Summary of Significant Accounting Policies (Schedule of Other, Net) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accounting Policies [Abstract]
Interest and dividend income	$ 1,251	$ 3,083	$ 5,331	$ 9,430
Net gains (losses) recognized on investment securities	2,516	(1,487)	(4,943)	5,601
Net periodic benefit cost other than the service costs	(452)	(576)	(1,361)	(1,692)
Credit loss expense	(8,576)	0	(9,008)	0
Other income	165	1,203	1,865	1,105
Other, net	$ (5,096)	$ 2,223	$ (8,116)	$ 14,444