OPERATING SEGMENT INFORMATION, ASSETS (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Total assets	$ 13,882	$ 14,046
Alaska Airlines [Member]
Total assets	19,161	19,754
Horizon [Member]
Total assets	1,251	1,170
Consolidating and Other [Member]
Total assets	$ (6,530)	$ (6,878)

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details