Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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- Definition

Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

+ References

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- 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.

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- Definition

Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e689-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section 45
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-URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e637-108580

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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Financial Derivative Instruments - (Gain) Loss by Hedging Relationship (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021
Fuel derivative contracts
Derivative Instruments, (Gain) Loss
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Other (gains) losses, net	Other (gains) losses, net
Cash Flow Hedging
Derivative Instruments, (Gain) Loss
(Gain) Loss recognized in AOCI on derivatives, net of tax	$ (508)	$ (463)
Cash Flow Hedging \| Fuel derivative contracts
Derivative Instruments, (Gain) Loss
(Gain) Loss recognized in AOCI on derivatives, net of tax	(494)	(461)
Cash Flow Hedging \| Interest rate derivatives
Derivative Instruments, (Gain) Loss
(Gain) Loss recognized in AOCI on derivatives, net of tax	$ (14)	$ (2)
Not Designated as Hedging Instrument \| Fuel derivative contracts
Derivative Instruments, (Gain) Loss
(Gain) Loss recognized in income on derivatives			$ (41)	$ (13)