Other Comprehensive Income (Loss) (Component Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax	$ 398
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, after Tax	0	$ 0
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Reclassification Adjustments, after Tax	(518)	12,361
Other comprehensive loss before reclassifications	(518)	12,361
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax	(204)	12,361
Other comprehensive income (loss)	(204)	12,361
Changes in pension plan assets and benefit obligations, Net-of-tax amount	1,692	(6,680)	$ (1,692)	$ 6,680
Unrealized gains on available-for-sale securities, Net-of-tax amount	(68,087)	(83,353)	(67,883)	(95,714)
Total accumulated other comprehensive income (loss), Net-of-tax amount	(66,395)	(90,033)	$ (66,191)	$ (102,394)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	314	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	$ 314	$ 0