Available for Sale Investment Maturity Term

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- Definition

Equity Securities, Ownership Percentage

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- Definition

Equity Securities Without Readily Determinable Fair Value, Ownership Interest

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Fair Value [Line Items]

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Financing Receivable, Stated Interest Rate

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- Definition

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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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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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.

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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- Definition

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

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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- Definition

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

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- Definition

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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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Financial Instruments and Fair Value Measurements - Narrative (Details) $ in Millions	6 Months Ended
	Jun. 30, 2021 USD ($) aircraft shares	Nov. 30, 2020 USD ($)
Fair Value [Line Items]
Equity method investments	$ 152
Notes receivable	120
Notes receivable, fair value	$ 41
Class A Clear Warrants
Fair Value [Line Items]
Number of securities called by warrants (in shares) \| shares	2,400,000
Archer Warrants
Fair Value [Line Items]
Number of securities called by warrants (in shares) \| shares	4,700,000
Boom Warrants
Fair Value [Line Items]
Number of securities called by warrants (in shares) \| shares	568,857
Carrying value of warrants	$ 17
Republic
Fair Value [Line Items]
Number of aircraft operated \| aircraft	66
Champlain
Fair Value [Line Items]
Number of aircraft operated \| aircraft	70
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	9 years
Corporate Debt \| Maximum
Fair Value [Line Items]
Available-for-sale securities remaining maturities	2 years
U.S. Government and Agency Notes
Fair Value [Line Items]
Available-for-sale securities remaining maturities	1 year
Azul
Fair Value [Line Items]
Equity stake in Azul	2.00%
Carrying value of investment	$ 238
Azul \| Preferred Stock
Fair Value [Line Items]
Equity stake in Azul	8.00%
Clear Secure, Inc.
Fair Value [Line Items]
Carrying value of investment	$ 31
Republic
Fair Value [Line Items]
Equity method investment, ownership percentage	19.00%
ManaAir
Fair Value [Line Items]
Equity method investment, ownership percentage	49.90%
Champlain
Fair Value [Line Items]
Equity method investment, ownership percentage	40.00%
Fulcrum BioEnergy Inc.
Fair Value [Line Items]
Other investment ownership Interest	6.00%
Investment carrying value	$ 51
Fulcrum BioEnergy Inc. \| Preferred Stock
Fair Value [Line Items]
Other investment ownership Interest	7.00%
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	$ 170