Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net Income	$ 171,202	$ 225,804	$ 253,372
Other Comprehensive Income (Loss), Net of Tax:
Net Unrealized Gains (Losses) on Investment Securities	36,152	(376,694)	(83,958)
Defined Benefit Plans	1,818	8,418	9,754
Other Comprehensive Income (Loss)	37,970	(368,276)	(74,204)
Comprehensive Income (Loss)	$ 209,172	$ (142,472)	$ 179,168