Comprehensive Income/Loss (Comprised of the following Components) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ (114,827)	$ (163,084)
Net change in other comprehensive income (loss)	(4,511)	27,139
Ending Balance	(119,338)	(135,945)
Unrealized Gain (Loss) on Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(96,231)	(128,657)
Net change in other comprehensive income (loss)	(3,008)	17,068
Ending Balance	(99,239)	(111,589)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(20,575)	(36,630)
Net change in other comprehensive income (loss)	(1,488)	10,163
Ending Balance	(22,063)	(26,467)
Defined Benefit Postretirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	1,979	2,203
Net change in other comprehensive income (loss)	(15)	(92)
Ending Balance	1,964	2,111
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net change in other comprehensive income (loss)	$ (4,511)	$ 27,139