Leases (assets and liabilities) (Details)	3 Months Ended
	Jun. 30, 2021 USD ($) item	Jun. 30, 2020 USD ($)	Mar. 31, 2021 USD ($)
Leases
Number of option period for time charter | item	0
Operating lease liabilities - Time Charter in VLGCs	$ 14,800,000
Operating Lease, Expense	$ 151,676	$ 118,259
Weighted average discount rate (as a percent)	3.88%
Weighted average remaining lease term	18 months 27 days
Operating lease right-of-use assets - Office Leases	$ 528,672
Operating lease right-of-use assets - Time Charter in VLGCs	14,789,225
Operating lease liabilities current - Office Leases	408,353
Operating lease liabilities current - Time Charter in VLGCs	9,238,210
Operating lease liabilities non-current - Office Leases	117,284
Operating lease liabilities non-current - Time Charter in VLGCs	5,551,015
Operating lease right-of-use assets	15,317,897		$ 17,672,227
Operating lease liability	15,314,862
Charter hire expense
Leases
Operating lease income	$ 4,100,000	$ 6,900,000
Minimum
Leases
Weighted average discount rate (as a percent)	3.82%
Maximum
Leases
Weighted average discount rate (as a percent)	5.53%