Stockholders' Equity (Line Items in Consolidated Income Statements Affected by Amounts Reclassified from Accumulated Other Comprehensive Income) (Details) - Reclassification out of Accumulated Other Comprehensive Income [Member] - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications, net of tax	[1]	$ 2,301	$ (1,183)
Accumulated Other Comprehensive Loss Available for Sale Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss on sale of AFS securities	[1]	(1,707)
Tax effect	[1]	385
Net of tax	[1]	(1,322)
Held to Maturity Securities Transferred from AFS [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of unrealized net gain (loss) on securities transferred to HTM	[1]	(261)	56
Tax effect	[1]	59	(13)
Net of tax	[1]	(202)	43
Employee Benefit Plans [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of defined benefit pension and post-retirement items	[1]	(1,209)	(1,954)
Tax effect	[1]	273	439
Net of tax	[1]	(936)	(1,515)
Gains and Losses on Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification of unrealized gain on cash flow hedges	[1]	3,875	6,136
Tax effect	[1]	(875)	(1,379)
Net of tax	[1]	3,000	4,757
Amortization of gain (loss) on terminated cash flow hedges	[1]	2,879
Tax effect	[1]	(650)
Net of tax	[1]	2,229
Gains and Losses on Equity Method Investment [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification of unrealized loss on equity method investment	[1]	(468)	(4,468)
Net of tax	[1]	$ (468)	$ (4,468)

[1] Amounts in parentheses indicate reduction in net income.