Loans And Allowance for Credit Losses (Credit Quality Indicators Personal Banking Loan Portfolio) (Details) - Personal Banking Portfolio Segment [Member] $ in Thousands	Sep. 30, 2020 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	$ 1,346,535
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	913,328
Financing Receivable, Originated Two Years before Latest Fiscal Year	426,987
Financing Receivable, Originated Three Years before Latest Fiscal Year	365,334
Financing Receivable, Originated Four Years before Latest Fiscal Year	338,630
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	702,738
Financing Receivable, Revolving	1,641,041
Financing Receivable, before Allowance for Credit Loss, Total	5,734,593
Real Estate - Personal [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	897,280
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	532,592
Financing Receivable, Originated Two Years before Latest Fiscal Year	238,643
Financing Receivable, Originated Three Years before Latest Fiscal Year	227,905
Financing Receivable, Originated Four Years before Latest Fiscal Year	248,232
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	597,994
Financing Receivable, Revolving	11,221
Financing Receivable, before Allowance for Credit Loss, Total	2,753,867
Consumer [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	446,985
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	380,736
Financing Receivable, Originated Two Years before Latest Fiscal Year	188,344
Financing Receivable, Originated Three Years before Latest Fiscal Year	137,429
Financing Receivable, Originated Four Years before Latest Fiscal Year	90,398
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	104,744
Financing Receivable, Revolving	657,724
Financing Receivable, before Allowance for Credit Loss, Total	2,006,360
Revolving Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	324,203
Financing Receivable, before Allowance for Credit Loss, Total	324,203
Consumer Credit Card [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	647,893
Financing Receivable, before Allowance for Credit Loss, Total	647,893
Overdrafts [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,270
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	2,270
Current to 90 Days Past Due
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,346,186
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	912,402
Financing Receivable, Originated Two Years before Latest Fiscal Year	426,278
Financing Receivable, Originated Three Years before Latest Fiscal Year	364,752
Financing Receivable, Originated Four Years before Latest Fiscal Year	337,990
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	700,179
Financing Receivable, Revolving	1,633,092
Financing Receivable, before Allowance for Credit Loss, Total	5,720,879
Current to 90 Days Past Due | Real Estate - Personal [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	897,007
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	532,003
Financing Receivable, Originated Two Years before Latest Fiscal Year	238,092
Financing Receivable, Originated Three Years before Latest Fiscal Year	227,499
Financing Receivable, Originated Four Years before Latest Fiscal Year	247,754
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	595,713
Financing Receivable, Revolving	11,221
Financing Receivable, before Allowance for Credit Loss, Total	2,749,289
Current to 90 Days Past Due | Consumer [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	446,909
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	380,399
Financing Receivable, Originated Two Years before Latest Fiscal Year	188,186
Financing Receivable, Originated Three Years before Latest Fiscal Year	137,253
Financing Receivable, Originated Four Years before Latest Fiscal Year	90,236
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	104,466
Financing Receivable, Revolving	656,700
Financing Receivable, before Allowance for Credit Loss, Total	2,004,149
Current to 90 Days Past Due | Revolving Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	323,809
Financing Receivable, before Allowance for Credit Loss, Total	323,809
Current to 90 Days Past Due | Consumer Credit Card [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	641,362
Financing Receivable, before Allowance for Credit Loss, Total	641,362
Current to 90 Days Past Due | Overdrafts [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,270
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	2,270
Over 90 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	349
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	731
Financing Receivable, Originated Two Years before Latest Fiscal Year	580
Financing Receivable, Originated Three Years before Latest Fiscal Year	537
Financing Receivable, Originated Four Years before Latest Fiscal Year	519
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,138
Financing Receivable, Revolving	7,949
Financing Receivable, before Allowance for Credit Loss, Total	11,803
Over 90 days past due | Real Estate - Personal [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	273
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	394
Financing Receivable, Originated Two Years before Latest Fiscal Year	422
Financing Receivable, Originated Three Years before Latest Fiscal Year	361
Financing Receivable, Originated Four Years before Latest Fiscal Year	357
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	860
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	2,667
Over 90 days past due | Consumer [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	76
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	337
Financing Receivable, Originated Two Years before Latest Fiscal Year	158
Financing Receivable, Originated Three Years before Latest Fiscal Year	176
Financing Receivable, Originated Four Years before Latest Fiscal Year	162
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	278
Financing Receivable, Revolving	1,024
Financing Receivable, before Allowance for Credit Loss, Total	2,211
Over 90 days past due | Revolving Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	394
Financing Receivable, before Allowance for Credit Loss, Total	394
Over 90 days past due | Consumer Credit Card [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	6,531
Financing Receivable, before Allowance for Credit Loss, Total	6,531
Over 90 days past due | Overdrafts [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	0
Non-Accrual [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	195
Financing Receivable, Originated Two Years before Latest Fiscal Year	129
Financing Receivable, Originated Three Years before Latest Fiscal Year	45
Financing Receivable, Originated Four Years before Latest Fiscal Year	121
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,421
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	1,911
Non-Accrual [Member] | Real Estate - Personal [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	195
Financing Receivable, Originated Two Years before Latest Fiscal Year	129
Financing Receivable, Originated Three Years before Latest Fiscal Year	45
Financing Receivable, Originated Four Years before Latest Fiscal Year	121
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,421
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	$ 1,911