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Loans (Performance of Loans that are Modified to Borrowers Experiencing Financial Difficulty) (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	$ 4,417,516	$ 4,411,057
Extended Maturity [Member]
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	1,393
Extended Maturity [Member] | Current
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	841
Extended Maturity [Member] | 30-89 Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	165
Extended Maturity [Member] | 90+ Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	387
Commercial Business [Member] | Extended Maturity [Member]
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Commercial Business [Member] | Extended Maturity [Member] | Current
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Commercial Business [Member] | Extended Maturity [Member] | 30-89 Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Commercial Business [Member] | Extended Maturity [Member] | 90+ Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Commercial Mortgage [Member] | Extended Maturity [Member]
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Commercial Mortgage [Member] | Extended Maturity [Member] | Current
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Commercial Mortgage [Member] | Extended Maturity [Member] | 30-89 Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Commercial Mortgage [Member] | Extended Maturity [Member] | 90+ Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Residential Real Estate Loans [Member] | Extended Maturity [Member]
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	1,393
Residential Real Estate Loans [Member] | Extended Maturity [Member] | Current
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	841
Residential Real Estate Loans [Member] | Extended Maturity [Member] | 30-89 Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	165
Residential Real Estate Loans [Member] | Extended Maturity [Member] | 90+ Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	387
Residential Real Estate Lines [Member] | Extended Maturity [Member]
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Residential Real Estate Lines [Member] | Extended Maturity [Member] | Current
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Residential Real Estate Lines [Member] | Extended Maturity [Member] | 30-89 Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Residential Real Estate Lines [Member] | Extended Maturity [Member] | 90+ Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Consumer Indirect [Member] | Extended Maturity [Member]
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Consumer Indirect [Member] | Extended Maturity [Member] | Current
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Consumer Indirect [Member] | Extended Maturity [Member] | 30-89 Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Consumer Indirect [Member] | Extended Maturity [Member] | 90+ Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Other Consumer [Member] | Extended Maturity [Member]
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Other Consumer [Member] | Extended Maturity [Member] | Current
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Other Consumer [Member] | Extended Maturity [Member] | 30-89 Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	0
Other Consumer [Member] | Extended Maturity [Member] | 90+ Days Past Due
Financing Receivable, Modified [Line Items]
Financing receivables, amortized cost basis	$ 0

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