Available for Sale Investment Maturity Term

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- Definition

Equity Securities, Ownership Percentage

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- Definition

Fair Value [Line Items]

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- Definition

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

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

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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- Definition

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

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Financial Instruments and Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Nov. 30, 2020
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%
Gain (loss) on equity securities	$ (23)	$ 293
Carrying value of investment	$ 182
Azul \| Preferred Stock
Fair Value [Line Items]
Equity stake in Azul	8.00%
Kingsland \| Standby Letters of Credit
Fair Value [Line Items]
Cash collateral for a standby letter of credit			$ 217
Avianca Holdings S.A. (“AVH”) \| DIP Loan \| United Airlines, Inc.
Fair Value [Line Items]
Interest rate	14.50%
Loan balance	$ 164