CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
NET CASH PROVIDED BY OPERATING ACTIVITIES	$ 171,023	$ 157,648
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of marketable securities	(349,334)	(337,694)
Sales of marketable securities	351,614	383,282
Acquisition of property and equipment:
Aircraft and rotable spare parts	(64,857)	(33,525)
Buildings and ground equipment	(8,453)	(4,250)
Proceeds from the sale of property and equipment	118	2,212
Deposits on aircraft	(5,140)
Decrease (increase) in other assets, net	9,943	(10,579)
NET CASH USED IN INVESTING ACTIVITIES	(66,109)	(554)
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal payments on long-term debt	(113,672)	(111,158)
Net proceeds from issuance of common stock	1,293	1,446
Employee income tax paid on vested equity awards	(27,242)	(6,930)
Purchase of treasury stock	(13,682)	(8,750)
NET CASH USED IN FINANCING ACTIVITIES	(153,303)	(125,392)
Increase (decrease) in cash and cash equivalents	(48,389)	31,702
Cash and cash equivalents at beginning of period	227,362	148,277
CASH AND CASH EQUIVALENTS AT END OF PERIOD	178,973	179,979
Non-cash investing and financing activities:
Acquisition of property and equipment	45,606	6,575
Cash paid (refunded) during the period for:
Interest, net of capitalized amounts	27,637	30,362
Income taxes, net of refunds	$ (18)	$ 42