Loans And Allowance For Credit Losses (Aging Information On Past Due And Accruing Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	$ 16,979,276	$ 17,080,238
30 - 89 Days Past Due	70,319	96,065
90 Days Past Due and Still Accruing	21,986	21,864
Non-accrual loans	18,419	7,312
Total	17,090,000	17,205,479
Business Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Total	6,048,328	6,019,036
Real estate – construction and land
Loans And Allowance For Loan Losses [Line Items]
Total	1,381,607	1,446,764
Business Real Estate Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Total	3,586,999	3,719,306
Personal Real Estate Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Total	3,043,391	3,026,041
Consumer Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Total	2,108,281	2,077,723
Revolving home equity
Loans And Allowance For Loan Losses [Line Items]
Total	342,376	319,894
Credit Card Receivable [Member]
Loans And Allowance For Loan Losses [Line Items]
Total	574,746	589,913
Overdrafts
Loans And Allowance For Loan Losses [Line Items]
Total	4,272	6,802
Commercial Portfolio Segment [Member] | Business Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	6,041,090	5,985,713
30 - 89 Days Past Due	6,388	29,087
90 Days Past Due and Still Accruing	496	614
Non-accrual loans	354	3,622
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	1,381,108	1,446,764
30 - 89 Days Past Due	499	0
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	0	0
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	3,563,683	3,714,579
30 - 89 Days Past Due	8,372	4,582
90 Days Past Due and Still Accruing	0	85
Non-accrual loans	14,944	60
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	3,016,598	2,999,988
30 - 89 Days Past Due	17,048	14,841
90 Days Past Due and Still Accruing	8,601	9,559
Non-accrual loans	1,144	1,653
Personal Banking Portfolio Segment [Member] | Consumer Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	2,076,058	2,036,353
30 - 89 Days Past Due	28,424	38,217
90 Days Past Due and Still Accruing	3,799	3,153
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	337,653	315,483
30 - 89 Days Past Due	1,711	1,564
90 Days Past Due and Still Accruing	1,035	870
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	559,056	574,805
30 - 89 Days Past Due	7,635	7,525
90 Days Past Due and Still Accruing	8,055	7,583
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	4,030	6,553
30 - 89 Days Past Due	242	249
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	$ 0	$ 0