Accumulated Other Comprehensive Income (Loss) - AOCI Components Pre Post & Tax Effect (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Other Comprehensive Income (Loss), Before Tax:
Net Unrealized Gains (Losses) Arising During the Period	$ 11,404	$ 32,918
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	6,202	6,913
Net Unrealized Gains (Losses) on Investment Securities	17,606	39,831
Amortization of Net Actuarial Losses (Gains)	291	175
Amortization of Prior Service Credit	(61)	(61)
Defined Benefit Plans, Net	230	114
Other Comprehensive Income (Loss)	17,836	39,945
Other Comprehensive Income (Loss), Tax Effect:
Net Unrealized Gains (Losses) Arising During the Period	3,024	8,723
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	1,644	1,832
Net Unrealized Gains (Losses) on Investment Securities	4,668	10,555
Amortization of Net Actuarial Losses (Gains)	77	47
Amortization of Prior Service Credit	(16)	(17)
Defined Benefit Plans, Net	61	30
Other Comprehensive Income (Loss)	4,729	10,585
Other Comprehensive Income (Loss), Net of Tax:
Net Unrealized Gains (Losses) Arising During the Period	8,380	24,195
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	4,558	5,081
Net Unrealized Gains (Losses) on Investment Securities	12,938	29,276
Amortization of Net Actuarial Losses (Gains)	214	128
Amortization of Prior Service Credit	(45)	(44)
Defined Benefit Plans, Net	169	84
Total Other Comprehensive Income	$ 13,107	$ 29,360

Net unrealized gain loss on investment securities net of tax.

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