PROPERTY AND EQUIPMENT, ASSETS HELD FOR SALE AND OEM COST RECOVERIES Capital Expenditures (Details) $ in Thousands	12 Months Ended
	Mar. 31, 2019 USD ($) aircraft	Mar. 31, 2018 USD ($) aircraft	Mar. 31, 2017 USD ($) aircraft
Property and equipment [Line Items]
Number Of aircraft added | aircraft	1	5	9
Payments to Acquire Productive Assets	$ 40,902	$ 46,287	$ 135,110
Aircraft
Property and equipment [Line Items]
Payments to Acquire Productive Assets	35,315	32,418	127,447
Other Capitalized Property Plant and Equipment
Property and equipment [Line Items]
Payments to Acquire Productive Assets	$ 5,587	13,869	7,663
Construction in progress
Property and equipment [Line Items]
Payments to Acquire Productive Assets		$ 2,300	$ 71,400
Medium Aircraft
Property and equipment [Line Items]
Number Of aircraft added | aircraft	1	5	5
SAR Aircraft
Property and equipment [Line Items]
Number Of aircraft added | aircraft	0	0	4