Other Derivatives - Designated cash flow hedges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Designated Cash Flow Hedge
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income	$ (389)	$ 264	$ (755)	$ 1,868
Interest Expenses
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Total amounts of income and expense line items presented in the statement of financial performance in which the effects of fair value or cash flow hedges are recorded	389	264	755	1,039
Interest Expenses | Designated Cash Flow Hedge
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income	389	264	755	1,039
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income as a result that a forecasted transaction is no longer probable of occurring				0
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income - Included Component	389	264	755	1,039
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income - Excluded Component	$ 0	$ 0	$ 0	0
Gain on sale of investment securities
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Total amounts of income and expense line items presented in the statement of financial performance in which the effects of fair value or cash flow hedges are recorded				829
Gain on sale of investment securities | Designated Cash Flow Hedge
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income				0
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income as a result that a forecasted transaction is no longer probable of occurring				829
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income - Included Component				829
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income - Excluded Component				$ 0