INCOME TAXES (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

Deferred tax (assets) and liabilities comprise the following (in millions):

	2021		2020
Excess of tax over book depreciation	$	1,145	$	1,126
Intangibles - net	19		15
Operating lease assets	351		342
Other - net	76		106
Deferred tax liabilities	1,591		1,589
Mileage Plan	(416)		(385)
Inventory obsolescence	(17)		(17)
Employee benefits	(127)		(215)
Net operating losses	(25)		(27)
Operating lease liabilities	(374)		(381)
Leasehold maintenance	(40)		(73)
Other - net	(34)		(103)
Deferred tax assets	(1,033)		(1,201)
Valuation allowance	20		19
Net deferred tax liabilities	$	578	$	407

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

The components of income tax expense (benefit) are as follows (in millions): 

	2021		2020		2019
Current income tax expense (benefit):
Federal	$	40	$	(212)	$	26
State	16		(11)		13
Total current income tax expense (benefit)	56		(223)		39
Deferred income tax expense (benefit):
Federal	80		(246)		175
State	15		(47)		33
Total deferred income tax expense (benefit)	95		(293)		208
Income tax expense (benefit)	$	151	$	(516)	$	247

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	2021			2020			2019
Income (loss) before income tax	$	629		$	(1,840)		$	1,016
Expected tax expense (benefit)	132			(386)			213
Nondeductible expenses	10			9			9
State income taxes	20			(62)			36
Tax law changes	(14)			(93)			(9)
Valuation allowance	1			18			—
Other - net	2			(2)			(2)
Actual tax expense (benefit)	$	151		$	(516)		$	247
Effective tax rate	24.0		%	28.0		%	24.3		%

Summary of Income Tax Contingencies [Table Text Block]

The Company has identified its federal tax return and its state tax returns in Alaska, Oregon and California as “major” tax jurisdictions.  A summary of the Company's jurisdictions and the periods that are subject to examination are as follows:

Jurisdiction	Period
Federal	2007 to 2020
Alaska	2015 to 2020
California	2007 to 2020
Oregon	2003 to 2020

Certain tax years are open to the extent of net operating loss carryforwards.

Changes in the liability for gross unrecognized tax benefits during 2021, 2020 and 2019 are as follows (in millions):

	2021		2020		2019
Balance at January 1,	$	35	$	40	$	40
Additions related to prior years	3		1		—
Releases related to prior years	—		(1)		(1)
Additions related to current year activity	3		—		2
Releases due to settlements	—		(4)		—
Releases due to lapse of statute of limitations	—		(1)		(1)
Balance at December 31,	$	41	$	35	$	40