Investment Securities (Investment Securities Pledged To Secure Borrowings And Public Deposits) (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Investments, Debt and Equity Securities [Abstract]
To state and local government to secure public deposits, amortized cost	$ 1,505,158
To secure repurchased agreements, amortized cost	392,939
Other securities pledged, amortized cost	2,321,670
Total pledged securities, amortized cost	4,219,767
To state and local governments to secure public deposits, fair value	1,305,616
To secure repurchase agreements, fair value	348,187
Other securities pledged, fair value	2,081,880
Total pledged securities, fair value	$ 3,735,683