Investment Securities (Summary Of Continuous Unrealized Loss Positions Of Available-For-Sale Security) (Details) - Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Unrealized Loss Position For - Unrealized Loss - Less than 12 Months	$ (665,000)	$ 0
Unrealized Loss Position For - Unrealized Loss - 12 Months or More	(7,000)	0
Unrealized Loss Position For - Unrealized Loss - Total	(672,000)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	5,846,000	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	52,000	0
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 5,898,000	$ 0