OPERATING SEGMENT INFORMATION (Tables) - USD ($)
$ in Millions

3 Months Ended

Mar. 31, 2023

Mar. 31, 2022

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment

Operating segment information is as follows (in millions):

	Three Months Ended March 31, 2023
	Mainline		Regional		Horizon		Consolidating & Other(a)		Air Group Adjusted(b)			Special Items(c)		Consolidated
Operating Revenue
Passenger revenue	$	1,690	$	294	$	—	$	—	$	1,984		$	—	$	1,984
CPA revenue	—		—		78		(78)		—			—		—
Mileage Plan other revenue	143		11		—		—		154			—		154
Cargo and other revenue	57		—		—		1		58			—		58
Total Operating Revenue	1,890		305		78		(77)		2,196			—		2,196
Operating Expenses
Operating expenses, excluding fuel	1,390		256		84		(77)		1,653			64		1,717
Fuel expense	561		85		—		(1)		645			20		665
Total Operating Expenses	1,951		341		84		(78)		2,298			84		2,382
Non-operating Income (Expense)	(6)		—		(8)		1		(13)			—		(13)
Income (Loss) Before Income Tax	$	(67)	$	(36)	$	(14)	$	2	$	(115)		$	(84)	$	(199)
Pretax Margin									(5.2)		%			(9.1)		%
	Three Months Ended March 31, 2022
	Mainline		Regional		Horizon		Consolidating & Other(a)		Air Group Adjusted(b)			Special Items(c)		Consolidated
Operating Revenue
Passenger revenue	$	1,243	$	268	$	—	$	—	$	1,511		$	—	$	1,511
CPA revenue	—		—		94		(94)		—			—		—
Mileage Plan other revenue	100		12		—		—		112			—		112
Cargo and other revenue	57		—		—		1		58			—		58
Total Operating Revenue	1,400		280		94		(93)		1,681			—		1,681
Operating Expenses
Operating expenses, excluding fuel	1,194		262		99		(94)		1,461			75		1,536
Fuel expense	381		73		—		—		454			(107)		347
Total Operating Expenses	1,575		335		99		(94)		1,915			(32)		1,883
Non-operating Income (Expense)	1		—		(5)		—		(4)			—		(4)
Income (Loss) Before Income Tax	$	(174)	$	(55)	$	(10)	$	1	$	(238)		$	32	$	(206)
Pretax Margin									(14.2)		%			(12.3)		%

(a)Includes consolidating entries, Air Group parent company, McGee Air Services, and other immaterial business units.

(b)The Air Group Adjusted column represents the financial information that is reviewed by management to assess performance of operations and determine capital allocation and excludes certain charges.

(c)Includes special items and mark-to-market fuel hedge accounting adjustments.

Total assets were as follows (in millions):

	March 31, 2023		December 31, 2022
Mainline	$	19,896	$	19,733
Horizon	1,158		1,157
Consolidating & Other	(6,758)		(6,704)
Consolidated	$	14,296	$	14,186

Nonoperating Income (Expense)

$ (13)

$ (4)

Interest income

17

7

Operating Expenses, Excluding Fuel

1,717

1,536

Economic fuel

665

347

Operating Expenses

2,382

1,883

Income (Loss) Before Income Tax

$ (199)

$ (206)

Pretax Margin, GAAP

(9.10%)

(12.30%)

Pretax Margin, Adjusted

(5.20%)

(14.20%)