LEASES - Schedule of Leased Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lessee, Lease, Description [Line Items]
Operating Lease, Right-of-Use Asset	$ 1,195	$ 1,471
Operating Lease, Expense	690	708	$ 654
Sublease Income	(15)	(15)	(16)
Lease, Cost	675	693	638
Aircraft Leases [Member]
Lessee, Lease, Description [Line Items]
Operating Lease, Right-of-Use Asset	468	701
Operating Lease, Cost	100	191	174
CPA Aircraft [Member]
Lessee, Lease, Description [Line Items]
Operating Lease, Right-of-Use Asset	622	683
Operating Lease, Cost	108	100	80
Airport Facilities [Member]
Lessee, Lease, Description [Line Items]
Operating Lease, Right-of-Use Asset	29	21
Operating Lease, Cost	451	384	379
Corporate real estate [Member]
Lessee, Lease, Description [Line Items]
Operating Lease, Right-of-Use Asset	76	66
Operating Lease, Cost	$ 31	$ 33	$ 21