Derivative Instruments And Hedging Activities - Narrative (Details) NOK in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 NOK	Jun. 30, 2015 USD ($)	Sep. 30, 2013 USD ($)	Feb. 28, 2013 NOK	Feb. 28, 2013 USD ($)	Jan. 31, 2013 NOK	Jan. 31, 2013 USD ($)
Derivative [Line Items]
Losses in Accumulated OCI to be re-classified within twelve months	$ 8.8
Interest Rate Swaps [Member] | Term Loan Maturing June 2018 [Member]
Derivative [Line Items]
Notional amount					$ 148.1
Interest Rate Swaps [Member] | Nordea Q5000 Loan Maturing April 2020 [Member]
Derivative [Line Items]
Notional amount				$ 187.5
Grand Canyon [Member]
Derivative [Line Items]
Notional amount								NOK 591.3	$ 104.6
Grand Canyon II [Member]
Derivative [Line Items]
Notional amount			NOK 434.1			NOK 594.7	$ 100.4
Grand Canyon I I I [Member]
Derivative [Line Items]
Notional amount			NOK 185.2			NOK 595.0	$ 98.8
Foreign Exchange Contracts For Grand Canyon And Grand Canyon III [Member] | Other Income (Expense), Net [Member]
Derivative [Line Items]
Unrealized loss on hedge ineffectiveness	$ 0.4
Foreign Exchange Contracts For Grand Canyon II [Member] | Other Income (Expense), Net [Member]
Derivative [Line Items]
Realized losses on hedge ineffectiveness		$ 0.2
Foreign Exchange Contracts For Grand Canyon III [Member] | Other Income (Expense), Net [Member]
Derivative [Line Items]
Unrealized loss on hedge ineffectiveness		$ 3.4