Carrying amount as of the balance sheet date of obligations due all related parties.

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RELATED PARTIES (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
RELATED PARTIES (Details) - USD ($) $ in Thousands	Jan. 31, 2016	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Related party note receivable interest rate	1.80%
Affiliated entity, common ownership
Related Party Transaction [Line Items]
Expenses with related parties		$ 0	$ 8	$ 0	$ 29
Affiliated entity, family member
Related Party Transaction [Line Items]
Expenses with related parties		100	100	100	100
Senior executive
Related Party Transaction [Line Items]
Note receivable from related party	$ 5,000					$ 100
Commercial cooperation agreement
Related Party Transaction [Line Items]
Expenses with related parties		1,400	600	3,200	2,800
Payable to related parties		4,300		4,300		$ 3,000
Discounted flights to affiliates
Related Party Transaction [Line Items]
Revenue from related parties		400	500	1,600	1,400
Aircraft leased \| Stockholder
Related Party Transaction [Line Items]
Expenses with related parties		200		300
Consultation services on employee benefits
Related Party Transaction [Line Items]
Expenses with related parties		$ 23	$ 23	$ 69	$ 23