COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands		6 Months Ended
	Dec. 21, 2018 USD ($) item	Dec. 31, 2018 USD ($) item	Sep. 30, 2019 USD ($)	Apr. 15, 2019 USD ($)	Feb. 28, 2019 USD ($)	Sep. 30, 2018 USD ($)
Purchase commitment
Vessel assets		$ 1,344,870	$ 1,290,741
Secured Debt | $495 Million Credit Facility
Purchase commitment
Maximum borrowing capacity		$ 495,000	495,000	$ 495,000	$ 495,000	$ 495,000
Purchase Agreements for BWTS
Purchase commitment
Number of vessels to receive ballast water treatments systems | item		43
Vessel assets		$ 1,804	11,286
Purchase Agreement of BWTS for Capesize Vessels
Purchase commitment
BWTS purchase price		800
Purchase Agreement of BWTS for Panamax Vessels
Purchase commitment
BWTS purchase price		500
Purchase Agreement of BWTS for Supramax Vessels
Purchase commitment
BWTS purchase price		500
Purchase Agreement of BWTS for Handysize Vessels
Purchase commitment
BWTS purchase price		500
Scrubber Installation Agreements
Purchase commitment
Number of Capesize vessels to receive scrubber installations | item	17
Cost of scrubber installation per vessel	$ 2,250
Vessel assets		$ 428	$ 32,156