Loans And Allowance For Credit Losses (Aging Information On Past Due And Accruing Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	$ 17,279,446	$ 17,093,789
30 - 89 Days Past Due	57,955	83,520
90 Days Past Due and Still Accruing	19,417	24,516
Non-accrual loans	22,603	18,278
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	17,379,421	17,220,103
Business Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	6,239,276	6,053,820
Real estate - construction and land
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	1,419,572	1,409,901
Business Real Estate Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	3,628,635	3,661,218
Personal Real Estate Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	3,047,809	3,058,195
Consumer Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	2,116,160	2,073,123
Revolving home equity
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	356,675	356,650
Credit Card Receivable [Member]
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	568,163	595,930
Overdrafts
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	3,131	11,266
Commercial Portfolio Segment [Member] \| Business Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	6,235,165	6,051,654
30 - 89 Days Past Due	2,386	1,501
90 Days Past Due and Still Accruing	613	564
Non-accrual loans	1,112	101
Commercial Portfolio Segment [Member] \| Real estate - construction and land
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	1,419,343	1,409,681
30 - 89 Days Past Due	9	0
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	220	220
Commercial Portfolio Segment [Member] \| Business Real Estate Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	3,610,277	3,640,643
30 - 89 Days Past Due	10	5,621
90 Days Past Due and Still Accruing	43	0
Non-accrual loans	18,305	14,954
Personal Banking Portfolio Segment [Member] \| Personal Real Estate Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	3,017,240	3,021,017
30 - 89 Days Past Due	22,556	25,267
90 Days Past Due and Still Accruing	7,024	10,885
Non-accrual loans	989	1,026
Personal Banking Portfolio Segment [Member] \| Consumer Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	2,089,260	2,029,115
30 - 89 Days Past Due	24,157	40,398
90 Days Past Due and Still Accruing	2,743	3,610
Non-accrual loans	0	0
Personal Banking Portfolio Segment [Member] \| Revolving home equity
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	353,166	351,056
30 - 89 Days Past Due	990	2,798
90 Days Past Due and Still Accruing	542	819
Non-accrual loans	1,977	1,977
Personal Banking Portfolio Segment [Member] \| Credit Card Receivable [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	552,121	579,670
30 - 89 Days Past Due	7,590	7,622
90 Days Past Due and Still Accruing	8,452	8,638
Non-accrual loans	0	0
Personal Banking Portfolio Segment [Member] \| Overdrafts
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	2,874	10,953
30 - 89 Days Past Due	257	313
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	$ 0	$ 0

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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