Investment Securities (Investment Securities Pledged To Secure Borrowings And Public Deposits) (Details) $ in Thousands	Mar. 31, 2023 USD ($)
Investments, Debt and Equity Securities [Abstract]
To state and local government to secure public deposits, amortized cost	$ 1,659,206
To secure repurchased agreements, amortized cost	635,851
Other securities pledged, amortized cost	2,564,019
Total pledged securities, amortized cost	4,859,076
To state and local governments to secure public deposits, fair value	1,529,789
To secure repurchase agreements, fair value	577,667
Other securities pledged, fair value	2,375,610
Total pledged securities, fair value	$ 4,483,066