Loans And Allowance For Credit Losses (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Accrued Interest Receivable	$ 46,200,000	$ 46,200,000	$ 25,900,000
Pledged Financial Instruments, Not Separately Reported, Loans Receivable, for Federal Home Loan Bank Debt	3,100,000,000	3,100,000,000
Pledged Financial Instruments, Not Separately Reported, Loans Receivable, for Federal Reserve Bank Debt	1,300,000,000	$ 1,300,000,000
Period after which loans are deemed in default (in days)		90 days
Effect on Interest Income Resulting From Modification to Credit Card Loans		$ (663,000)
Commitments to lend additional funds to customers with restructured loans	22,000,000	22,000,000
Letters of Credit to Customers with Substandard Risk Rating	24,000,000	24,000,000
Residential mortgage loans held for sale	1,426,000	1,426,000	5,570,000
Unpaid Principal Balance on Personal Real Estate Loans Held for Sale	1,500,000	1,500,000
Student Loans Held for Sale, Lower of Cost or Fair Value	6,600,000	6,600,000
HFS Loans on non accrual status	0	0
HFS loans 90 days past due and still accruing	0	0
Foreclosed real estate	354,000	354,000	115,000
Personal property acquired in repossession	1,700,000	1,700,000	1,100,000
Business
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Nonaccrual, No Allowance	4,100,000	4,100,000	$ 5,300,000
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Accrued Interest, Writeoff	48,000	103,000
Personal Banking Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Accrued Interest, Writeoff	$ 699,000	$ 2,400,000