Financial Instruments and Fair Value Disclosures (Details 2) (USD $)	Mar. 31, 2015
Interest rate swaps
Derivative Instruments
Notional amount	$ 117,924,000
Interest rate swaps \| CMNL LPG Transport LLC
Derivative Instruments
Semi-annual reduction of notional amount	1,278,500
Final settlement amount	21,734,500
Interest rate swaps \| CJNP LPG Transport LLC
Derivative Instruments
Semi-annual reduction of notional amount	1,700,000
Final settlement amount	28,900,000
5.395% interest rate swap due on Nov 2018 \| CMNL LPG Transport LLC
Derivative Instruments
Fixed interest rate (as a percent)	5.395%
Notional amount	20,456,000
4.936% interest rate swap due on Nov 2018 \| CMNL LPG Transport LLC
Derivative Instruments
Fixed interest rate (as a percent)	4.936%
Notional amount	10,228,000
4.772% interest rate swap due on March 2019 \| CJNP LPG Transport LLC
Derivative Instruments
Fixed interest rate (as a percent)	4.772%
Notional amount	30,523,500
2.960% interest rate swap due on March 2019 \| CJNP LPG Transport LLC
Derivative Instruments
Fixed interest rate (as a percent)	2.96%
Notional amount	10,276,500
4.350% interest rate swap due on July 2020 \| CNML LPG Transport LLC
Derivative Instruments
Fixed interest rate (as a percent)	4.35%
Notional amount	46,440,000
Interest rate swap due on July 2020 \| Royal Bank of Scotland plc (RBS)
Derivative Instruments
Semi-annual reduction of notional amount	1,720,000
Final settlement amount	$ 27,520,000

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

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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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