Derivative Financial Instruments (Assets) (Details) $ in Thousands	Dec. 31, 2014 USD ($)
Derivative Financial Instruments
Assets	$ 191,765
Counterparty set-off/Assets	(31,548)
Total derivative asset net fair value	$ 160,217

Fair value, after the effects of master netting arrangements, of a financial asset or other 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, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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