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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- Definition

Derivative, Deduction from Daily Payments Made

+ References

No definition available.

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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 Consecutive Trading Period

+ References

No definition available.

+ Details

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- Definition

Number Of Tranches

+ References

No definition available.

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- Definition

Number of tranches vested

+ References

No definition available.

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- 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

+ Details

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Balance Type:	na
Period Type:	instant

- 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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Period Type:	instant

- Definition

The cap rate on a price risk derivative such as a cap or collar. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract.

+ References

No definition available.

+ Details

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- Definition

Description of the reasons for holding or issuing the derivative instrument. Includes discussion of the objective for holding the instrument, the context needed to understand that objective, and the strategy for achieving the objective.

+ 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=84234895&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
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579240-113959

+ Details

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

+ Details

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- 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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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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- 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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Derivative Instruments - Additional Information (Details)			9 Months Ended
	May 01, 2017	Jun. 01, 2016 USD ($) vessel	Sep. 30, 2017 USD ($) tranche $ / shares NOK / Derivative shares	Sep. 30, 2017 NOK / shares	Dec. 31, 2016 USD ($)
Derivative [Line Items]
Stock purchase warrant			$ 3,022,000		$ 4,538,000
Interest rate swap agreements
Derivative [Line Items]
Derivative, description of objective			The Company enters into interest rate swap agreements which exchange a receipt of floating interest for a payment of fixed interest to reduce the Company’s exposure to interest rate variability on its outstanding floating-rate debt.
Stock purchase warrant			$ 3,022,000		4,251,000
Stock purchase warrant
Derivative [Line Items]
Stock purchase warrant					$ 287,000
Stock purchase warrant \| Tanker Investments Ltd.
Derivative [Line Items]
Fixed price of stock purchase warrants, per share (usd per share) \| (per share)			$ 10	NOK 61.67
Number of tranches \| tranche			4
Consecutive trading days			10 days
Number of tranches vested \| tranche			2
Stock purchase warrant			$ 0
Stock purchase warrant \| Tanker Investments Ltd. \| Maximum
Derivative [Line Items]
Number of shares available through exercise of stock purchase warrant (shares) \| shares			750,000
Stock purchase warrant \| Tanker Investments Ltd. \| Minimum \| Tranche One
Derivative [Line Items]
Fair market value of the shares \| NOK / Derivative			77.08
Stock purchase warrant \| Tanker Investments Ltd. \| Minimum \| Tranche Two
Derivative [Line Items]
Fair market value of the shares \| NOK / Derivative			92.5
Stock purchase warrant \| Tanker Investments Ltd. \| Minimum \| Tranche Three
Derivative [Line Items]
Fair market value of the shares \| NOK / Derivative			107.91
Stock purchase warrant \| Tanker Investments Ltd. \| Minimum \| Tranche Four
Derivative [Line Items]
Fair market value of the shares \| NOK / Derivative			123.33
Time-charter swap agreement
Derivative [Line Items]
Aframax equivalent vessel percent		55.00%	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
Forward freight agreements
Derivative [Line Items]
Derivative, description of objective			The Company uses forward freight agreements (or FFAs) in non-hedge-related transactions to increase or decrease its exposure to spot market rates, within defined limits.