Investments (Details) - Blackbird - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Nov. 04, 2014
Investments
Percentage of equity ownership				9.50%
Gain (loss) on sale of aircraft	$ (0.3)	$ 0.8
Due from affiliate	0.6		$ 0.7
Equity method investment	$ 30.8		$ 25.1

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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