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 maturing in the remainder of the fiscal year following the latest fiscal year ended.

+ 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.

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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 and Hedging Activities - Foreign Currency Forward Contracts (Details) - Foreign currency forward contracts $ in Thousands	Sep. 30, 2018 USD ($)	Sep. 30, 2018 NOK (kr)	Sep. 30, 2018 EUR (€)
Derivative [Line Items]
Fair Value / Carrying Amount of Asset (Liability) Non-hedge	$ (1,568)
Expected Maturity, 2018	20,218
Expected Maturity, 2019	38,022
Norwegian Kroner
Derivative [Line Items]
Contract Amount in Foreign Currency \| kr		kr 430,000,000
Fair Value / Carrying Amount of Asset (Liability) Non-hedge	$ (1,422)
Average Forward Rate	7.88	7.88	7.88
Expected Maturity, 2018	$ 16,565
Expected Maturity, 2019	38,022
Euro
Derivative [Line Items]
Contract Amount in Foreign Currency \| €			€ 3,000,000
Fair Value / Carrying Amount of Asset (Liability) Non-hedge	$ (146)
Average Forward Rate	0.82	0.82	0.82
Expected Maturity, 2018	$ 3,653