AIRCRAFT - Aircraft Fleet (Details) - aircraft		3 Months Ended
	Mar. 29, 2023	Mar. 31, 2023	Mar. 31, 2022
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		54	48
Additions	3	3	2
Reclassifications		0	0
Removals		0	0
Balance at end of period		57	50
Passenger
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		42	36
Additions		0	2
Reclassifications		0	0
Removals		0	0
Balance at end of period		42	38
Passenger | Owned
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		29	21
Additions		0	1
Reclassifications		0	0
Removals		0	0
Balance at end of period		29	22
Passenger | Finance leases
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		11	9
Additions		0	1
Reclassifications		0	2
Removals		0	0
Balance at end of period		11	12
Passenger | Operating leases
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		2	6
Additions		0	0
Reclassifications		0	(2)
Removals		0	0
Balance at end of period		2	4
Cargo | Aircraft Operated for Amazon
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		12	12
Additions		0	0
Reclassifications		0	0
Removals		0	0
Balance at end of period		12	12
Other Aircraft | Aircraft Held for Operating Lease
Movement in Property, Plant and Equipment [Roll Forward]
Balance at beginning of period		0
Additions		3
Reclassifications		0
Removals		0
Balance at end of period		3