Loans And Allowance For Credit Losses (Aging Information On Past Due And Accruing Loans) (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	$ 17,582,050	$ 17,093,789
30 - 89 Days Past Due	39,245	83,520
90 Days Past Due and Still Accruing	25,303	24,516
Non-accrual loans	18,870	18,278
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	17,665,468	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	6,328,684	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	1,405,398	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	3,757,778	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	3,058,845	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	2,157,867	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	364,429	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	576,151	595,930
Overdrafts
Loans And Allowance For Loan Losses [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Total	16,316	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	6,325,992	6,051,654
30 - 89 Days Past Due	1,168	1,501
90 Days Past Due and Still Accruing	1,114	564
Non-accrual loans	410	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	1,404,827	1,409,681
30 - 89 Days Past Due	145	0
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	426	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	3,742,041	3,640,643
30 - 89 Days Past Due	628	5,621
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	15,109	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	3,041,262	3,021,017
30 - 89 Days Past Due	5,053	25,267
90 Days Past Due and Still Accruing	11,582	10,885
Non-accrual loans	948	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	2,130,176	2,029,115
30 - 89 Days Past Due	23,700	40,398
90 Days Past Due and Still Accruing	3,991	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	360,725	351,056
30 - 89 Days Past Due	1,037	2,798
90 Days Past Due and Still Accruing	690	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	560,937	579,670
30 - 89 Days Past Due	7,288	7,622
90 Days Past Due and Still Accruing	7,926	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	16,090	10,953
30 - 89 Days Past Due	226	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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