EMPLOYEE BENEFIT PLANS - Asset Allocation (Details)	Dec. 31, 2025	Dec. 31, 2024
Qualified Defined Benefit Plan - Salaried \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	100.00%	100.00%
Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	100.00%	100.00%
Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	100.00%	100.00%
Equity securities \| Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	56.00%	52.00%
Domestic equity securities \| Qualified Defined Benefit Plan - Salaried \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	0.00%
Actual Allocations	0.00%	0.00%
Domestic equity securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	27.00%	34.00%
Non-U.S. equity securities \| Qualified Defined Benefit Plan - Salaried \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	0.00%
Actual Allocations	0.00%	0.00%
Non-U.S. equity securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	12.00%	13.00%
Fixed income securities \| Qualified Defined Benefit Plan - Salaried \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	100.00%
Actual Allocations	100.00%	100.00%
Fixed income securities \| Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	44.00%	44.00%
Fixed income securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	58.00%	50.00%
Real estate \| Qualified Defined Benefit Plan - Salaried \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	0.00%
Actual Allocations	0.00%	0.00%
Real estate \| Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	0.00%
Actual Allocations	0.00%	4.00%
Real estate \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Actual Allocations	3.00%	3.00%
Minimum \| Equity securities \| Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	50.00%
Minimum \| Domestic equity securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	6.00%
Minimum \| Non-U.S. equity securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	0.00%
Minimum \| Fixed income securities \| Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	40.00%
Minimum \| Fixed income securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	47.00%
Minimum \| Real estate \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	0.00%
Maximum \| Equity securities \| Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	60.00%
Maximum \| Domestic equity securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	35.00%
Maximum \| Non-U.S. equity securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	18.00%
Maximum \| Fixed income securities \| Qualified Defined Benefit Plan - Salaried \| Hawaiian Holdings, Inc.
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	50.00%
Maximum \| Fixed income securities \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	85.00%
Maximum \| Real estate \| Pension Plan \| Alaska Air Group
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	10.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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