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- Definition

Equity Securities, Restructuring Agreement, Maximum Investment

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- Definition

Fair Value [Line Items]

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Percentage of ownership of equity interest excluding interest in entity that is consolidated and equity method investee.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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- Definition

Amount of investment in equity security without readily determinable fair value.

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- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Number of aircraft operated by the carrier.

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No definition available.

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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FAIR VALUE MEASUREMENTS, INVESTMENTS AND NOTES RECEIVABLE - Narrative (Details) $ in Millions		6 Months Ended
	May 28, 2025 USD ($)	Jun. 30, 2025 USD ($) aircraft	Apr. 04, 2025
Fair Value [Line Items]
Equity method investments		$ 255
Carrying amount of loan receivable		$ 74
Republic Airways
Fair Value [Line Items]
Number of aircraft operated \| aircraft		66
Champlain Enterprises LLC
Fair Value [Line Items]
Number of aircraft operated \| aircraft		59
Republic Airways
Fair Value [Line Items]
Ownership stake		19.00%
CommuteAir
Fair Value [Line Items]
Ownership stake		40.00%
United Airlines Ventures Sustainable Flight Fund
Fair Value [Line Items]
Ownership stake		33.00%
Other Equity Investments
Fair Value [Line Items]
Investment carrying amount		$ 283
New Surviving Entity \| Scenario, Plan \| Maximum
Fair Value [Line Items]
Equity interests exchanged for commitment to facilitate merger transaction			6.00%
Mesa
Fair Value [Line Items]
Variable interest		10.00%
Azul
Fair Value [Line Items]
Potential equity investments in connection with reorganization process	$ 300
Corporate debt
Fair Value [Line Items]
Available-for-sale securities remaining maturities		2 years