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

No definition available.

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Balance Type:	na
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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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Namespace Prefix:	lpg_
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Represents the ownership interest held by related party.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of fixed reimbursement of expense from Helios.

+ References

No definition available.

+ Details

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Namespace Prefix:	lpg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	lpg_
Data Type:	xbrli:monetaryItemType
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(11))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=lpg_DorianHellasSAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_BoardOfDirectorsChairmanMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_VicePresidentMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=lpg_HighburyShippingServicesLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=lpg_HeliosLPGPoolLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=lpg_PhoenixMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=lpg_OrientalEnergyCompanyMember
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Data Type:	na
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- Details

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Transactions with Related Parties (Details)	3 Months Ended		6 Months Ended
Transactions with Related Parties (Details)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) item	Sep. 30, 2016 USD ($)	Mar. 31, 2017 USD ($)	Jul. 26, 2013
Transactions with Related Parties
Fees for chartering and operational services	$ 638,070	$ 552,922	$ 1,271,953	$ 1,105,823
Due from related parties	26,802,209		26,802,209		$ 42,457,000
Eagle Ocean Transport \| Maximum
Transactions with Related Parties
Reimbursed travel and office-related costs	100,000	100,000	100,000	200,000
Manager
Transactions with Related Parties
Due from related parties	800,000		800,000		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	45,000,000		$ 45,000,000		61,400,000
Number of vessels that are operating under pooling agreement \| item			28
Number of Company vessels that are operating under pooling agreement \| item			17
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			5
Helios LPG Pool LLC \| Oriental Energy
Transactions with Related Parties
Number of third party vessels that are operating under pooling agreement \| item			6
Other income-related party \| Helios LPG Pool LLC
Transactions with Related Parties
Fees for chartering and operational services	500,000	500,000	$ 1,100,000	900,000
Other income
Transactions with Related Parties
Fixed reimbursement of expense from Helios		300,000		500,000
Other income \| Maximum
Transactions with Related Parties
Fixed reimbursement of expense from Helios	100,000		100,000
Other income \| Manager
Transactions with Related Parties
Fees for chartering and operational services	$ 100,000	$ 100,000	$ 200,000	$ 200,000