Derivative Financial Instruments (Details 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Derivative Assets
Counterparty set-off	$ (31,548)	$ (13,258)
Total derivative asset net fair value	160,217us-gaap_DerivativeAssets	12,138us-gaap_DerivativeAssets
Short term derivative asset
Derivative Assets
Assets	191,765	15,859
Liabilities		2,826
Asset fair value	191,765	18,685
Long term derivative asset
Derivative Assets
Liabilities		223
Asset fair value		6,711
Other assets
Derivative Assets
Assets		$ 6,488

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. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References+ Details

Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References+ Details