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Related Party Transactions (Details) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Jan. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) engine aircraft. | Sep. 30, 2018 USD ($) engine
Sale of Vehicle | Chief Executive Officer |  |  |
Related Party Transaction [Line Items] |  |  |
Related party transaction amount | $ 0.1 |  |
Use of Marine Vessel | Chief Executive Officer |  |  |
Related Party Transaction [Line Items] |  |  |
Related party transaction amount |  | $ 0.2 |
WMES |  |  |
Related Party Transaction [Line Items] |  |  |
Number of aircrafts sold | aircraft. |  | 5 |
Proceeds from sale of aircraft |  | $ 76.4 |
Proceeds from sale of engines |  |  | $ 23.2
Number of engines sold | engine |  |  | 2
Willis Aeronautical Services, Inc. |  |  |
Related Party Transaction [Line Items] |  |  |
Proceeds from sale of engines |  | $ 2.6 | $ 2.6
Number of engines sold | engine |  | 1 | 1

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- Definition 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. + References No definition available. + Details
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