SEGMENT INFORMATION - Restructuring (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
General and administrative	$ 4,388	$ 3,551	$ 9,051	$ 7,735
Aviation Leasing | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Operating expenses		3,467		10,093
General and administrative		0		0
Acquisition and transaction expenses		970		1,948
Corporate and Other | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Operating expenses		3,166		6,707
General and administrative		3,551		7,735
Acquisition and transaction expenses		1,338		1,834
Previously Reported | Aviation Leasing | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Operating expenses		2,721		8,799
General and administrative		0		0
Acquisition and transaction expenses		0		13
Previously Reported | Corporate and Other | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Operating expenses		3,166		6,707
General and administrative		4,297		9,029
Acquisition and transaction expenses		2,308		3,769
Restatement Adjustment | Aviation Leasing | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Operating expenses		746		1,294
General and administrative		0		0
Acquisition and transaction expenses		970		1,935
Restatement Adjustment | Corporate and Other | Other Restructuring
Restructuring Cost and Reserve [Line Items]
Operating expenses		0		0
General and administrative		(746)		(1,294)
Acquisition and transaction expenses		$ (970)		$ (1,935)