Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Accumulated other comprehensive income (loss), beginning balance			$ (119,171)
Net other comprehensive income (loss)	$ 11,121	$ 29,168	34,343	$ 23,995
Accumulated other comprehensive income (loss), ending balance	(84,828)		(84,828)
Net Unrealized Gains (Losses) on AFS Securities
Accumulated other comprehensive income (loss), beginning balance	(87,677)	(126,830)	(102,439)	(116,591)
Other comprehensive income (loss) before reclassifications	9,577	30,254	24,339	20,015
Amounts reclassed from accumulated other comprehensive income (loss)	0	0	0	0
Net other comprehensive income (loss)	9,577	30,254	24,339	20,015
Accumulated other comprehensive income (loss), ending balance	(78,100)	(96,576)	(78,100)	(96,576)
Net Unrealized Losses on Cash Flow Hedges
Accumulated other comprehensive income (loss), beginning balance	(6,269)	(10,599)	(7,938)	(15,619)
Other comprehensive income (loss) before reclassifications	42	(2,358)	(1,180)	210
Amounts reclassed from accumulated other comprehensive income (loss)	1,480	1,250	4,371	3,702
Net other comprehensive income (loss)	1,522	(1,108)	3,191	3,912
Accumulated other comprehensive income (loss), ending balance	(4,747)	(11,707)	(4,747)	(11,707)
Net Unrealized Losses on Defined Benefit Plan Obligations
Accumulated other comprehensive income (loss), beginning balance	(2,003)	(8,897)	(8,794)	(8,943)
Other comprehensive income (loss) before reclassifications	0	0	1,937	0
Amounts reclassed from accumulated other comprehensive income (loss)	22	22	4,876	68
Net other comprehensive income (loss)	22	22	6,813	68
Accumulated other comprehensive income (loss), ending balance	(1,981)	(8,875)	(1,981)	(8,875)
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), beginning balance	(95,949)	(146,326)	(119,171)	(141,153)
Other comprehensive income (loss) before reclassifications	9,619	27,896	25,096	20,225
Amounts reclassed from accumulated other comprehensive income (loss)	1,502	1,272	9,247	3,770
Net other comprehensive income (loss)	11,121	29,168	34,343	23,995
Accumulated other comprehensive income (loss), ending balance	$ (84,828)	$ (117,158)	$ (84,828)	$ (117,158)

- Definition

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

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- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

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