Debt - Contractual Principal Payments (Details) - UAL And United $ in Millions	Jun. 30, 2023 USD ($)
Debt Instrument [Line Items]
Last six months of 2023	$ 1,451
2024	3,965
2025	3,450
2026	5,244
2027	2,468
After 2027	14,044
Total long-term debt	$ 30,622

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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+ Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details