BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($) segment	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| segment	1
Allowance for obsolescence	$ 739	$ 689
Obsolescence expense	175	102	$ 73
Carrying value of computer software	456	453
Amortization expense	32	37	41
Projected amortization expense in 2025	28
Projected amortization expense in 2026	18
Projected amortization expense in 2027	11
Projected amortization expense in 2028	10
Projected amortization expense in 2029	8
Advertising expense	235	221	165
Computer software
Summary Of Significant Accounting Policies [Line Items]
Depreciation expense	$ 155	$ 168	$ 166

Summary Of Significant Accounting Policies [Line Items]

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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The amount of the valuation account as of the balance sheet date which reduces the carrying amount of airline related inventory (including expendable merchandise, goods, commodities, or supplies to be used primarily in air transport of passengers or freight) to net realizable value; takes into consideration such factors as market value, excessive quantities based on expected sales, technological obsolescence, and shrinkage.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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