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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

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- Definition

Fair value as of the balance sheet date of all foreign currency derivatives designated as cash flow hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(b),(c)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624163-113959

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Risk Management and Use of Derivative Financial Instruments - Foreign Currency Derivatives Details (Details) € in Thousands, £ in Thousands, kr in Thousands, $ in Thousands	Sep. 30, 2020 USD ($) numberOfDerivativeInstrument	Sep. 30, 2020 EUR (€) numberOfDerivativeInstrument	Sep. 30, 2020 GBP (£) numberOfDerivativeInstrument	Sep. 30, 2020 NOK (kr) numberOfDerivativeInstrument
Derivative Disclosure
Fair value, foreign currency derivatives	$ 7,602
Derivatives Designated as Hedging Instruments \| Designated as Cash Flow Hedging Instruments \| Foreign currency collars \| EUR
Derivative Disclosure
Number of Instruments \| numberOfDerivativeInstrument	88	88	88	88
Notional Amount \| €		€ 308,000
Fair value, foreign currency derivatives	$ 5,975
Derivatives Designated as Hedging Instruments \| Designated as Cash Flow Hedging Instruments \| Foreign currency collars \| GBP
Derivative Disclosure
Number of Instruments \| numberOfDerivativeInstrument	65	65	65	65
Notional Amount \| £			£ 44,000
Fair value, foreign currency derivatives	$ 1,620
Derivatives Designated as Hedging Instruments \| Designated as Cash Flow Hedging Instruments \| Foreign currency collars \| NOK
Derivative Disclosure
Number of Instruments \| numberOfDerivativeInstrument	1	1	1	1
Notional Amount \| kr				kr 700
Fair value, foreign currency derivatives	$ 7