Shareholders' Equity - AOCI Components Pre Post & Tax Effect (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Other Comprehensive Income (Loss), Before Tax:
Net Unrealized Gains (Losses) Arising During the Period	$ (523,221)	$ (111,084)	$ 58,763
(Gain) Loss on Sale		(3,798)	(77)
Amortization of Unrealized Holding (Gains) Losses on Held-to-Maturity Securities	10,680	648	397
Net Unrealized Gains (Losses) on Investment Securities	(512,541)	(114,234)	59,083
Net Actuarial Gains (Losses) Arising During the Period	9,525	10,842	(8,187)
Amortization of Net Actuarial Losses (Gains)	2,175	2,676	2,318
Amortization of Prior Service Credit	(246)	(246)	(246)
Defined Benefit Plans, Net	11,454	13,272	(6,115)
Other Comprehensive Income (Loss)	(501,087)	(100,962)	52,968
Other Comprehensive Income (Loss), Tax Effect:
Net Unrealized Gains (Losses) Arising During the Period	(138,678)	(29,440)	15,600
(Gain) Loss on Sale		(1,007)	(50)
Amortization of Unrealized Holding (Gains) Losses on Held-to-Maturity Securities	2,831	171	105
Net Unrealized Gains (Losses) on Investment Securities	(135,847)	(30,276)	15,655
Net Actuarial Gains (Losses) Arising During the Period	2,525	2,874	(2,170)
Amortization of Net Actuarial Losses (Gains)	576	709	614
Amortization of Prior Service Credit	(65)	(65)	(65)
Defined Benefit Plans, Net	3,036	3,518	(1,621)
Other Comprehensive Income (Loss)	(132,811)	(26,758)	14,034
Other Comprehensive Income (Loss), Net of Tax:
Net Unrealized Gains (Losses) Arising During the Period	(384,543)	(81,644)	43,163
(Gain) Loss on Sale		(2,791)	(27)
Amortization of Unrealized Holding (Gains) Losses on Held-to-Maturity Securities	7,849	477	292
Net Unrealized Gains (Losses) on Investment Securities	(376,694)	(83,958)	43,428
Net Actuarial Gains (Losses) Arising During the Period	7,000	7,968	(6,017)
Amortization of Net Actuarial Losses (Gains)	1,599	1,967	1,704
Amortization of Prior Service Credit	(181)	(181)	(181)
Defined Benefit Plans, Net	8,418	9,754	(4,494)
Other Comprehensive Income (Loss)	$ (368,276)	$ (74,204)	$ 38,934