Debt Instrument, Issuance Price, Percentage

No definition available.

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- Definition

Debt Instrument, Quarterly Installment Percentage

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Variable Rate Floor

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Period Type:	instant

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Debt - Narrative (Details) - USD ($)		9 Months Ended
Debt - Narrative (Details) - USD ($)	Apr. 21, 2021	Sep. 30, 2021	Aug. 31, 2021
Debt Instrument [Line Items]
Unamortized debt discount		$ 558,000,000
PSP2 Note \| Unsecured Debt
Debt Instrument [Line Items]
Face amount		$ 870,000,000
Term of debt		10 years
PSP2 Note \| Years 1 through 5 \| Unsecured Debt
Debt Instrument [Line Items]
Stated interest rate		1.00%
PSP2 Note \| Years 6 through 10 \| Unsecured Debt \| SOFR
Debt Instrument [Line Items]
Percent spread on variable rate		2.00%
PSP3 Note \| Unsecured Debt
Debt Instrument [Line Items]
Face amount		$ 810,000,000
Term of debt		10 years
PSP3 Note \| Years 1 through 5 \| Unsecured Debt
Debt Instrument [Line Items]
Stated interest rate		1.00%
PSP3 Note \| Years 6 through 10 \| Unsecured Debt \| SOFR
Debt Instrument [Line Items]
Percent spread on variable rate		2.00%
2026 Notes and 2029 Notes \| Secured Debt
Debt Instrument [Line Items]
Face amount	$ 4,000,000,000	$ 4,000,000,000
2026 Notes \| Secured Debt
Debt Instrument [Line Items]
Face amount	$ 2,000,000,000	$ 2,000,000,000
Stated interest rate	4.375%	4.375%
Issuance price as a percent of principal amount	100.00%
2029 Notes \| Secured Debt
Debt Instrument [Line Items]
Face amount	$ 2,000,000,000	$ 2,000,000,000
Stated interest rate	4.625%	4.625%
Issuance price as a percent of principal amount	100.00%
Term Loan B Facility due 2028 \| Secured Debt
Debt Instrument [Line Items]
Face amount	$ 5,000,000,000	$ 5,000,000,000
Quarterly installment repayment as a percent of the original principal amount	0.25%
Term Loan B Facility due 2028 \| Secured Debt \| LIBOR
Debt Instrument [Line Items]
Percent spread on variable rate	3.75%
Interest rate floor	0.75%
Term Loan Facility \| Secured Debt
Debt Instrument [Line Items]
Face amount	$ 1,400,000,000	1,400,000,000
CARES Act Term Loan Facility \| Secured Debt
Debt Instrument [Line Items]
Face amount	520,000,000	520,000,000
Special Facility Revenue Bonds \| Secured Debt
Debt Instrument [Line Items]
Face amount			$ 289,000,000
Stated interest rate			4.00%
Revolving Credit Facility \| Senior Secured Revolving Credit Facility due 2025 \| Secured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,750,000,000	1,750,000,000
Commitment fee percentage	0.75%
Revolving Credit Facility \| Senior Secured Revolving Credit Facility due 2025 \| Secured Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Percent spread on variable rate	3.00%
Revolving Credit Facility \| Senior Secured Revolving Credit Facility due 2025 \| Secured Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Percent spread on variable rate	3.50%
Revolving Credit Facility \| Credit Agreement \| Secured Debt
Debt Instrument [Line Items]
Face amount	$ 1,000,000,000	1,000,000,000
Revolving Credit Facility \| United Airlines, Inc. \| Secured Debt
Debt Instrument [Line Items]
Available under revolving credit facility		1,750,000,000
Aggregate principal amount outstanding		$ 0