ACQUISITION OF HAWAIIAN HOLDINGS, INC. - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	12 Months Ended
	Sep. 18, 2024	Dec. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2024
Business Acquisition [Line Items]
Revenue			$ 11,735	$ 10,426	$ 9,646
Net loss			(395)	(235)	(58)
Goodwill		$ 2,724	2,724	1,943
Hawaiian Holdings, Inc.
Business Acquisition [Line Items]
Multiplied by cash consideration for each share of common stock per the merger agreement (in dollars per share)	$ 18.00
Cash consideration paid for common stock issued and outstanding	$ 936
Outstanding voting shares acquired (in percent)	100.00%
Cash consideration paid for settlement of equity awards and change in control payments	$ 41
Total purchase consideration	977
Revenue		869
Net loss		113
Goodwill		$ 781	781	1,900	$ 2,700	$ 761
Merger-related costs			$ 208
Hawaiian Holdings, Inc. | Acquisition-related Costs
Business Acquisition [Line Items]
Net loss				$ 227
Hawaiian Holdings, Inc. | Slots
Business Acquisition [Line Items]
Indefinite-lived intangible assets	$ 2