Investment Securities (Investment Securities Pledged To Secure Borrowings And Public Deposits) (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Investments, Debt and Equity Securities [Abstract]
To state and local government to secure public deposits, amortized cost	$ 1,800,912
To secure repurchased agreements, amortized cost	326,111
Other securities pledged, amortized cost	3,407,623
Total pledged securities, amortized cost	5,534,646
To state and local governments to secure public deposits, fair value	1,638,230
To secure repurchase agreements, fair value	297,673
Other securities pledged, fair value	3,139,037
Total pledged securities, fair value	$ 5,074,940