GOODWILL AND INTANGIBLE ASSETS - Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Accumulated Amortization	$ 16	$ 0
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Gross Carrying Value	889	90
Accumulated Amortization	16	0
Hawaiian Trademark
Indefinite-Lived Intangible Assets [Line Items]
Gross Carrying Value	390	0
Slots
Indefinite-Lived Intangible Assets [Line Items]
Gross Carrying Value	92	90
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	285	0
Accumulated Amortization	5	0
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Accumulated Amortization	5	0
Co-brand Partnerships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	122	0
Accumulated Amortization	11	0
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Accumulated Amortization	$ 11	$ 0

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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