints	167000000	USD
CY2019	luv	Unused Funds Converted To Loyalty Points UnusedFundsConvertedToLoyaltyPoints	0	USD
CY2020Q4	us-gaap	Deferred Revenue DeferredRevenue	4447000000	USD
CY2019Q4	us-gaap	Deferred Revenue DeferredRevenue	3385000000	USD
CY2019Q4	luv	Air Traffic Liability Total AirTrafficLiabilityTotal	5510000000	USD
CY2020	luv	Air Traffic Liability Current Period Sales AirTrafficLiabilityCurrentPeriodSales	9348000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Maturities Repayments Of Principal In Year Two LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalInYearTwo	524000000	USD
CY2020	luv	Air Traffic Liability Revenueamountsinbeginningbalance AirTrafficLiabilityRevenueamountsinbeginningbalance	-2317000000	USD
CY2020	luv	Air Traffic Liability Revenuefrom Current Period Sales AirTrafficLiabilityRevenuefromCurrentPeriodSales	-5408000000	USD
CY2020Q4	luv	Air Traffic Liability Total AirTrafficLiabilityTotal	7133000000	USD
CY2018Q4	luv	Air Traffic Liability Total AirTrafficLiabilityTotal	5070000000	USD
CY2019	luv	Air Traffic Liability Current Period Sales AirTrafficLiabilityCurrentPeriodSales	21296000000	USD
CY2019	luv	Air Traffic Liability Revenueamountsinbeginningbalance AirTrafficLiabilityRevenueamountsinbeginningbalance	-3816000000	USD
CY2019	luv	Air Traffic Liability Revenuefrom Current Period Sales AirTrafficLiabilityRevenuefromCurrentPeriodSales	-17040000000	USD
CY2019Q4	luv	Air Traffic Liability Total AirTrafficLiabilityTotal	5510000000	USD
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CY2019Q4	luv	Residual Travel Funds ResidualTravelFunds	0.02
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CY2020	luv	Contract With Customer Liability Current Customer Travel Funds Expiration Date As Of December312020 ContractWithCustomerLiabilityCurrentCustomerTravelFundsExpirationDateAsOfDecember312020	2022-09-07
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	542000000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	627000000	USD
CY2020Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	10381000000	USD
CY2019Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	2678000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	220000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	819000000	USD
CY2020Q4	us-gaap	Deferred Finance Costs Gross DeferredFinanceCostsGross	50000000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Gross DeferredFinanceCostsGross	13000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	10111000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	1846000000	USD
CY2020	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	48000000	USD
CY2020	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	5000000	USD
CY2020Q4	luv	Required Minimum Liquidity Levelat All Times After March312021 RequiredMinimumLiquidityLevelatAllTimesAfterMarch312021	1500000000	USD
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CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Repayments Of Principal In Next Twelve Months LongTermDebtAndCapitalLeaseObligationsRepaymentsOfPrincipalInNextTwelveMonths	220000000	USD
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CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Maturities Repayments Of Principal In Year Four LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalInYearFour	152000000	USD
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CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable Current OperatingLeasesFutureMinimumPaymentsReceivableCurrent	41000000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Two Years OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears	17000000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Three Years OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears	7000000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Four Years OperatingLeasesFutureMinimumPaymentsReceivableInFourYears	1000000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1892000000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1349000000	USD
CY2020Q4	luv	Finance Lease Rightof Use Asset Accumulated Depreciation FinanceLeaseRightofUseAssetAccumulatedDepreciation	567000000	USD
CY2019Q4	luv	Finance Lease Rightof Use Asset Accumulated Depreciation FinanceLeaseRightofUseAssetAccumulatedDepreciation	455000000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	667000000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	779000000	USD
CY2020Q4	luv	Lease Rightof Use Asset LeaseRightofUseAsset	2559000000	USD
CY2019Q4	luv	Lease Rightof Use Asset LeaseRightofUseAsset	2128000000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	306000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	353000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	83000000	USD
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	85000000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1562000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	978000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	459000000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	542000000	USD
CY2020Q4	luv	Lease Liability LeaseLiability	2410000000	USD
CY2019Q4	luv	Lease Liability LeaseLiability	1958000000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1000000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	4000000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	1260000000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	1377000000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	113000000	USD
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CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	22000000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	26000000	USD
CY2020	us-gaap	Lease Cost LeaseCost	135000000	USD
CY2019	us-gaap	Lease Cost LeaseCost	142000000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	398000000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	379000000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	22000000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	26000000	USD
