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)
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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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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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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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The amount of net gain (loss) reclassified into earnings when foreign currency cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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Derivative Instruments And Hedging Activities - Narrative (Details) $ in Thousands, NOK in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2015 NOK	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]
Unrealized loss on hedges, net	$ 27,891	$ 18,021	$ 27,891
Unrealized losses related to foreign exchange contracts	18,000
Loss in Accumulated OCI to be reclassified within twelve months		9,600
Grand Canyon [Member]
Derivative [Line Items]
Notional amount										$ 104,600	NOK 591.3
Grand Canyon II [Member]
Derivative [Line Items]
Notional amount					NOK 434.1			$ 100,400	NOK 594.7
Grand Canyon III [Member]
Derivative [Line Items]
Notional amount					NOK 185.2			$ 98,800	NOK 595.0
Interest Rate Swaps [Member]
Derivative [Line Items]
Notional amount							$ 148,100
Interest Rate Swaps [Member] \| Nordea Q5000 Loan Maturing April 2020 [Member]
Derivative [Line Items]
Notional amount						$ 187,500
Cash Flow Hedging [Member] \| Foreign Exchange Contracts [Member]
Derivative [Line Items]
Unrealized loss on hedges, net	$ 19,800		19,800
Other Income (Expense), Net [Member] \| Grand Canyon [Member]
Derivative [Line Items]
Realized loss on hedge ineffectiveness		(100)
Unrealized loss on hedge ineffectiveness		$ 0	1,500
Other Income (Expense), Net [Member] \| Grand Canyon II [Member]
Derivative [Line Items]
Realized loss on hedge ineffectiveness				$ 500
Unrealized loss on hedge ineffectiveness				$ 1,200
Other Income (Expense), Net [Member] \| Grand Canyon II and Grand Canyon III [Member]
Derivative [Line Items]
Realized loss on hedge ineffectiveness			$ 3,600