The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Number of aircraft operated by the carrier.

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The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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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.

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Represents the number of engines in lease portfolio of equity method investee.

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Number Of Aircrafts Sold

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Related Party Transaction Proceeds from Sale of Aircraft

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Investments - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) engine	Jun. 30, 2020 USD ($) aircraft.	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($) engine aircraft.
Schedule of Equity Method Investments [Line Items]
Maintenance reserve revenue	$ 29,986	$ 26,475			$ 50,514	$ 51,825
Number of engines sold \| engine			0			0
WMES
Schedule of Equity Method Investments [Line Items]
Ownership interest	50.00%		50.00%	50.00%	50.00%
Number of engines in lease portfolio \| engine			36
Number of aircraft in lease portfolio \| aircraft.				5
Net book value of equipment held for operating lease	$ 299,600		$ 299,600	$ 299,600	$ 299,600
Number of aircrafts sold \| aircraft.				0		5
Proceeds from sale of aircraft						$ 75,500
Number of engines sold			0	0
CASC Willis
Schedule of Equity Method Investments [Line Items]
Ownership interest	50.00%		50.00%	50.00%	50.00%
Number of engines in lease portfolio \| engine			4
Net book value of equipment held for operating lease	$ 47,500		$ 47,500	$ 47,500	$ 47,500
Number of aircrafts sold \| aircraft.				0		0
Number of engines sold \| engine			0			0
Other Income \| WMES \| Asset Management
Schedule of Equity Method Investments [Line Items]
Maintenance reserve revenue	$ 300	$ 600			$ 800	$ 1,100