Investment Securities (Summary Of Net Gain From Sale Of Agency Securities) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Cost of Sale of Fair Value Option Securities	$ (12,652,000)	$ (9,499,000)	$ (21,089,000)	$ (12,904,000)
Cost of Sale of Investment Securities	(12,652,000)	(9,608,000)	(21,182,000)	(13,013,000)
Proceeds from Sale of Debt Securities	12,636,000	9,431,000	21,240,000	12,591,000
Proceeds from Sale of Debt Securities, Trading	12,636,000	9,336,000	21,153,000	12,496,000
Proceeds from Sale of Debt Securities, Available-for-sale	0	95,000	87,000	95,000
Net gain (loss) on sale of investment securities	(16,000)	(177,000)	58,000	(422,000)
Principal Payments Received on Available-For-Sale securities			221,000	273,000
Trading Securities [Member]
Trading Securities Par	84,686,000		84,686,000		$ 77,313,000
Available-for-sale Securities [Member]
Agency MBS sold, at cost	0	109,000	93,000	109,000
Net gain (loss) on sale of investment securities		(14,000)		(14,000)
Debt Securities, Available-for-sale, Realized Gain	0	0	0	0
Debt Securities, Available-for-sale, Realized Loss	0	14,000	6,000	14,000
Securities Remeasured at Fair Value [Member]
Net gain (loss) on sale of investment securities		(163,000)		(408,000)
Debt Securities, Available-for-sale, Realized Gain	30,000	12,000	125,000	33,000
Debt Securities, Available-for-sale, Realized Loss	46,000	175,000	61,000	441,000
Securities (Assets) [Member]
Net gain (loss) on sale of investment securities	(16,000)	(177,000)	58,000	(422,000)
Debt Securities, Available-for-sale, Realized Gain	30,000	12,000	125,000	33,000
Debt Securities, Available-for-sale, Realized Loss	46,000	$ 189,000	67,000	$ 455,000
Cost and Proceeds of Investment Securities [Member] \| Available-for-sale Securities [Member]
Net gain (loss) on sale of investment securities	0		(6,000)
Cost and Proceeds of Investment Securities [Member] \| Securities Remeasured at Fair Value [Member]
Net gain (loss) on sale of investment securities	(16,000)		64,000
Gross Gain & Loss of Investment Securities [Member] \| Available-for-sale Securities [Member]
Net gain (loss) on sale of investment securities	0		(6,000)
Gross Gain & Loss of Investment Securities [Member] \| Securities Remeasured at Fair Value [Member]
Net gain (loss) on sale of investment securities	(16,000)		64,000
Non-Agency [Member] \| Interest-Only-Strip \| Trading Securities [Member]
Trading Securities Par	16,000		16,000		16,000
Agency Securities [Member] \| Interest-Only-Strip \| Trading Securities [Member]
Trading Securities Par	$ 5,923,000		$ 5,923,000		$ 4,475,000

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