Condensed Consolidated Statements of Operations - USD ($)	2 Months Ended	3 Months Ended		7 Months Ended	9 Months Ended
	Mar. 12, 2025	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Operating revenues:
Total operating revenues	$ 755,354,000	$ 958,524,000	$ 1,197,104,000	$ 2,235,402,000	$ 3,743,530,000
Operating expenses:
Salaries, wages and benefits	308,585,000	367,356,000	427,125,000	810,929,000	1,276,986,000
Aircraft fuel	219,922,000	253,308,000	373,399,000	574,591,000	1,187,046,000
Aircraft rent	120,183,000	154,064,000	148,511,000	325,641,000	389,056,000
Landing fees and other rents	87,001,000	104,900,000	130,044,000	227,301,000	352,826,000
Depreciation and amortization	54,853,000	58,032,000	84,028,000	132,515,000	249,860,000
Maintenance, materials and repairs	47,498,000	54,849,000	57,368,000	114,805,000	164,736,000
Distribution	39,461,000	45,833,000	55,687,000	103,404,000	146,786,000
Special charges (credits)	0	0	151,000	(4,000)	36,028,000
Loss (gain) on disposal of assets	11,655,000	(113,713,000)	3,191,000	(114,041,000)	(13,885,000)
Other operating	153,395,000	168,810,000	214,039,000	381,256,000	610,379,000
Total operating expenses	1,042,553,000	1,093,439,000	1,493,543,000	2,556,397,000	4,399,818,000
Operating income (loss)	(287,199,000)	(134,915,000)	(296,439,000)	(320,995,000)	(656,288,000)
Other (income) expense:
Interest expense	47,682,000	46,261,000	54,135,000	118,141,000	163,251,000
Loss (gain) on extinguishment of debt	(87,000)	2,728,000	0	2,728,000	(14,996,000)
Capitalized interest	(956,000)	(393,000)	(1,173,000)	(1,068,000)	(16,865,000)
Interest income	(8,873,000)	(7,001,000)	(11,341,000)	(16,146,000)	(37,100,000)
Other (income) expense	902,000	337,000	(23,000)	649,000	(65,848,000)
Special charges, non-operating	5,511,000	13,026,000	0	25,441,000	0
Reorganization (gain) expense	(421,464,000)	125,983,000	0	125,983,000	0
Total other (income) expense	(377,285,000)	180,941,000	41,598,000	255,728,000	28,442,000
Income (loss) before income taxes	90,086,000	(315,856,000)	(338,037,000)	(576,723,000)	(684,730,000)
Provision (benefit) for income taxes	17,870,000	1,620,000	(29,794,000)	(2,480,000)	(40,925,000)
Net income (loss)	$ 72,216,000	$ (317,476,000)	$ (308,243,000)	$ (574,243,000)	$ (643,805,000)
Basic earnings (loss) per share (in dollars per share)	$ 0.66	$ (7.87)	$ (2.81)	$ (16.17)	$ (5.88)
Diluted earnings (loss) per share (in dollars per share)	$ 0.66	$ (7.87)	$ (2.81)	$ (16.17)	$ (5.88)
Passenger
Operating revenues:
Total operating revenues	$ 740,610,000	$ 937,126,000	$ 1,171,405,000	$ 2,190,891,000	$ 3,664,518,000
Other
Operating revenues:
Total operating revenues	$ 14,744,000	$ 21,398,000	$ 25,699,000	$ 44,511,000	$ 79,012,000