Derivative Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Other Liabilities
Cash collateral pledged	$ 74,000	$ 27,000
Other Assets
Other Assets
Gross position	275	2,090
Impact of master netting agreement	(142)	(1,389)
Derivative values with impact of master netting agreements (as carried on balance sheet)	133	701
Cash collateral pledged	73,527	27,151
Net position	73,660	27,852
Other Liabilities
Other Liabilities
Gross position	(1,238)	(2,032)
Impact of master netting agreement	142	1,389
Derivative values with impact of master netting agreements (as carried on balance sheet)	(1,096)	(643)
Cash collateral pledged	0	0
Net position	$ (1,096)	$ (643)

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