Allowance for Credit Losses (Collateral Dependent Loans and Leases) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 37,642,413	$ 37,441,951
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	19,631,173	19,454,480
Commercial real estate | Commercial Real Estate, Non-owner Occupied Term [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	6,557,768	6,482,940
Commercial real estate | Owner occupied term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	5,231,676	5,195,605
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	9,742,766	9,696,404
Commercial | Term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	5,544,450	5,536,765
Commercial | Lines of credit & other, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	2,491,557	2,430,127
Commercial | Leases & equipment finance, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	1,706,759	1,729,512
Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	8,079,305	8,095,332
Residential | Mortgage, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	6,128,884	6,157,166
Residential | Home equity loans & lines, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	1,950,421	$ 1,938,166
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	59,438
Residential Real Estate | Commercial real estate | Commercial Real Estate, Non-owner Occupied Term [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Residential Real Estate | Commercial real estate | Owner occupied term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Residential Real Estate | Commercial | Term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Residential Real Estate | Commercial | Lines of credit & other, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Residential Real Estate | Commercial | Leases & equipment finance, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Residential Real Estate | Residential | Mortgage, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	56,920
Residential Real Estate | Residential | Home equity loans & lines, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	2,518
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	38,453
Commercial Real Estate | Commercial real estate | Commercial Real Estate, Non-owner Occupied Term [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	5,290
Commercial Real Estate | Commercial real estate | Owner occupied term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	31,710
Commercial Real Estate | Commercial | Term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Commercial Real Estate | Commercial | Lines of credit & other, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	1,453
Commercial Real Estate | Commercial | Leases & equipment finance, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Commercial Real Estate | Residential | Mortgage, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Commercial Real Estate | Residential | Home equity loans & lines, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
General Business Assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	47,795
General Business Assets | Commercial real estate | Commercial Real Estate, Non-owner Occupied Term [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
General Business Assets | Commercial real estate | Owner occupied term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
General Business Assets | Commercial | Term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	16,952
General Business Assets | Commercial | Lines of credit & other, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	250
General Business Assets | Commercial | Leases & equipment finance, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	30,593
General Business Assets | Residential | Mortgage, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
General Business Assets | Residential | Home equity loans & lines, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	4,265
Other | Commercial real estate | Commercial Real Estate, Non-owner Occupied Term [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Other | Commercial real estate | Owner occupied term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Other | Commercial | Term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	4,265
Other | Commercial | Lines of credit & other, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Other | Commercial | Leases & equipment finance, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Other | Residential | Mortgage, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Other | Residential | Home equity loans & lines, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	149,951
Total | Commercial real estate | Commercial Real Estate, Non-owner Occupied Term [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	5,290
Total | Commercial real estate | Owner occupied term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	31,710
Total | Commercial | Term, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	21,217
Total | Commercial | Lines of credit & other, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	1,703
Total | Commercial | Leases & equipment finance, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	30,593
Total | Residential | Mortgage, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	56,920
Total | Residential | Home equity loans & lines, net
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 2,518