Loans And Allowance For Credit Losses (Aging Information On Past Due And Accruing Loans) (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	$ 17,053,186	$ 17,080,238
30 - 89 Days Past Due	72,010	96,065
90 Days Past Due and Still Accruing	18,566	21,864
Non-accrual loans	19,303	7,312
Total	17,163,065	17,205,479
Business
Loans And Allowance For Loan Losses [Line Items]
Total	6,090,724	6,019,036
Real estate - construction and land
Loans And Allowance For Loan Losses [Line Items]
Total	1,396,515	1,446,764
Real estate - business
Loans And Allowance For Loan Losses [Line Items]
Total	3,572,539	3,719,306
Real estate - personal
Loans And Allowance For Loan Losses [Line Items]
Total	3,055,182	3,026,041
Consumer
Loans And Allowance For Loan Losses [Line Items]
Total	2,145,609	2,077,723
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Total	331,381	319,894
Consumer credit card
Loans And Allowance For Loan Losses [Line Items]
Total	566,925	589,913
Overdrafts
Loans And Allowance For Loan Losses [Line Items]
Total	4,190	6,802
Commercial Portfolio Segment [Member] | Business
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	6,088,607	5,985,713
30 - 89 Days Past Due	1,048	29,087
90 Days Past Due and Still Accruing	565	614
Non-accrual loans	504	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	1,396,097	1,446,764
30 - 89 Days Past Due	418	0
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	0	0
Commercial Portfolio Segment [Member] | Real estate - business
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	3,556,541	3,714,579
30 - 89 Days Past Due	948	4,582
90 Days Past Due and Still Accruing	0	85
Non-accrual loans	15,050	60
Personal Banking Portfolio Segment [Member] | Real estate - personal
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	3,029,550	2,999,988
30 - 89 Days Past Due	16,598	14,841
90 Days Past Due and Still Accruing	7,262	9,559
Non-accrual loans	1,772	1,653
Personal Banking Portfolio Segment [Member] | Consumer
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	2,099,967	2,036,353
30 - 89 Days Past Due	43,084	38,217
90 Days Past Due and Still Accruing	2,558	3,153
Non-accrual loans	0	0
Personal Banking Portfolio Segment [Member] | Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	326,461	315,483
30 - 89 Days Past Due	2,184	1,564
90 Days Past Due and Still Accruing	759	870
Non-accrual loans	1,977	1,977
Personal Banking Portfolio Segment [Member] | Consumer credit card
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	552,432	574,805
30 - 89 Days Past Due	7,071	7,525
90 Days Past Due and Still Accruing	7,422	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	3,531	6,553
30 - 89 Days Past Due	659	249
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	$ 0	$ 0