DEBT - Narrative (Details) - USD ($)	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Aug. 07, 2025
Debt Instrument [Line Items]
Weighted-average interest rate (in percent)	4.80%
Debt instrument, increase (decrease)	$ 69,000,000
Long-term debt payments	(236,000,000)	$ (149,000,000)
Other Debt Obligations
Debt Instrument [Line Items]
Debt instrument, face amount	237,000,000
Other Debt Obligations | Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount	168,000,000
Other Debt Obligations | Secured Debt | Subsequent Event
Debt Instrument [Line Items]
Debt instrument, face amount			$ 154,000,000
Alaskan And Hawaiian Credit Facility | Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, borrowing capacity	850,000,000
Outstanding borrowing	0
Alaskan Credit Facility | Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, borrowing capacity	106,000,000
Interest rate swap agreements | Cash Flow Hedging | Derivative Instruments Designated as Hedges
Debt Instrument [Line Items]
Notional amount	$ 535,000,000