CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
OPERATING REVENUES:
Total operating revenues	$ 867,118	$ 725,643	$ 1,670,732	$ 1,417,474
OPERATING EXPENSES:
Salaries, wages and benefits	355,005	322,441	706,004	657,642
Aircraft maintenance, materials and repairs	183,267	162,491	328,682	304,717
Depreciation and amortization	96,814	97,169	192,684	191,318
Aircraft fuel	21,328	18,279	42,492	39,243
Airport-related expenses	17,535	16,955	38,423	35,250
Aircraft rentals	1,310	2,428	2,586	21,956
Other operating expenses	72,219	74,020	140,715	140,192
Total operating expenses	747,478	693,783	1,451,586	1,390,318
OPERATING INCOME	119,640	31,860	219,146	27,156
OTHER INCOME (EXPENSE):
Interest income	12,040	10,494	23,666	20,527
Interest expense	(28,966)	(33,718)	(58,795)	(67,338)
Other income (loss), net	(548)	9,001	(1,676)	11,175
Total other expense, net	(17,474)	(14,223)	(36,805)	(35,636)
INCOME (LOSS) BEFORE INCOME TAXES	102,166	17,637	182,341	(8,480)
PROVISION (BENEFIT) FOR INCOME TAXES	26,588	2,218	46,465	(1,828)
NET INCOME (LOSS)	$ 75,578	$ 15,419	$ 135,876	$ (6,652)
BASIC EARNINGS (LOSS) PER SHARE (in dollars per share)	$ 1.88	$ 0.35	$ 3.38	$ (0.14)
DILUTED EARNINGS (LOSS) PER SHARE (in dollars per share)	$ 1.82	$ 0.35	$ 3.28	$ (0.14)
Weighted average common shares:
Basic (in shares)	40,179	43,837	40,239	46,614
Diluted (in shares)	41,431	44,219	41,462	46,614
COMPREHENSIVE INCOME (LOSS):
Net income (loss)	$ 75,578	$ 15,419	$ 135,876	$ (6,652)
Net unrealized appreciation (depreciation) on marketable securities, net of taxes	(660)	1,514	(833)	2,994
TOTAL COMPREHENSIVE INCOME (LOSS)	74,918	16,933	135,043	(3,658)
Flying agreements
OPERATING REVENUES:
Total operating revenues	838,170	700,394	1,616,459	1,364,232
Lease, airport services and other
OPERATING REVENUES:
Total operating revenues	$ 28,948	$ 25,249	$ 54,273	$ 53,242