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

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

+ References

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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

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- Definition

Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of 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 50

-Paragraph 4C

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

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Financial Instruments Foreign currency forward contracts (Details) - Not Designated as Hedging Instrument [Member]	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 GBP (£)	Jun. 30, 2015 SEK	Jun. 30, 2015 AUD	Jun. 30, 2015 EUR (€)	Jun. 30, 2015 INR (₨)	Jun. 30, 2015 NOK	Jun. 30, 2015 USD ($)
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments \| $	$ (911,000)	$ (27,000)	$ 1,561,000	$ 312,000
Cross Currency Interest Rate Contract [Member]
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments \| $	$ (84,000)	$ 0	$ (84,000)	$ 0
Derivative, Notional Amount								€ 12,000,000
Derivative, Forward Exchange Rate					0	0	0	0	0	0	0
EUR/NOK [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount								€ 3,369,666
EUR/NOK [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount \| NOK										NOK 29,400,000
EUR/USD 1 [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount								11,750,987
EUR/USD 1 [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount \| $											$ 13,100,000
USD/GPB [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount \| £					£ 826,656
USD/GPB [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount \| $											1,300,000
EUR/GBP [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount \| £					£ 887,750
EUR/GBP [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount								1,250,000
EUR/AUD [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount								1,381,884
EUR/AUD [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount \| AUD							AUD 2,000,000
SEK/EUR [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount \| SEK						SEK 16,642,260
SEK/EUR [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount								1,800,000
USD/INR [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount \| $											$ 7,050,000
USD/INR [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount \| ₨									₨ 450,965,235
EUR/INR [Member] \| Forward Contracts [Member] \| Short [Member]
Derivative [Line Items]
Derivative, Notional Amount								€ 2,500,000
EUR/INR [Member] \| Forward Contracts [Member] \| Long [Member]
Derivative [Line Items]
Derivative, Notional Amount \| ₨									₨ 178,245,750