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Fair Value Measurements - Additional Information (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) airframe equipment | Mar. 31, 2020 USD ($) engine | Dec. 31, 2020 USD ($)
Derivative [Line Items] |  |  |
Fair value of notes receivable | $ 201,300,000 |  | $ 159,200,000
Fair value of notes payable | 1,757,100,000 |  | 1,691,000,000.0
Increase in interest expense | 900,000 | $ 36,000.0 |
Asset write-down | $ 1,900,000 | $ 2,100,000 |
Number of assets impaired | 1 | 3 |
Remaining book value | $ 44,600,000 |  |
Number of assets previously impaired | equipment | 22 |  |
Interest rate contract |  |  |
Derivative [Line Items] |  |  |
Net fair value of swap liability | $ 2,500,000 |  | $ (4,000,000.0)
Fair value of interest rate swap, asset | 4,900,000 |  |
Fair value of interest rate swap, liability | $ 2,300,000 |  |

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