Derivative, Brokerage Fee, Percent

No definition available.

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- Definition

Derivative, Daily Payments Received

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Derivative, Deduction from Daily Payments Made

+ References

No definition available.

+ Details

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- Definition

Derivative, Number of Vessel-Equivalents in Swap Agreement

+ References

No definition available.

+ Details

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- Definition

Derivative, Term of Contract Extension, Counterparty Option

+ References

No definition available.

+ Details

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ 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)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Number 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))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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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- Definition

The percentage of expected requirements covered by the aggregate notional amount of derivative contracts expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract as a percentage of expected need.

+ References

No definition available.

+ Details

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

- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

Derivative Instruments - Additional Information (Details)	May 01, 2017	Jun. 01, 2016 USD ($) vessel	Sep. 30, 2018 shares	Dec. 31, 2017 shares	Jan. 31, 2014 shares
Time-charter swap agreement
Derivative [Line Items]
Aframax equivalent vessel percent		55.00%
Derivative, number of vessel-equivalents in swap agreement \| vessel		2
Agreement daily receivable \| $		$ 27,776
Derivative, brokerage fee, percent		1.25%
Derivative, deduction from daily payments made \| $		$ 500
Derivative, term of contract (in months)		11 months
Derivative, term of contract extension, counterparty option (in months)	2 months	2 months
Tanker Investments Ltd. \| Maximum
Derivative [Line Items]
Number of shares available through exercise of stock purchase warrant (in shares)					750,000
Tanker Investments Ltd. \| Stock purchase warrant
Derivative [Line Items]
Number of stock purchase warrants (in warrants)				1
Tanker Investments Ltd. \| Stock purchase warrant \| Maximum
Derivative [Line Items]
Number of shares available through exercise of stock purchase warrant (in shares)			750,000