Loans And Allowance For Credit Losses (Aging Information On Past Due And Accruing Loans) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	$ 16,887,296	$ 16,229,187
30 - 89 Days Past Due	47,731	49,808
90 Days Past Due and Still Accruing	15,351	15,830
Non-accrual loans	6,161	8,306
Total	16,956,539	16,303,131
Business
Loans And Allowance For Loan Losses [Line Items]
Total	5,906,493	5,661,725
Real estate - construction and land
Loans And Allowance For Loan Losses [Line Items]
Total	1,451,783	1,361,095
Real estate - business
Loans And Allowance For Loan Losses [Line Items]
Total	3,621,222	3,406,981
Real estate - personal
Loans And Allowance For Loan Losses [Line Items]
Total	2,980,599	2,918,078
Consumer
Loans And Allowance For Loan Losses [Line Items]
Total	2,110,605	2,059,088
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Total	303,845	297,207
Consumer credit card
Loans And Allowance For Loan Losses [Line Items]
Total	574,755	584,000
Overdrafts
Loans And Allowance For Loan Losses [Line Items]
Total	7,237	14,957
Commercial Portfolio Segment [Member] | Business
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	5,896,412	5,652,710
30 - 89 Days Past Due	4,847	1,759
90 Days Past Due and Still Accruing	502	505
Non-accrual loans	4,732	6,751
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	1,451,314	1,361,095
30 - 89 Days Past Due	469	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	3,619,936	3,406,207
30 - 89 Days Past Due	1,133	585
90 Days Past Due and Still Accruing	0	0
Non-accrual loans	153	189
Personal Banking Portfolio Segment [Member] | Real estate - personal
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	2,962,174	2,895,742
30 - 89 Days Past Due	10,921	14,289
90 Days Past Due and Still Accruing	6,228	6,681
Non-accrual loans	1,276	1,366
Personal Banking Portfolio Segment [Member] | Consumer
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	2,087,542	2,031,827
30 - 89 Days Past Due	21,199	25,089
90 Days Past Due and Still Accruing	1,864	2,172
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	300,329	295,303
30 - 89 Days Past Due	2,676	1,201
90 Days Past Due and Still Accruing	840	703
Non-accrual loans	0	0
Personal Banking Portfolio Segment [Member] | Consumer credit card
Loans And Allowance For Loan Losses [Line Items]
Current or Less than 30 Days Past Due	562,657	572,213
30 - 89 Days Past Due	6,181	6,238
90 Days Past Due and Still Accruing	5,917	5,549
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	6,932	14,090
30 - 89 Days Past Due	305	647
90 Days Past Due and Still Accruing	0	220
Non-accrual loans	$ 0	$ 0