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CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	85000000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	915000000	USD
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CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	1000000	USD
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CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P7Y
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P8Y
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CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.037
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.038
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.038
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance Sheet Amount UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount	291000000	USD
CY2020Q4	luv	Lessee Operating Lease Lease Notyet Commenced LesseeOperatingLeaseLeaseNotyetCommenced	9	aircraft
CY2020Q2	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	80500000	shares
CY2020Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.00
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CY2020Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	60000000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	25000000	shares
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	17000000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	55000000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	46000000	USD
CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	29000000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y9M18D
CY2020Q4	luv	Stock Available For Issue Number Employee Stock Purchase Plan StockAvailableForIssueNumberEmployeeStockPurchasePlan	6000000	shares
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CY2019	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	821000	shares
CY2019Q4	luv	Weighted Average Fair Value Of Stock Purchase Right Under Employee Stock Purchase Plan WeightedAverageFairValueOfStockPurchaseRightUnderEmployeeStockPurchasePlan	47.60
CY2019	luv	Aggregate Cost Of Discount Off Market Value For Shares Available Under Employee Stock Purchase Plan AggregateCostOfDiscountOffMarketValueForSharesAvailableUnderEmployeeStockPurchasePlan	5.29	USD
CY2020	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	1386000	shares
CY2020Q4	luv	Weighted Average Fair Value Of Stock Purchase Right Under Employee Stock Purchase Plan WeightedAverageFairValueOfStockPurchaseRightUnderEmployeeStockPurchasePlan	34.39
CY2020	luv	Aggregate Cost Of Discount Off Market Value For Shares Available Under Employee Stock Purchase Plan AggregateCostOfDiscountOffMarketValueForSharesAvailableUnderEmployeeStockPurchasePlan	3.82	USD
CY2020	luv	Discount Percentage Off Market Value For Shares Available Under Employee Stock Purchase Plan DiscountPercentageOffMarketValueForSharesAvailableUnderEmployeeStockPurchasePlan	0.10
CY2020	luv	Percentageofactualconsumptionhedged Percentageofactualconsumptionhedged	0.77
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	134000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	112000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	6000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	6000000	USD
CY2020Q4	us-gaap	Price Risk Cash Flow Hedge Unrealized Gain Loss To Be Reclassified During Next12 Months PriceRiskCashFlowHedgeUnrealizedGainLossToBeReclassifiedDuringNext12Months	-54000000	USD
CY2020Q4	luv	Interest Rate Swap Derivative Aircraft Leases Received In December2020 InterestRateSwapDerivativeAircraftLeasesReceivedInDecember2020	3	aircraft
CY2020Q4	luv	Interest Rate Swap Derivative Aircraft Leases Received In December2020 InterestRateSwapDerivativeAircraftLeasesReceivedInDecember2020	3	aircraft
CY2020	luv	Payments Of Terminated Interest Rate Derivative Instruments PaymentsOfTerminatedInterestRateDerivativeInstruments	-59000000	USD
CY2020Q4	luv	Maximum Sum Of Derivatives Of Counterparty To Be Included In Other MaximumSumOfDerivativesOfCounterpartyToBeIncludedInOther	10000000	USD
CY2020Q4	luv	Cash Collateral Percent Of Fair Value Fuel Derivatives Contracts CashCollateralPercentOfFairValueFuelDerivativesContracts	1
CY2020Q4	luv	Letterof Credit Percentof Collateral LetterofCreditPercentofCollateral	1
CY2020Q4	us-gaap	Time Deposits TimeDeposits	425000000	USD
CY2019	luv	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Gain Loss Includedin Other Comprehensive Income Loss Total FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisGainLossIncludedinOtherComprehensiveIncomeLossTotal	-112000000	USD
CY2020	luv	Debt Instrument Agreements Not Publicly Held DebtInstrumentAgreementsNotPubliclyHeld	4	Agreements
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	561000000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1200000000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1000000000.0	USD
CY2020	luv	Defined Contribution Pension Plans Maximum Age Requirement For Paying Medical And Dental Premiums With Accrued Unused Sick Time DefinedContributionPensionPlansMaximumAgeRequirementForPayingMedicalAndDentalPremiumsWithAccruedUnusedSickTime	P65Y
CY2019Q4	us-gaap	Defined Benefit Plan Benefit Obligation DefinedBenefitPlanBenefitObligation	288000000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Benefit Obligation DefinedBenefitPlanBenefitObligation	232000000	USD
CY2020	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	22000000	USD
CY2019	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	17000000	USD
CY2020	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	10000000	USD
CY2019	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	10000000	USD
CY2020	us-gaap	Defined Benefit Plan Benefit Obligation Benefits Paid DefinedBenefitPlanBenefitObligationBenefitsPaid	10000000	USD
