v3.25.4

LEASES - Narrative (Details) $ in Billions	12 Months Ended
LEASES - Narrative (Details) $ in Billions	Dec. 31, 2025 USD ($) aircraft	Nov. 30, 2024 USD ($)
Lessee, Lease, Description [Line Items]
Number of aircraft leases under various sale-leaseback transactions	63
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Current maturities of long-term debt, finance leases, and other financial liabilities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt, finance leases, and other financial liabilities
Lease terms of additional leases that have not yet commenced (up to)	28 years
Operating And Financing Leases, Lease Not Yet Commenced
Lessee, Lease, Description [Line Items]
Amount of leases that have not yet commenced \| $	$ 6.6
SFRB \| City Of Houston, Texas
Lessee, Lease, Description [Line Items]
Indebtedness incurred \| $		$ 1.1
Maximum
Lessee, Lease, Description [Line Items]
Term of sale-leaseback transactions	11 years
Maximum \| SFRB \| City Of Houston, Texas
Lessee, Lease, Description [Line Items]
Interest rate		5.50%
Minimum
Lessee, Lease, Description [Line Items]
Term of sale-leaseback transactions	7 years
Minimum \| SFRB \| City Of Houston, Texas
Lessee, Lease, Description [Line Items]
Interest rate		5.25%
Mainline Aircraft
Lessee, Lease, Description [Line Items]
Number of aircraft subject to operating leases	81
Number of aircraft subject to finance leases	27
Mainline Aircraft \| Maximum
Lessee, Lease, Description [Line Items]
Term of operating leases	12 years
Regional Aircraft
Lessee, Lease, Description [Line Items]
Number of aircraft subject to operating leases	217
Number of aircraft subject to finance leases	11
Non-Aircraft \| Maximum
Lessee, Lease, Description [Line Items]
Term of operating leases	32 years
Non-Aircraft \| Minimum
Lessee, Lease, Description [Line Items]
Term of operating leases	1 month

Lessee, Operating And Finance Lease, Not Yet Commenced, Term Of Contract

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Lessee, Operating And Finance Leases, Term Of Contract

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Number Of Aircraft Subject To Finance Leases

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Number Of Aircraft Subject To Operating Leases

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- Definition

Sale-Leaseback Transaction, Number Of Aircraft Leases

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Indicates line item in statement of financial position that includes current finance lease liability.

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Lease term for sale and leaseback transaction, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of unrecorded obligation to transfer funds in future for fixed or minimum amount or quantity of product and service at fixed or minimum price. Includes, but is not limited to, lease not yet commenced and take-or-pay and throughput contracts.

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United Airlines Holdings, Inc. 10-K