Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement Of Income And Comprehensive Income [Abstract]
Net Income	$ 46,842	$ 54,834
Other Comprehensive Income (Loss), Net of Tax:
Net Unrealized Gains (Losses) on Investment Securities	29,276	(180,124)
Defined Benefit Plans	84	353
Total Other Comprehensive Income (Loss)	29,360	(179,771)
Comprehensive Income (Loss)	$ 76,202	$ (124,937)