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Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Decrease from divestiture			$ (7,379)
Impairment charge			(30,945)
Amortization of intangible assets			17,504	$ 19,317	$ 16,017
Aviation
Goodwill [Line Items]
Decrease from divestiture		$ (7,400)	(7,379)
Impairment charge	$ (30,900)		$ (30,945)
Aviation \| CT Aerospace LLC
Goodwill [Line Items]
Impairment charge	$ (2,800)