Investment Securities - Realized Gains and Losses From Sale of Securities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Realized Investment Gains (Losses) [Abstract]
Gross gains	$ 116	$ 51	$ 934	$ 365
Gross losses	$ (21)	$ 0	$ (21)	$ (42)