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Fair Value Measurements - Additional Information (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 USD ($) engine | Mar. 31, 2018 USD ($) | Dec. 31, 2018 USD ($)
Fair Value Disclosures [Abstract] |  |  |
Fair value of notes receivable | $ 31,100,000 |  | $ 200,000
Fair value of notes payable | 1,333,600,000 |  | 1,348,100,000
Increase in interest expense | (200,000) | $ 24,000 |
Increase (decrease) in asset write-down | $ 1,100,000 | $ 0 |
Number of engines | engine | 2 |  |
Interest rate contract |  |  |
Derivative [Line Items] |  |  |
Notional amount outstanding | $ 100,000,000 |  | 100,000,000
Assets at fair value | $ 1,000,000 |  | $ 1,700,000

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