Other Derivatives - Cash flow hedges (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net unrealized gain (loss) on derivatives	$ (2,049)	$ (2,731)	$ 2,033
Cash Flow Hedge | Interest Rate Product
Net unrealized gain (loss) on derivatives	(1,510)	(1,812)
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income	(1,146)	1,994
Cash Flow Hedge | Interest Rate Product | Interest Expense
Net unrealized gain (loss) on derivatives	(1,510)	(1,812)
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income	(1,146)	1,165
Cash Flow Hedge | Interest Rate Product | Gain on sale of investment securities
Net unrealized gain (loss) on derivatives	0
Amount of gain or (loss) reclassified from accumulated other comprehensive income into income	$ 0	$ 829