Accumulated Other Comprehensive Loss (Components of Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Net unrealized gains (losses), before tax	$ (13,096)	$ (5,943)
Net unrealized tax (expense) benefit	3,503	1,608
Other comprehensive loss, net of tax	(9,593)	(4,335)
Accumulated Other Comprehensive Loss [Member]
Unrealized net gains (losses), net of tax	(9,877)		$ 409
Recognized gains (losses), net of tax	(284)		(1,140)
Other comprehensive loss, net of tax	(9,593)	(4,335)
Investment securities- with OTTI [Member]
Unrealized net gains (losses), before tax	141	363
Recognized gains (losses), before tax	50	50
Net unrealized gains (losses), before tax	91	313
Unrealized tax (expense) benefit	(38)	(97)
Net unrealized tax (expense) benefit	(25)	(84)
Unrealized net gains (losses), net of tax	103	266	2,475
Recognized gains (losses), net of tax	37		147
Other comprehensive loss, net of tax	66	229
Investment securities- with OTTI [Member] | Accretable Yield in Income [Member]
Recognized gains (losses), before tax	50	50
Recognized tax (expense) benefit	(13)	(13)
Recognized gains (losses), net of tax	37	37
Investment securities- all other [Member]
Unrealized net gains (losses), before tax	(10,844)	(7,105)
Recognized gains (losses), before tax	3
Net unrealized gains (losses), before tax	(2,519)	(7,105)
Unrealized tax (expense) benefit	2,901	1,903
Net unrealized tax (expense) benefit	674	1,903
Unrealized net gains (losses), net of tax	(7,943)	(5,202)
Other comprehensive loss, net of tax	(1,845)	(5,202)
Investment securities- all other [Member] | Recognition of Gains (Losses) In Income [Member]
Recognized gains (losses), before tax	3
Recognized tax (expense) benefit	(1)
Recognized gains (losses), net of tax	2
Investment Securities HTM [Member]
Recognized gains (losses), before tax	(94)	(61)
Net unrealized gains (losses), before tax	(8,234)	61
Net unrealized tax (expense) benefit	2,203	(16)
Unrealized net gains (losses), net of tax	(6,100)
Recognized gains (losses), net of tax	(69)		(181)
Other comprehensive loss, net of tax	(6,031)	45
Investment Securities HTM [Member] | Amortization of Recognized Income [Member]
Recognized gains (losses), before tax	(94)	(61)
Recognized tax (expense) benefit	25	16
Recognized gains (losses), net of tax	(69)	(45)
Investment Securities Transferred From AFS to HTM [Member]
Unrealized net gains (losses), before tax	8,328
Unrealized tax (expense) benefit	(2,228)
Unrealized net gains (losses), net of tax	6,100
Investment Securities Transferred to HTM [Member]
Unrealized net gains (losses), before tax	(8,328)
Unrealized tax (expense) benefit	2,228
Unrealized net gains (losses), net of tax	(6,100)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Unrealized net gains (losses), before tax	839
Net unrealized gains (losses), before tax		532
Unrealized tax (expense) benefit	(225)
Net unrealized tax (expense) benefit		(127)
Unrealized net gains (losses), net of tax	614		635
Other comprehensive loss, net of tax	614	405
Pension Plan [Member]
Unrealized net gains (losses), before tax	(3,620)	(190)
Recognized gains (losses), before tax	(279)	(372)
Net unrealized gains (losses), before tax	(3,341)	182
Pension Plan [Member] | Pension [Member]
Unrealized net gains (losses), before tax	(3,620)	(190)
Net unrealized gains (losses), before tax	(3,341)	182
Unrealized tax (expense) benefit	969	51
Net unrealized tax (expense) benefit	894	(49)
Unrealized net gains (losses), net of tax	(2,651)	(139)	3,431
Recognized gains (losses), net of tax	(204)		(1,091)
Other comprehensive loss, net of tax	(2,447)	133
Pension Plan [Member] | SERP [Member]
Recognized gains (losses), before tax		74
Net unrealized gains (losses), before tax	68
Net unrealized tax (expense) benefit	(18)	(19)
Unrealized net gains (losses), net of tax			(521)
Recognized gains (losses), net of tax	(50)		$ (128)
Other comprehensive loss, net of tax	50	55
Pension Plan [Member] | Amortization of Unrecognized Loss [Member] | Pension [Member]
Recognized gains (losses), before tax	(279)	(372)
Recognized tax (expense) benefit	75	100
Recognized gains (losses), net of tax	(204)	(272)
Pension Plan [Member] | Amortization of Unrecognized Loss [Member] | SERP [Member]
Recognized gains (losses), before tax	(68)	(75)
Recognized tax (expense) benefit	18	19
Recognized gains (losses), net of tax	$ (50)	(56)
Pension Plan [Member] | Amortization of Prior Service Costs [Member] | SERP [Member]
Recognized gains (losses), before tax		1
Recognized gains (losses), net of tax		$ 1