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v3.20.4

Overview (Details) employee in Thousands |  |  |  |  | 1 Months Ended | 2 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 28, 2020 USD ($) | Jul. 02, 2020 USD ($) | Apr. 21, 2020 USD ($) | Apr. 20, 2020 USD ($) | Jul. 31, 2020 employee | Feb. 25, 2021 USD ($) | Mar. 31, 2021 | Dec. 31, 2020 USD ($) employee | Sep. 30, 2020 USD ($) | Jun. 30, 2020 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2020 USD ($) employee | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Feb. 15, 2021 USD ($) | Jan. 15, 2021 USD ($)
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  |  |  |  |  |  |  | $ (1,897,000,000) | $ (1,841,000,000) | $ (1,627,000,000) | $ (1,704,000,000) | $ 641,000,000 | $ 1,024,000,000 | $ 1,052,000,000 | $ 292,000,000 | $ (7,069,000,000) | $ 3,009,000,000 | $ 2,122,000,000 |  |
Percent of capacity cut |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 57.00% |  |  |  |
Rolling cancellation period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 60 days |  |  |  |
Proceeds from issuance of debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 16,044,000,000 | 1,847,000,000 | 1,594,000,000 |  |
Proceeds from the issuance of common stock |  |  | $ 1,100,000,000 |  |  |  |  |  |  |  |  |  |  |  |  | 2,100,000,000 |  |  |  |
Payroll taxes deferred under the CARES Act |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 199,000,000 |  |  |  |
Number of employees notified of plans for workforce reduction | employee |  |  |  |  | 36 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of employee furloughs | employee |  |  |  |  |  |  |  | 13 |  |  |  |  |  |  |  | 13 |  |  |  |
Number of employees subject to voluntary options | employee |  |  |  |  |  |  |  | 9 |  |  |  |  |  |  |  | 9 |  |  |  |
Total funding provided under the Payroll Support Program |  |  |  | $ 5,100,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Funding provided through direct grants under the Payroll Support Program |  |  |  | 3,600,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Funding provided through loans under the Payroll Support Program |  |  |  | $ 1,500,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash received under the Payroll Support Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,100,000,000 |  |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total funding provided under the Payroll Support Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,600,000,000
Funding provided through direct grants under the Payroll Support Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,900,000,000
Cash received under the Payroll Support Program |  |  |  |  |  | $ 1,300,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent of capacity cut |  |  |  |  |  |  | 51.00% |  |  |  |  |  |  |  |  |  |  |  |  |
CARES Act Credit Agreement | Line of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit agreement |  |  |  |  |  |  |  | $ 7,500,000,000 |  |  |  |  |  |  |  | 7,500,000,000 |  |  |  |
Notes, Secured Term Loans and Aircraft Financing |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 13,400,000,000 |  |  |  |
Unsecured Debt | PSP Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Debt | PSP2 Note | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Funding provided through loans under the Payroll Support Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 753,000,000 |
Term of debt |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit | CARES Act Credit Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of debt | $ 520,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit agreement | $ 7,500,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
CEO and President |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Voluntary pay reduction |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |
Non-Employee Directors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Voluntary pay reduction |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |
United Airlines, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (7,067,000,000) | 3,011,000,000 | 2,123,000,000 |  |
Proceeds from issuance of debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 16,044,000,000 | $ 1,847,000,000 | $ 1,594,000,000 |  |
United Airlines, Inc. | Secured Debt | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from lines of credit |  | $ 1,000,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000,000.0 |  |  |  |
Credit agreement |  |  |  |  |  |  |  | $ 2,000,000,000.0 |  |  |  |  |  |  |  | $ 2,000,000,000.0 |  |  |  |

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