Loans And Allowance For Credit Losses (Summary Classification Of Held To Maturity Loan Portfolio) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	$ 16,535,522	$ 16,303,131
Business
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	5,704,467	5,661,725
Real estate - construction and land
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	1,437,419	1,361,095
Real estate - business
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	3,486,543	3,406,981
Real estate - personal
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	2,952,042	2,918,078
Consumer
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	2,094,389	2,059,088
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	295,478	297,207
Consumer credit card
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	558,669	584,000
Overdrafts
Loans And Allowance For Loan Losses [Line Items]
Held for Investment Loans	$ 6,515	$ 14,957