Stockholders' Equity (Components of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ (621,127)	$ (772,182)	$ (53,935)
Net change in unrealized gain (loss)	(65,141)	91,061	(898,241)
Reclassification of net (gain) loss realized and included in earnings	52,832	115,619	(5,947)
Valuation adjustments for employee benefit plans		(13,325)	(24,139)
Valuation Adjustments to Pension Plan attributable to VERIP and Curtailment	28,191
Amortization of unrealized net (gain) loss on securities transferred to held to maturity	1,670	1,747	1,355
Income tax (expense) benefit	(2,517)	(44,047)	208,725
Ending Balance	(606,092)	(621,127)	(772,182)
Accumulated Other Comprehensive Loss Available for Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(450,748)	(584,408)	11,037
Net change in unrealized gain (loss)	(31,119)	104,543	(785,538)
Reclassification of net (gain) loss realized and included in earnings		68,105	1,707
Transfer of net unrealized loss from AFS to HTM securities portfolio			15,405
Income tax (expense) benefit	8,188	(38,988)	172,981
Ending Balance	(473,679)	(450,748)	(584,408)
Held to Maturity Securities Transferred from AFS [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(9,385)	(10,734)	153
Transfer of net unrealized loss from AFS to HTM securities portfolio			(15,405)
Amortization of unrealized net (gain) loss on securities transferred to held to maturity	1,670	1,747	1,355
Income tax (expense) benefit	(356)	(398)	3,163
Ending Balance	(8,071)	(9,385)	(10,734)
Employee Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(103,061)	(97,952)	(80,946)
Reclassification of net (gain) loss realized and included in earnings	4,888	6,800	2,274
Valuation adjustments for employee benefit plans		(13,325)	(24,139)
Valuation Adjustments to Pension Plan attributable to VERIP and Curtailment	28,191
Income tax (expense) benefit	(7,253)	1,416	4,859
Ending Balance	(77,235)	(103,061)	(97,952)
Gains and Losses on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(58,306)	(79,093)	16,284
Net change in unrealized gain (loss)	(33,678)	(13,850)	(113,171)
Reclassification of net (gain) loss realized and included in earnings	47,944	40,714	(9,928)
Income tax (expense) benefit	(3,096)	(6,077)	27,722
Ending Balance	(47,136)	(58,306)	(79,093)
Equity Method Investment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	373	5	(463)
Net change in unrealized gain (loss)	(344)	368	468
Ending Balance	$ 29	$ 373	$ 5