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

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ 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.

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- Definition

The net gain (loss) during the reporting period due to ineffectiveness in foreign currency cash flow hedges. Recognized in earnings.

+ 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 (d)(1)

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

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Derivative Instruments And Hedging Activities (Narrative) (Details) NOK in Millions, $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2013 USD ($)	Feb. 28, 2013 USD ($)	Feb. 28, 2013 NOK	Jan. 31, 2013 USD ($)	Jan. 31, 2013 NOK
Derivative [Line Items]
Gain (loss) on foreign currency cash flow hedge ineffectiveness	$ 0.2	$ (3.2)
Future losses to be re-classified to earnings		10.5
Grand Canyon [Member]
Derivative [Line Items]
Derivative, notional amount						$ 104.6	NOK 591.3
Grand Canyon II [Member]
Derivative [Line Items]
Derivative, notional amount				$ 100.4	NOK 594.7
Grand Canyon III [Member]
Derivative [Line Items]
Derivative, notional amount				$ 98.8	NOK 595.0
Term Loan Maturing June 2018 [Member] \| Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative, notional amount			$ 148.1
Nordea Term Loan [Member] \| Interest Rate Swaps [Member]
Derivative [Line Items]
Derivative, notional amount	$ 187.5	$ 187.5