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CY2019	us-gaap	Defined Benefit Plan Curtailments DefinedBenefitPlanCurtailments	0	USD
CY2020	us-gaap	Defined Benefit Plan Special Termination Benefits DefinedBenefitPlanSpecialTerminationBenefits	2000000	USD
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CY2020Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Year Five DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive	26000000	USD
CY2020Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Five Fiscal Years Thereafter DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter	146000000	USD
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CY2020Q4	luv	Number Of Aircraft Grounded Under Emergency Order On March132019 NumberOfAircraftGroundedUnderEmergencyOrderOnMarch132019	34	aircraft
CY2020Q4	luv	After Tax Potential Concessionsand Other Considerations Announced July2019 AfterTaxPotentialConcessionsandOtherConsiderationsAnnouncedJuly2019	4900000000	USD
CY2020Q4	luv	Pre Tax Potential Concessionsand Other Considerations Announced January2020 PreTaxPotentialConcessionsandOtherConsiderationsAnnouncedJanuary2020	2600000000	USD
CY2020Q4	luv	Number Of Aircraft Grounded Under Emergency Order On March132019 NumberOfAircraftGroundedUnderEmergencyOrderOnMarch132019	34	aircraft
CY2020Q4	luv	Numberof Aircraft Not Delivered Dueto Grounding Under Emergency Order NumberofAircraftNotDeliveredDuetoGroundingUnderEmergencyOrder	41	aircraft
CY2020	luv	Supplier Proceeds SupplierProceeds	428000000	USD
CY2020Q1	us-gaap	Revenues Revenues	4234000000	USD
CY2020Q2	us-gaap	Revenues Revenues	1008000000	USD
CY2020Q3	us-gaap	Revenues Revenues	1793000000	USD
CY2020Q4	us-gaap	Revenues Revenues	2013000000	USD
CY2020Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	-110000000	USD
CY2020Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	-1127000000	USD
CY2020Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	-1411000000	USD
CY2020Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	-1169000000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-144000000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-1239000000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-1542000000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-1331000000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	-94000000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-915000000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	-1157000000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	-908000000	USD
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.18
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.63
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.96
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.54
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.18
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.63
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.96
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.54
CY2019Q1	us-gaap	Revenues Revenues	5149000000	USD
CY2019Q2	us-gaap	Revenues Revenues	5909000000	USD
CY2019Q3	us-gaap	Revenues Revenues	5639000000	USD
CY2019Q4	us-gaap	Revenues Revenues	5729000000	USD
CY2019Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	505000000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	968000000	USD
CY2019Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	819000000	USD
CY2019Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	665000000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	504000000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	968000000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	819000000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	666000000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	387000000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	741000000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	659000000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	514000000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.70
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.37
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.24
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.98
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.37
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.23
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.98
CY2019Q4	luv	Discretionary Profitsharingrelatedto Impactof Aircraft Grounded Under Emergency Order DiscretionaryProfitsharingrelatedtoImpactofAircraftGroundedUnderEmergencyOrder	124000000	USD
CY2019Q4	luv	Net Income Impactof2019 Discretionary Profitsharing NetIncomeImpactof2019DiscretionaryProfitsharing	97000000	USD
CY2019Q4	luv	Net Incomeper Share Impactof2019 Discretionary Profitsharing NetIncomeperShareImpactof2019DiscretionaryProfitsharing	0.18

Files In Submission

Name	View Source	Status
0000092380-21-000033-index-headers.html	Edgar Link	pending
0000092380-21-000033-index.html	Edgar Link	pending
0000092380-21-000033.txt	Edgar Link	pending
0000092380-21-000033-xbrl.zip	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
luv-12312020ex23.htm	Edgar Link	pending
luv-12312020xex1013a.htm	Edgar Link	pending
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luv-20201231_cal.xml	Edgar Link	unprocessable
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luv-20201231_g1.jpg	Edgar Link	pending
luv-20201231_g2.jpg	Edgar Link	pending
luv-20201231_htm.xml	Edgar Link	completed
luv-20201231_lab.xml	Edgar Link	unprocessable
luv-20201231_pre.xml	Edgar Link	unprocessable
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$LUV
SOUTHWEST AIRLINES CO Stock $luv

2020 Q4 Form 10-K Financial Statement

#000009238021000033 Filed on February 08, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$LUV SOUTHWEST AIRLINES CO Stock $luv

2020 Q4 Form 10-K Financial Statement

#000009238021000033 Filed on February 08, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$LUV
SOUTHWEST AIRLINES CO Stock $luv