Derivative Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Other Assets
Gross position	$ 65,116	$ 15,314
Impact of master netting agreement	(16,173)	(9,278)
Derivative values with impact of master netting agreements (as carried on balance sheet)	48,943	6,036
Cash collateral (held) pledged	(16,659)	(1,070)
Net position	32,284	4,966
Other Liabilities
Gross position	(60,892)	(30,497)
Impact of master netting agreement	16,173	9,278
Derivative values with impact of master netting agreements (as carried on balance sheet)	(44,719)	(21,219)
Cash collateral (held) pledged	53,555	54,845
Net position	$ 8,836	$ 33,626

Fair value of liability associated with 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.

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