Derivative Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other Assets
Gross position	$ 2,090	$ 812
Impact of master netting agreement	(1,389)	(812)
Derivative values with impact of master netting agreements (as carried on balance sheet)	701	0
Cash collateral (held) pledged	(27,151)	0
Net position	27,852	0
Other Liabilities
Cash collateral (held) pledged	27,200	21,600
Other Liabilities
Other Liabilities
Gross position	(2,032)	(2,584)
Impact of master netting agreement	1,389	812
Derivative values with impact of master netting agreements (as carried on balance sheet)	(643)	(1,772)
Cash collateral (held) pledged	0	21,586
Net position	$ (643)	$ 19,814

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