Derivative Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Other Liabilities
Cash collateral pledged	$ 65,000	$ 27,000
Other Assets
Other Assets
Gross position	772	2,090
Impact of master netting agreement	(359)	(1,389)
Derivative values with impact of master netting agreements (as carried on balance sheet)	413	701
Cash collateral pledged	65,183	27,151
Net position	65,596	27,852
Other Liabilities
Other Liabilities
Gross position	(359)	(2,032)
Impact of master netting agreement	359	1,389
Derivative values with impact of master netting agreements (as carried on balance sheet)	0	(643)
Cash collateral pledged	0	0
Net position	$ 0	$ (643)

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