VARIABLE INTEREST ENTITIES - Statements of Operations of VIEs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Variable Interest Entity [Line Items]
Revenue	$ 373,676	$ 357,467	$ 725,785	$ 726,865
Net loss	(31,396)	(30,107)	(87,142)	(71,179)
Bristow Aviation Holdings Limited
Variable Interest Entity [Line Items]
Revenue	321,956	310,325	623,926	628,779
Operating loss	(2,978)	(20,773)	(22,632)	(40,516)
Net loss	$ (62,081)	$ (80,794)	$ (141,250)	$ (169,337)