CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
OPERATING ACTIVITIES:
Net income		$ 76.2	$ 64.6	$ 54.8
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization		126.3	117.0	159.4
Deferred income taxes		33.9	17.2	29.3
Stock-based compensation expense		20.2	1.0	1.5
Changes in certain assets and liabilities, net of effects of the Merger:
Inventories	[1]	0.4	(2.1)	4.6
NET CASH PROVIDED BY OPERATING ACTIVITIES		322.0	226.1	329.2
INVESTING ACTIVITIES:
Purchase of property and equipment	[1]	(396.9)	(226.7)	(378.1)
Proceeds from insurance, sale of property, and other equipment		0.7	86.1	133.5
Pre-delivery deposits paid	[1]	(13.8)	(32.9)	(13.5)
Cash acquired in connection with the Merger		22.8	0.0	0.0
Purchases of marketable securities and investments		(176.2)	(187.3)	(282.8)
Proceeds from the sale of marketable securities		212.5	255.3	120.0
NET CASH USED IN INVESTING ACTIVITIES		(350.9)	(105.5)	(420.9)
FINANCING ACTIVITIES:
Proceeds from issuance of debt		299.4	177.3	476.6
Payments on debt and finance lease obligations		(231.6)	(240.1)	(260.1)
Payments on early debt extinguishment		0.0	(37.4)	(101.0)
Payments for U.S. Treasury Warrant redemption		(1.1)	0.0	0.0
Taxes paid for the net share settlement of restricted stock units		(9.1)	0.0	(0.2)
Other, net		(2.9)	(2.0)	(8.2)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES		54.7	(102.2)	107.1
NET CHANGES IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH		25.8	18.4	15.4
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH—Beginning of period		131.9	113.5	98.1
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH—End of period		157.7	131.9	113.5
CASH PAID FOR:
Interest, net of capitalized amounts		58.8	56.0	44.4
Income taxes, net of refunds		2.8	5.7	3.3
SUPPLEMENTAL DISCLOSURE OF NON-CASH TRANSACTIONS:
Non-cash Merger purchase consideration (Note 3)		120.2	0.0	0.0
Property and equipment acquired, but not paid		13.4	7.6	15.0
Parts credits used from aircraft and engine manufacturers		0.0	0.5	0.0
Nonrelated Party
Adjustments to reconcile net income to net cash from operating activities:
Other, net		8.3	11.9	18.6
Changes in certain assets and liabilities, net of effects of the Merger:
Receivables		30.5	(2.5)	(0.2)
Other assets		(15.8)	(10.9)	(3.8)
Accounts payable and other current liabilities		(9.9)	25.1	32.8
Other non-current liabilities		0.2	5.0	3.4
SUPPLEMENTAL DISCLOSURE OF NON-CASH TRANSACTIONS:
Parts credits received from aircraft and engine manufacturers		6.1	4.0	6.7
Related Party
Adjustments to reconcile net income to net cash from operating activities:
Other, net		(2.4)	(6.1)	(18.5)
Changes in certain assets and liabilities, net of effects of the Merger:
Receivables		(38.0)	(8.4)	55.5
Other assets		(1.6)	(20.6)	(8.2)
Accounts payable and other current liabilities		29.9	(0.9)	(0.8)
Other non-current liabilities		63.8	35.8	0.8
SUPPLEMENTAL DISCLOSURE OF NON-CASH TRANSACTIONS:
Parts credits received from aircraft and engine manufacturers		$ 1.4	$ 0.5	$ 1.4

[1] The Company made net aircraft, pre-delivery deposit payments, and inventory and rotable spare part purchases from its original equipment manufacturer, a related party, of $289.7 million, $168.2 million, and $294.8 million during the years ended December 31, 2025, 2024, and 2023, respectively.