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- Definition

Fair Value [Line Items]

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Financing Receivable, Stated Interest Rate

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- Definition

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Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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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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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.

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

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Amount, before allowance for credit loss, of financing receivable.

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Number of aircraft operated by the carrier.

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The principal amount of the receivable or note before consideration of the discount or premium.

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Financial Instruments and Fair Value Measurements - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021 USD ($) aircraft	Nov. 30, 2020 USD ($)
Fair Value [Line Items]
Equity method investments	$ 160
Champlain
Fair Value [Line Items]
Number of aircraft operated \| aircraft	78
Republic
Fair Value [Line Items]
Number of aircraft operated \| aircraft	66
Corporate Debt \| Maximum
Fair Value [Line Items]
Available-for-sale securities remaining maturities	2 years
Asset-Backed Securities \| Minimum
Fair Value [Line Items]
Available-for-sale securities remaining maturities	1 year
Asset-Backed Securities \| Maximum
Fair Value [Line Items]
Available-for-sale securities remaining maturities	8 years
U.S. Government and Agency Notes
Fair Value [Line Items]
Available-for-sale securities remaining maturities	1 year
Champlain
Fair Value [Line Items]
Equity method investment, ownership percentage	40.00%
Republic
Fair Value [Line Items]
Equity method investment, ownership percentage	19.00%
ManaAir
Fair Value [Line Items]
Equity method investment, ownership percentage	49.90%
Other Investment
Fair Value [Line Items]
Investment carrying value	$ 79
Kingsland \| Standby Letters of Credit
Fair Value [Line Items]
Cash collateral for a standby letter of credit	$ 217	$ 217
Avianca Holdings S.A. (“AVH”) \| DIP Loan \| United Airlines, Inc.
Fair Value [Line Items]
Interest rate	14.50%
Loan balance	$ 176
Boom Technology, Inc.
Fair Value [Line Items]
Notes receivable	120
Notes receivable, carrying value	$ 44