Represents the number of fuel-efficient Eco-design Very Large Gas Carrier vessels in current fleet having a capacity of 84,000 cubic meters.

No definition available.

Name:	lpg_NumberOfFuelEfficientVeryLargeGasCarrierVesselsEightyFourThousandCapacity
Namespace Prefix:	lpg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the number of pressurized vessels in current fleet having a capacity of 5,000 cubic meters.

No definition available.

Name:	lpg_NumberOfPressurizedGasCarrierVesselsFiveThousandCapacity
Namespace Prefix:	lpg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the number of Very Large Gas Carrier vessels in current fleet having a capacity of 82,000 cubic meters.

No definition available.

Name:	lpg_NumberOfVeryLargeGasCarrierVesselsEightyTwoThousandCapacity
Namespace Prefix:	lpg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the number of commitments under shipbuilding contracts and supervision agreements for VLGC newbuildings.

No definition available.

Name:	lpg_NumberOfVeryLargeGasCarrierVesselsUnderCommitment
Namespace Prefix:	lpg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the number of Very Large Gas Carrier vessels in the current fleet with minimum capacity of 80,000 cubic meters.

No definition available.

Name:	lpg_NumberOfVeryLargeGasCarrierVesselsWithMinimumEightyThousandCapacity
Namespace Prefix:	lpg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the operational time period of the vessels entered.

No definition available.

Name:	lpg_OperatingPeriodOfVesselsEntered
Namespace Prefix:	lpg_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the ownership interest held by related party.

No definition available.

Name:	lpg_OwnershipPercentageHeldByRelatedParty
Namespace Prefix:	lpg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Basis of Presentation and General Information (Details) - item			3 Months Ended
	Oct. 22, 2015	Apr. 01, 2015	Sep. 30, 2015
Number of commitments under shipbuilding contracts and supervision agreements for VLGC newbuildings			8
Subsequent events
Number of VLGCs with minimum 80,000 cbm	17
Number of fuel-efficient ECO-design VLGCs having 84,000 cbm	13
Number of VLGCs having 82,000 cbm	3
Number of PGCs having 5,000 cbm	1
Number of commitments under shipbuilding contracts and supervision agreements for VLGC newbuildings	6
Helios LPG Pool LLC
Ownership interest (as a percent)			50.00%
Maximum
Operating period of the vessels entered		2 years