Other Derivatives - Cash flow hedges (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Gross Amount of Recognized Liabilities	$ 6,459		$ 611
Amount of Gain or (Loss) recognized in OCI	(1,989)	$ (1,545)
Designated Cash Flow Hedge \| Interest Rate Product
Amount of Gain or (Loss) recognized in OCI	(1,521)	(1,034)
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income	28	(367)
Designated Cash Flow Hedge \| Interest Rate Product \| Interest Expense
Amount of Gain or (Loss) recognized in OCI	(1,521)	(1,034)
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income	28	462
Designated Cash Flow Hedge \| Interest Rate Product \| Gain on sale of investment securities
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income		(829)
Designated Cash Flow Hedge \| Interest Rate Swap
Notional Amount	$ 100,000	100,000
Designated Cash Flow Hedge \| Interest Rate Swap \| Non-interest income
Gross Amount of Recognized Liabilities		$ 829

Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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