Represents the brokerage commission fee on exercised purchase option excluding deposit.

No definition available.

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- Definition

Represents the percent of outstanding common shares that the rights become exercisable following a public announcement of an acquisition, or right to acquire the shares.

+ References

No definition available.

+ Details

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- Definition

Represents the number of rights for each outstanding share of common stock distributed as dividends.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the amount of restricted cash released.

+ References

No definition available.

+ Details

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

- Definition

Represents the amount of balloon payment.

+ 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 deposit value held by the buyer from sale of property, plant and equipment.

+ References

No definition available.

+ Details

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

- Definition

The estimated amount of financing costs.

+ References

No definition available.

+ Details

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

- Definition

The monthly brokerage commission percentage.

+ References

No definition available.

+ Details

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

- Definition

Represents the number of year until the purchase option becomes exercisable.

+ References

No definition available.

+ Details

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

- Definition

Represents the value of property plant and equipment transferred.

+ References

No definition available.

+ Details

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

- Definition

Represents the term of the bareboat charter agreement.

+ References

No definition available.

+ Details

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

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: 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.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

- Definition

Amount of the required periodic payments applied to principal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- References

No definition available.

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions	Jan. 31, 2018	May 31, 2017	Dec. 16, 2016
Expiration of Shareholder Rights Plan
Dividend issued for each share of common stock (in shares)			1
Exercise price of rights (in dollars per share)			$ 60
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right			1
Subsequent events
Subsequent Events
Proceeds from sale of vessel	$ 56.0
2015 Debt Facility
Subsequent Events
The amount of restricted cash released		$ 26.8
2015 Debt Facility \| Subsequent events
Subsequent Events
Repayment of debt	35.1
The amount of restricted cash released	$ 1.6
Concorde Japanese Financing \| Subsequent events
Subsequent Events
Stated rate (as a percent)	4.90%
Estimated financing cost to be incurred	$ 0.1
Monthly brokerage commission (as a percent)	1.25%
Brokerage commission fee on exercised purchase option excluding buyer deposit (as a percent)	1.00%
Periodic principal payment amount	$ 0.3
Principal payment frequency	monthly
Balloon payment amount	$ 14.0
Concorde LPG Transport LLC \| Subsequent events
Subsequent Events
Value of vessel transferred	$ 70.0
Term of Charter Agreement	13 years
Period until purchase option exercisable	3 years
Proceeds from sale of vessel	$ 56.0
Deposit retained by buyer	$ 14.0
Minimum
Expiration of Shareholder Rights Plan
Ownership to trigger rights exercisable (as a percent)			15.00%
Maximum
Expiration of Shareholder Rights Plan
Ownership to trigger rights exercisable (as a percent)			50.00%