XML 56 R38.htm IDEA: XBRL DOCUMENT
v3.21.2

Financial Derivative Instruments - Fair Values of Fuel Derivatives Amounts Posted as Collateral (Details) $ in Millions | Jun. 30, 2021 USD ($)
--- | ---
If credit rating is non-investment grade, fair value of fuel derivative level at which: |
Maximum sum of derivatives of counterparty to be included in other | $ 9
Letter of credit substitution percentage | 100.00%
Cash collateral percentage | 100.00%
Fuel derivatives |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | $ 502
Cash collateral held from CP | 120
Fuel derivatives | Counterparty A |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 119
Cash collateral held from CP | 120
Fuel derivatives | Counterparty A | Minimum |
If credit rating is investment grade, fair value of fuel derivative level at which: |
Cash is provided to CP | (100)
Cash is received from CP | 0
Fuel derivatives | Counterparty B |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 58
Cash collateral held from CP | 0
Fuel derivatives | Counterparty B | Minimum |
If credit rating is investment grade, fair value of fuel derivative level at which: |
Cash is provided to CP | (50)
Cash is received from CP | 150
Fuel derivatives | Counterparty C |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 122
Cash collateral held from CP | 0
Fuel derivatives | Counterparty C | Minimum |
If credit rating is investment grade, fair value of fuel derivative level at which: |
Cash is provided to CP | (75)
Cash is received from CP | 250
Fuel derivatives | Counterparty D |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 57
Cash collateral held from CP | 0
Fuel derivatives | Counterparty D | Minimum |
If credit rating is investment grade, fair value of fuel derivative level at which: |
Cash is provided to CP | (125)
Cash is received from CP | 125
Fuel derivatives | Counterparty E |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 59
Cash collateral held from CP | 0
Fuel derivatives | Counterparty E | Minimum |
If credit rating is investment grade, fair value of fuel derivative level at which: |
Cash is provided to CP | (40)
Cash is received from CP | 100
Fuel derivatives | Counterparty F |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 41
Cash collateral held from CP | 0
Fuel derivatives | Counterparty F | Minimum |
If credit rating is investment grade, fair value of fuel derivative level at which: |
Cash is provided to CP | (65)
Cash is received from CP | 70
Fuel derivatives | Counterparty G |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 36
Cash collateral held from CP | 0
Fuel derivatives | Counterparty G | Minimum |
If credit rating is investment grade, fair value of fuel derivative level at which: |
Cash is provided to CP | (100)
Cash is received from CP | 100
Fuel derivatives | Counterparty Other |
Schedule Of Fair Values Of Fuel Derivatives Amounts Posted As Collateral And Collateral Posting Thresholds [Line Items] |
Fair value of fuel derivatives | 10
Cash collateral held from CP | $ 0

X
- Definition Represents percentage of cash collateral provided on the fair value of fuel derivative contracts when credit rating is non-investment grade. + References No definition available. + Details
Name: | luv_CashCollateralPercentOfFairValueFuelDerivativesContracts
Namespace Prefix: | luv_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | luv_InvestmentGradeCreditRatingAbstract
Namespace Prefix: | luv_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Investment Grade Rating Fair Value Of Fuel Derivative Level In Which Cash Is Received + References No definition available. + Details
Name: | luv_InvestmentGradeRatingFairValueOfFuelDerivativeLevelInWhichCashIsReceived
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Investment Grade Rating Fair Value Of Fuel Derivative Levels In Which Cash Is Provided Threshold 1 + References No definition available. + Details
Name: | luv_InvestmentGradeRatingFairValueOfFuelDerivativeLevelsInWhichCashIsProvidedThreshold1
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Letter Of Credit Percent Of Collateral + References No definition available. + Details
Name: | luv_LetterOfCreditPercentOfCollateral
Namespace Prefix: | luv_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Maximum sum of derivatives of a counterparty to be included in Other and no risk of the Company posting collateral. + References No definition available. + Details
Name: | luv_MaximumSumOfDerivativesOfCounterpartyToBeIncludedInOther
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | luv_NonInvestmentGradeCreditRatingAbstract
Namespace Prefix: | luv_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | luv_ScheduleOfFairValuesOfFuelDerivativesAmountsPostedAsCollateralAndCollateralPostingThresholdsLineItems
Namespace Prefix: | luv_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959 + Details
Name: | us-gaap_CollateralAlreadyPostedAggregateFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226006-175313 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=125515794&loc=d3e41678-113959 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CommodityContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyAlphaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyDMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyEMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyFMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyGMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=luv_CounterpartyOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |