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Fair Value Measurements - Additional Information (Details) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2019 USD ($) engine | Jun. 30, 2018 USD ($) | Dec. 31, 2018 USD ($)
Fair Value Disclosures [Abstract] |  |  |
Fair value of notes receivable | $ 30,900,000 |  | $ 200,000
Fair value of notes payable | 1,265,000,000.0 |  | 1,348,100,000
Derivative [Line Items] |  |  |
Increase in interest expense | (400,000) | $ (100,000) |
Increase (decrease) in asset write-down | $ 4,400,000 | $ 3,600,000 |
Number of engines | engine | 4 |  |
Number of assets impaired | engine | 3 |  |
Interest rate contract |  |  |
Derivative [Line Items] |  |  |
Notional amount outstanding | $ 100,000,000.0 |  | 100,000,000
Notional amount, liability | $ 22,000 |  |
Assets at fair value |  |  | $ 1,700,000

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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