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

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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Debt - Narrative (Details) - USD ($)	1 Months Ended
Debt - Narrative (Details) - USD ($)	May 31, 2019	Feb. 28, 2019	Sep. 30, 2019
United Airlines, Inc. \| Pass-Through Certificates
Debt Instrument [Line Items]
Aggregate principal amount			$ 2,234,000,000
Revolving Credit Facility \| United Airlines, Inc. \| Secured Debt
Debt Instrument [Line Items]
Available under revolving credit facility			$ 2,000,000,000.0
2019-1 Pass Through Certificates \| United Airlines, Inc. \| Pass-Through Certificates
Debt Instrument [Line Items]
Proceeds from issuance of debt		$ 93,000,000
4.875% Senior Notes due 2025 \| Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount	$ 350,000,000
Interest rate	4.875%
Redemption price rate	101.00%