Vessels, Net (Details)	6 Months Ended
	Sep. 30, 2019 USD ($) item	Mar. 31, 2019 USD ($)
Vessels, Net
Vessels, net	$ 1,453,476,869	$ 1,478,520,314
Accumulated depreciation
Number of VLGCs with scrubber purchase commitments | item	10
Vessels
Cost
Balance at the beginning of the period	$ 1,732,993,810
Other additions	7,362,978
Balance at the end of the period	1,740,356,788
Accumulated depreciation
Balance at the beginning of the period	(254,473,496)
Impairment	0
Depreciation	(32,406,423)
Balance at the end of the period	$ (286,879,919)
Number of VLGCs with scrubber purchase commitments | item	10
Mortgaged VLGC vessels, carrying value	$ 1,453,500,000	$ 1,478,500,000