FINANCIAL DERIVATIVE INSTRUMENTS - Fair Values by Balance Sheet Location (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Fuel derivative contracts \| Prepaid expenses and other current assets
Derivatives, Fair Value
Gross amounts of recognized assets	$ 22	$ 86
Gross amounts offset in the balance sheet	4	15
Cash collateral deposits held from counterparties for fuel contracts - current	4	15
Fuel derivative contracts \| Other assets
Derivatives, Fair Value
Gross amounts of recognized assets	108	137
Gross amounts offset in the balance sheet	18	35
Cash collateral deposits held from counterparties for fuel contracts - current	18	35
Fuel derivative contracts \| Accounts and other receivables
Derivatives, Fair Value
Receivable from third parties for fuel contracts	1	12
Designated as Hedging Instrument
Derivatives, Fair Value
Gross amounts of recognized assets	130	223
Gross amounts offset in the balance sheet	0	0
Designated as Hedging Instrument \| Fuel derivative contracts \| Prepaid expenses and other current assets
Derivatives, Fair Value
Gross amounts of recognized assets	22	86
Gross amounts offset in the balance sheet	0	0
Designated as Hedging Instrument \| Fuel derivative contracts \| Other assets
Derivatives, Fair Value
Gross amounts of recognized assets	108	137
Gross amounts offset in the balance sheet	$ 0	$ 0

Derivative, Cash Receivable (Payable) On Hedge

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- Definition

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

+ References

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-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-SubTopic 10
-Topic 815
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-Subparagraph (b)
-SubTopic 20
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483466/210-20-50-3

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- Definition

Fair value, before effects of master netting arrangements, of a 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. 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
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Subparagraph (c)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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-Topic 210
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-Name Accounting Standards Codification
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-SubTopic 20
-Topic 860
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481326/860-20-50-4D

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ 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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