Derivative Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Other Liabilities
Cash collateral pledged	$ 32,000	$ 27,000
Other Assets
Other Assets
Gross position	2,060	2,090
Impact of master netting agreement	(1,231)	(1,389)
Derivative values with impact of master netting agreements (as carried on balance sheet)	829	701
Cash collateral pledged	31,915	27,151
Net position	32,744	27,852
Other Liabilities
Other Liabilities
Gross position	(3,981)	(2,032)
Impact of master netting agreement	1,231	1,389
Derivative values with impact of master netting agreements (as carried on balance sheet)	(2,750)	(643)
Cash collateral pledged	0	0
Net position	$ (2,750)	$ (643)

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