REVENUE - Significant Categories of Operating Revenues (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
REVENUE
Total Operating Revenues	$ 338,366	$ 326,649
Passenger
REVENUE
Total Operating Revenues	285,259	285,888
Scheduled Service
REVENUE
Total Operating Revenues	146,551	143,522
Charter
REVENUE
Total Operating Revenues	57,245	54,692
Ancillary
REVENUE
Total Operating Revenues	81,463	87,674
Cargo
REVENUE
Total Operating Revenues	46,089	28,157
Other
REVENUE
Total Operating Revenues	$ 7,018	$ 12,604