AIRCRAFT - Aircraft Fleet (Details) - aircraft	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period	63	60
Additions	3	3
Reclassifications	0	0
Removals	0	0
Balance at end of period	66	63
Passenger
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period	45	42
Additions	0	2
Reclassifications	0	0
Removals	0	0
Balance at end of period	45	44
Passenger | Owned
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period	34	29
Additions	0	1
Reclassifications	0	0
Removals	0	0
Balance at end of period	34	30
Passenger | Finance leases
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period	11	13
Additions	0	1
Reclassifications	0	0
Removals	0	0
Balance at end of period	11	14
Cargo | Aircrafts Operated For Amazon
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period	12	12
Additions	3	0
Reclassifications	0	0
Removals	0	0
Balance at end of period	15	12
Other Property | Owned Aircraft Held for Operating Lease
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period	4
Additions	0
Reclassifications	0
Removals	0
Balance at end of period	4
Other Property | Owned Aircraft Held for Operating Lease
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		5
Additions		0
Reclassifications		0
Removals		0
Balance at end of period		5
Other Property | Subleased Aircraft
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period	2	1
Additions	0	1
Reclassifications	0	0
Removals	0	0
Balance at end of period	2	2