Derivatives - Offsetting Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Offsetting Liabilities [Line Items]
Gross Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	$ (298,685)	$ (233,301)
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(298,685)	(233,301)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Financial Instruments	298,685	233,301
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Cash Collateral Posted	0	0
Net Amount	0	0
Interest rate swap contracts
Offsetting Liabilities [Line Items]
Gross Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(298,685)	(233,301)
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(298,685)	(233,301)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Financial Instruments	298,685	233,301
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Cash Collateral Posted	0	0
Net Amount	$ 0	$ 0

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226016-175313

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Fair value, after effects of master netting arrangements, deduction of liabilities not subject to a master netting arrangement and elected not to be offset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against the right to receive collateral.

+ References

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- Definition

Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset, deducted from derivative liabilities.

+ 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

No definition available.

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