XML 112 R37.htm IDEA: XBRL DOCUMENT
v3.25.2

Comprehensive Income (Loss) - Schedule of AOCI Components (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2025
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Balance at beginning of period | $ 9,365 | $ 10,350
Deferred tax impact, beginning balance | 8 | 8
Changes in fair value | (40) | (69)
Reclassification to earnings | 29 | 59
Changes in fair value, deferred tax impact | 12 | 21
Reclassification to earnings, deferred tax impact | 9 | 18
Deferred tax impact, ending balance | 11 | 11
Balance at end of period | 8,000 | 8,000
Accumulated other comprehensive income (loss) |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Balance at beginning of period | (24) | (25)
Balance at end of period | (35) | (35)
Fuel derivatives |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Balance at beginning of period | (193) | (193)
Changes in fair value | (52) | (90)
Reclassification to earnings | 36 | 74
Balance at end of period | (209) | (209)
Defined benefit plan items |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Balance at beginning of period | 167 | 167
Changes in fair value | 0 | 0
Reclassification to earnings | 0 | 0
Balance at end of period | 167 | 167
Other |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Balance at beginning of period | (6) | (7)
Changes in fair value | 0 | 0
Reclassification to earnings | 2 | 3
Balance at end of period | $ (4) | $ (4)

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_AOCIAttributableToParentNetOfTaxRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) attributable to parent. + References No definition available. + Details
Name: | us-gaap_AociTaxAttributableToParent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 55 -Paragraph 15 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482739/220-10-55-15 + Details
Name: | us-gaap_OciBeforeReclassificationsNetOfTaxAttributableToParent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 12 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-12 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482765/220-10-50-4 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(19)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 55 -Paragraph 15 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482739/220-10-55-15 + Details
Name: | us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 12 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-12 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482765/220-10-50-4 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(19)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 17A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-17A + Details
Name: | us-gaap_ReclassificationFromAociCurrentPeriodTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(i)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(31)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 852 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481372/852-10-55-10 Reference 8: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 830 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479168/946-830-55-12 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(19)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.6-05(4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-2 Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(4)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-3 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-3 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-3 Reference 14: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 15: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481687/323-10-50-3 Reference 16: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 4.E) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480418/310-10-S99-2 + Details
Name: | us-gaap_StockholdersEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedOtherComprehensiveIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=luv_AccumulatedOtherAdjustmentsAttributableToParentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |