Derivative Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other Assets
Gross position(1)	$ 7,808	$ 15,314
Impact of master netting agreement	(7,808)	(9,278)
Derivative values with impact of master netting agreements (as carried on balance sheet)	0	6,036
Cash collateral (held) pledged	0	(1,070)
Net position	0	4,966
Other Liabilities
Cash collateral (held) pledged	49,100	54,800
Other Liabilities
Other Liabilities
Gross position(1)	(25,937)	(30,497)
Impact of master netting agreement	7,808	9,278
Derivative values with impact of master netting agreements (as carried on balance sheet)	(18,129)	(21,219)
Cash collateral (held) pledged	48,134	54,845
Net position	$ 30,005	$ 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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