Vessels, Net (Details) - USD ($)	3 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Mar. 31, 2017
Accumulated depreciation
Vessels, net	$ 1,587,588,137		$ 1,603,469,247
Vessels
Cost
Balance at the beginning of the period	1,728,769,295
Other additions	218,685
Balance at the end of the period	1,728,987,980
Accumulated depreciation
Balance at the beginning of the period	(125,300,048)
Impairment	0	$ 0
Depreciation	(16,099,795)
Balance at the end of the period	(141,399,843)
Mortgaged VLGC vessels, carrying value	$ 1,587,600,000		$ 1,603,500,000