OPERATING SEGMENT INFORMATION, ASSETS (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Total assets	$ 14,813	$ 14,613
Alaska Airlines [Member]
Total assets	20,140	19,937
Horizon [Member]
Total assets	1,382	1,352
Consolidating and Other [Member]
Total assets	$ (6,709)	$ (6,676)

Amount of asset recognized for present right to economic benefit.

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+ Details