Available-for-Sale and Held-to-Maturity Securities (Schedule Of Amortized Cost And Fair Values Of Debt Securities By Contractual Maturity) (Details) - USD ($) $ in Thousands		Jun. 30, 2025	Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities, debt maturities, within one year, Amortized Cost		$ 54,646	$ 78,491
Available-for-sale Securities, debt maturities, after one year through three years, Amortized Cost		124,515	143,648
Available-for-sale Securities, debt maturities, after three year through five years, Amortized Cost		21,243	0
Available-for-sale Securities, debt maturities, after five year through ten years, Amortized Cost		382,457	395,884
Available-for-sale Securities, debt maturities, after ten years, Amortized Cost		1,093,185	1,136,686
Available-for-sale securities, Amortized cost		1,676,046	1,754,709
Available-for-sale Securities, debt maturities, within one year, Fair Value		54,345	78,080
Available-for-sale Securities, debt maturities, after one year through three years, Fair Value		120,628	137,049
Available-for-sale Securities, debt maturities, after three year through five years, Fair Value		19,193	0
Available-for-sale Securities, debt maturities, after five year through ten years, fair value		354,549	352,736
Availably-for-sale Securities, debt maturities, after ten years, Fair Value		997,677	1,016,733
Available-for-sale Securities, debt maturities, Fair Value		1,546,392	1,584,598
Held-to-maturity Securities, debt maturities, after three through five years, Amortized Cost		141,294	91,184
Held-to-maturity Securities, debt maturities, after five through ten years, Amortized Cost		2,509,599	3,063,278
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		3,934,032	3,370,492
Held-to-maturity securities, at amortized cost	[1]	6,584,925	6,524,954
Held-to-maturity Securities, debt maturities, after three through five years, Fair Value		141,647	91,238
Held-to-maturity Securities, debt maturities, after five through ten years, Fair Value		2,516,024	3,075,645
Held-to-maturity Securities, debt maturities, after ten years, Fair Value		3,944,792	3,380,764
Held-to-maturity Securities, debt maturities, Fair Value	[1]	$ 6,602,463	$ 6,547,647

[1] Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.