LEASES - Rent payment deferrals (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
LEASES
Aircraft Lease Payment Deferrals	$ 0	$ 7,569
Finance leases
LEASES
Aircraft Lease Payment Deferrals	2,133
Operating leases
LEASES
Aircraft Lease Payment Deferrals	$ 5,436

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