Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the final settlement amount of derivative instrument payable during the period.

+ References

No definition available.

+ Details

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

- Definition

Represents the semi-annual amount of derivative instrument payable during the period.

+ References

No definition available.

+ Details

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

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeFixedInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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

- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5579245-113959

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
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Derivative Instruments (Predecessor) (Details) (USD $)	Mar. 31, 2015 item	Mar. 31, 2013 item	Apr. 03, 2007	Feb. 07, 2012	Jan. 08, 2009
Interest rate swaps
Derivative Instruments
Number of interest rate swaps	5
Notional amount	$ 117,924,000
Predecessor \| Interest rate swaps
Derivative Instruments
Number of interest rate swaps		5
Notional amount		136,718,000
Predecessor \| Interest rate swaps \| Cetus
Derivative Instruments
Notional amount			51,140,000
Semi-annual reduction of notional amount			1,278,500
Final settlement amount			20,456,000
Predecessor \| Interest rate swaps \| Lyra
Derivative Instruments
Notional amount				64,146,313
Semi-annual reduction of notional amount				1,700,000
Final settlement amount				28,900,000
Predecessor \| 5.395% interest rate swap due on Nov 2018 \| Cetus
Derivative Instruments
Fixed interest rate (as a percent)			5.395%
Predecessor \| 4.936% interest rate swap due on Nov 2018 \| Cetus
Derivative Instruments
Fixed interest rate (as a percent)			4.936%
Predecessor \| 4.772% interest rate swap due on March 2019 \| Lyra
Derivative Instruments
Fixed interest rate (as a percent)				4.772%
Predecessor \| 2.960% interest rate swap due on March 2019 \| Lyra
Derivative Instruments
Fixed interest rate (as a percent)				2.96%
Predecessor \| 4.350% interest rate swap due on July 2020 \| Cepheus
Derivative Instruments
Notional amount					68,800,000
Fixed interest rate (as a percent)					4.35%
Semi-annual reduction of notional amount					1,720,000
Final settlement amount					$ 29,240,000