Represents the number of Company vessels that are operating under pooling agreement.

No definition available.

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- Definition

Represents the number of directors that can be appointed to the board of directors pursuant to the agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the Number of third party vessels that are operating under pooling agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the number of vessels that are operating under pooling agreement.

+ References

No definition available.

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- Definition

Represents the ownership interest held by related party.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of cost reimbursed by the Company for employee related travel and office-related costs.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of fixed reimbursement of expense from Helios.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the amount of working capital contributed to a related party.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=lpg_DorianHellasSAMember
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Transactions with Related Parties (Details)		3 Months Ended		9 Months Ended
Transactions with Related Parties (Details)	Apr. 01, 2015 item	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($)	Mar. 31, 2017 USD ($)	Jul. 26, 2013
Transactions with Related Parties
Related party income for chartering and operational services		$ 633,883	$ 670,836	$ 1,905,836	$ 1,776,659
Due from related parties		31,836,058		31,836,058		$ 42,457,000
Eagle Ocean Transport \| Maximum
Transactions with Related Parties
Reimbursed travel and office-related costs		100,000	100,000	100,000	300,000
Manager
Transactions with Related Parties
Due from related parties		900,000		900,000		800,000
Mr. John Hadjipateras \| Eagle Ocean Transport
Transactions with Related Parties
Ownership interest (as a percent)							100.00%
Vice President of Chartering, Insurance and Legal, Nigel Grey-Turner \| HSSL
Transactions with Related Parties
Ownership interest (as a percent)							100.00%
Helios LPG Pool LLC
Transactions with Related Parties
Due from related parties		50,700,000		$ 50,700,000		61,400,000
Interest transferred to Dorian LPG Ltd. (as a percent)	50.00%
Number of members \| item	2
Number of vessels that are operating under pooling agreement \| item				25
Number of Company vessels that are operating under pooling agreement \| item				18
Working capital contributed		19,800,000		$ 19,800,000		$ 19,800,000
Helios LPG Pool LLC \| Phoenix
Transactions with Related Parties
Number of third party vessels that are operating under pooling agreement \| item				4
Helios LPG Pool LLC \| Oriental Energy
Transactions with Related Parties
Number of third party vessels that are operating under pooling agreement \| item				3
Other income-related party \| Helios LPG Pool LLC
Transactions with Related Parties
Related party income for chartering and operational services		500,000	600,000	$ 1,600,000	1,500,000
Other income
Transactions with Related Parties
Fixed reimbursement of expense from Helios		100,000	200,000	100,000	700,000
Other income \| Manager
Transactions with Related Parties
Related party income for chartering and operational services		$ 100,000	$ 100,000	$ 300,000	$ 300,000