Accumulated Other Comprehensive Income (Loss) - AOCI Components Pre Post & Tax Effect (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Other Comprehensive Income (Loss), Before Tax:
Net Unrealized Gains (Losses) Arising During the Period	$ 6,022		$ (31,586)		$ 17,426	$ 1,332
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	6,294		6,801		12,496	13,714
Net Unrealized Gains (Losses) on Investment Securities	12,316		(24,785)		29,922	15,046
Amortization of Net Actuarial Losses (Gains)	291		177		582	352
Amortization of Prior Service Credit	(61)		(62)		(122)	(123)
Defined Benefit Plans, Net	230		115		460	229
Other Comprehensive Income (Loss)	12,546		(24,670)		30,382	15,275
Other Comprehensive Income (Loss), Tax Effect:
Net Unrealized Gains (Losses) Arising During the Period	1,595		(8,371)		4,619	352
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	1,669		1,803		3,313	3,635
Net Unrealized Gains (Losses) on Investment Securities	3,264		(6,568)		7,932	3,987
Amortization of Net Actuarial Losses (Gains)	78		46		155	93
Amortization of Prior Service Credit	(16)		(15)		(32)	(32)
Defined Benefit Plans, Net	62		31		123	61
Other Comprehensive Income (Loss)	3,326		(6,537)		8,055	4,048
Other Comprehensive Income (Loss), Net of Tax:
Net Unrealized Gains (Losses) Arising During the Period	4,427		(23,215)		12,807	980
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	4,625		4,998		9,183	10,079
Net Unrealized Gains (Losses) on Investment Securities	9,052		(18,217)		21,990	11,059
Amortization of Net Actuarial Losses (Gains)	213		131		427	259
Amortization of Prior Service Credit	(45)		(47)		(90)	(91)
Defined Benefit Plans, Net	168		84		337	168
Total Other Comprehensive Income (Loss)	$ 9,220	$ 13,107	$ (18,133)	$ 29,360	$ 22,327	$ 11,227

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