Flight Equipment held for sale (Details) - Aircraft Held For Sale $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2019 USD ($) aircraft	Dec. 31, 2019 aircraft	Dec. 31, 2018 USD ($) aircraft
Flight Equipment Held for Sale
Number of aircraft sold or agreed to be sold \| aircraft	3	3	6
Flight Equipment, Net \| $	$ 106.0		$ 241.6

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