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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Transactions with Related Parties (Details)	3 Months Ended		9 Months Ended
Transactions with Related Parties (Details)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)	Apr. 01, 2014	Jul. 26, 2013
Transactions with Related Parties
Related party income for chartering and operational services	$ 614,633	$ 633,883	$ 1,843,782	$ 1,905,836
Due from related parties	56,826,894		56,826,894		$ 26,880,720
Due to related parties	11,162		11,162		345,515
Eagle Ocean Transport
Transactions with Related Parties
Reimbursed office-related costs				100,000
Eagle Ocean Transport \| Maximum
Transactions with Related Parties
Reimbursed office-related costs	100,000	100,000	100,000
Manager
Transactions with Related Parties
Due from related parties	1,100,000		1,100,000		900,000
Mr. John Hadjipateras \| Eagle Ocean Transport
Transactions with Related Parties
Ownership interest (as a percent)							100.00%
Helios LPG Pool LLC
Transactions with Related Parties
Due from related parties	76,600,000		$ 76,600,000		45,400,000
Due to related party					300,000
Interest transferred to Dorian LPG Ltd. (as a percent)						50.00%
Number of vessels that are operating under pooling agreement \| item			29
Number of Company vessels that are operating under pooling agreement \| item			19
Working capital contributed	20,900,000		$ 20,900,000		$ 19,800,000
Helios LPG Pool LLC \| Phoenix
Transactions with Related Parties
Number of third party vessels that are operating under pooling agreement \| item			5
Helios LPG Pool LLC \| Oriental Energy
Transactions with Related Parties
Number of third party vessels that are operating under pooling agreement \| item			5
Other income-related party \| Manager
Transactions with Related Parties
Related party income for chartering and operational services	100,000	100,000	$ 200,000	300,000
Other income-related party \| Helios LPG Pool LLC
Transactions with Related Parties
Related party income for chartering and operational services	600,000	500,000	1,700,000	1,600,000
Other income
Transactions with Related Parties
Fixed reimbursement of expense from Helios	$ 100,000	$ 100,000	$ 300,000	$ 100,000