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

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- Definition

Amount of contractual obligation due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount of contractual obligation due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Average contractual rate at which a foreign currency can be purchased or sold.

+ References

No definition available.

+ 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.

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- Definition

Fair value as of the balance sheet date of all foreign currency derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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Derivative Instruments - Foreign Currency Forward Contracts (Details) $ in Thousands	Dec. 31, 2017 USD ($)	Dec. 31, 2017 NOK (kr)	Dec. 31, 2017 EUR (€)
Foreign currency forward contracts
Derivative [Line Items]
Fair Value / Carrying Amount of Asset/(Liability) Non-hedge	$ (357)
Expected Maturity - 2018	51,661
Expected Maturity - 2019	$ 6,849
Norwegian Kroner
Derivative [Line Items]
Contract Amount in Foreign Currency \| kr		kr 365,000,000
Average Forward Rate	8.07	8.07	8.07
Norwegian Kroner \| Foreign currency forward contracts
Derivative [Line Items]
Fair Value / Carrying Amount of Asset/(Liability) Non-hedge	$ (455)
Expected Maturity - 2018	38,390
Expected Maturity - 2019	$ 6,849
Euro
Derivative [Line Items]
Contract Amount in Foreign Currency \| €			€ 11,000,000
Average Forward Rate	0.83	0.83	0.83
Euro \| Foreign currency forward contracts
Derivative [Line Items]
Fair Value / Carrying Amount of Asset/(Liability) Non-hedge	$ 98
Expected Maturity - 2018	13,271
Expected Maturity - 2019	$ 0