Loans And Allowance For Credit Losses (Credit Quality Indicators Commercial Loan Portfolio) (Details) - Commercial Portfolio Segment [Member] $ in Thousands	Jun. 30, 2020 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	$ 3,060,688
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	2,445,062
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,219,953
Financing Receivable, Originated Three Years before Latest Fiscal Year	842,540
Financing Receivable, Originated Four Years before Latest Fiscal Year	654,470
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	700,464
Financing Receivable, Revolving	1,808,225
Financing Receivable, before Allowance for Credit Loss, Total	10,731,402
Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,274,088
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,328,799
Financing Receivable, Originated Two Years before Latest Fiscal Year	577,308
Financing Receivable, Originated Three Years before Latest Fiscal Year	394,141
Financing Receivable, Originated Four Years before Latest Fiscal Year	219,821
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	346,298
Financing Receivable, Revolving	1,717,762
Financing Receivable, before Allowance for Credit Loss, Total	6,858,217
Real Estate - Construction And Land [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	225,583
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	346,170
Financing Receivable, Originated Two Years before Latest Fiscal Year	146,692
Financing Receivable, Originated Three Years before Latest Fiscal Year	102,177
Financing Receivable, Originated Four Years before Latest Fiscal Year	43,265
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	28,421
Financing Receivable, Revolving	39,714
Financing Receivable, before Allowance for Credit Loss, Total	932,022
Real Estate - Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	561,017
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	770,093
Financing Receivable, Originated Two Years before Latest Fiscal Year	495,953
Financing Receivable, Originated Three Years before Latest Fiscal Year	346,222
Financing Receivable, Originated Four Years before Latest Fiscal Year	391,384
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	325,745
Financing Receivable, Revolving	50,749
Financing Receivable, before Allowance for Credit Loss, Total	2,941,163
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,913,221
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	2,373,766
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,184,546
Financing Receivable, Originated Three Years before Latest Fiscal Year	748,222
Financing Receivable, Originated Four Years before Latest Fiscal Year	607,181
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	641,676
Financing Receivable, Revolving	1,717,552
Financing Receivable, before Allowance for Credit Loss, Total	10,186,164
Pass [Member] | Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,203,632
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,267,837
Financing Receivable, Originated Two Years before Latest Fiscal Year	559,915
Financing Receivable, Originated Three Years before Latest Fiscal Year	389,807
Financing Receivable, Originated Four Years before Latest Fiscal Year	211,735
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	325,202
Financing Receivable, Revolving	1,631,883
Financing Receivable, before Allowance for Credit Loss, Total	6,590,011
Pass [Member] | Real Estate - Construction And Land [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	225,124
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	345,970
Financing Receivable, Originated Two Years before Latest Fiscal Year	135,951
Financing Receivable, Originated Three Years before Latest Fiscal Year	74,556
Financing Receivable, Originated Four Years before Latest Fiscal Year	43,265
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	28,420
Financing Receivable, Revolving	39,714
Financing Receivable, before Allowance for Credit Loss, Total	893,000
Pass [Member] | Real Estate - Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	484,465
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	759,959
Financing Receivable, Originated Two Years before Latest Fiscal Year	488,680
Financing Receivable, Originated Three Years before Latest Fiscal Year	283,859
Financing Receivable, Originated Four Years before Latest Fiscal Year	352,181
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	288,054
Financing Receivable, Revolving	45,955
Financing Receivable, before Allowance for Credit Loss, Total	2,703,153
Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	70,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	26,161
Financing Receivable, Originated Two Years before Latest Fiscal Year	25,690
Financing Receivable, Originated Three Years before Latest Fiscal Year	62,096
Financing Receivable, Originated Four Years before Latest Fiscal Year	24,825
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	5,021
Financing Receivable, Revolving	44,403
Financing Receivable, before Allowance for Credit Loss, Total	258,196
Special Mention [Member] | Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	51,188
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	21,671
Financing Receivable, Originated Two Years before Latest Fiscal Year	12,865
Financing Receivable, Originated Three Years before Latest Fiscal Year	968
Financing Receivable, Originated Four Years before Latest Fiscal Year	4,538
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	2,233
Financing Receivable, Revolving	44,319
Financing Receivable, before Allowance for Credit Loss, Total	137,782
Special Mention [Member] | Real Estate - Construction And Land [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	10,148
Financing Receivable, Originated Three Years before Latest Fiscal Year	14,465
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	24,613
Special Mention [Member] | Real Estate - Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	18,812
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	4,490
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,677
Financing Receivable, Originated Three Years before Latest Fiscal Year	46,663
Financing Receivable, Originated Four Years before Latest Fiscal Year	20,287
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	2,788
Financing Receivable, Revolving	84
Financing Receivable, before Allowance for Credit Loss, Total	95,801
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	74,371
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	44,647
Financing Receivable, Originated Two Years before Latest Fiscal Year	8,928
Financing Receivable, Originated Three Years before Latest Fiscal Year	32,126
Financing Receivable, Originated Four Years before Latest Fiscal Year	21,924
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	49,680
Financing Receivable, Revolving	34,410
Financing Receivable, before Allowance for Credit Loss, Total	266,086
Substandard [Member] | Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	16,370
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	39,097
Financing Receivable, Originated Two Years before Latest Fiscal Year	4,508
Financing Receivable, Originated Three Years before Latest Fiscal Year	3,270
Financing Receivable, Originated Four Years before Latest Fiscal Year	3,548
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	14,897
Financing Receivable, Revolving	29,700
Financing Receivable, before Allowance for Credit Loss, Total	111,390
Substandard [Member] | Real Estate - Construction And Land [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	459
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	200
Financing Receivable, Originated Two Years before Latest Fiscal Year	593
Financing Receivable, Originated Three Years before Latest Fiscal Year	13,156
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	14,408
Substandard [Member] | Real Estate - Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	57,542
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	5,350
Financing Receivable, Originated Two Years before Latest Fiscal Year	3,827
Financing Receivable, Originated Three Years before Latest Fiscal Year	15,700
Financing Receivable, Originated Four Years before Latest Fiscal Year	18,376
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	34,783
Financing Receivable, Revolving	4,710
Financing Receivable, before Allowance for Credit Loss, Total	140,288
Non-Accrual [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	3,096
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	488
Financing Receivable, Originated Two Years before Latest Fiscal Year	789
Financing Receivable, Originated Three Years before Latest Fiscal Year	96
Financing Receivable, Originated Four Years before Latest Fiscal Year	540
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	4,087
Financing Receivable, Revolving	11,860
Financing Receivable, before Allowance for Credit Loss, Total	20,956
Non-Accrual [Member] | Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,898
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	194
Financing Receivable, Originated Two Years before Latest Fiscal Year	20
Financing Receivable, Originated Three Years before Latest Fiscal Year	96
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	3,966
Financing Receivable, Revolving	11,860
Financing Receivable, before Allowance for Credit Loss, Total	19,034
Non-Accrual [Member] | Real Estate - Construction And Land [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	1
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	1
Non-Accrual [Member] | Real Estate - Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	198
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	294
Financing Receivable, Originated Two Years before Latest Fiscal Year	769
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	540
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	120
Financing Receivable, Revolving	0
Financing Receivable, before Allowance for Credit Loss, Total	$ 1,921