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		Mar. 31, 2024		Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities, debt maturities, within one year, Amortized Cost		$ 134,400		$ 105,389
Available-for-sale Securities, debt maturities, after one year through three years, Amortized Cost		153,908		184,975
Available-for-sale Securities, debt maturities, after three year through five years, Amortized Cost		26,315		38,462
Available-for-sale Securities, debt maturities, after five year through ten years, Amortized Cost		436,074		448,931
Available-for-sale Securities, debt maturities, after ten years, Amortized Cost		936,447		949,873
Available-for-sale Securities, Amortized Cost		1,687,144		1,727,630
Available-for-sale Securities, debt maturities, within one year, Fair Value		132,638	[1]	104,113
Available-for-sale Securities, debt maturities, after one year through three years, Fair Value		144,869		174,827
Available-for-sale Securities, debt maturities, after three year through five years, Fair Value		23,483		34,316
Available-for-sale Securities, debt maturities, after five year through ten years, fair value		384,607	[1]	398,624
Availably-for-sale Securities, debt maturities, after ten years, Fair Value		814,385	[1]	839,806
Available-for-sale Securities, debt maturities, Fair Value		1,499,982	[1]	1,551,686
Held-to-maturity Securities, debt maturities, after five through ten years, Amortized Cost		2,626,367		2,754,817
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		3,167,383		3,133,981
Held-to-maturity Securities, Amortized cost	[2]	5,793,750		5,888,798
Held-to-maturity Securities, debt maturities, after five through ten years, Fair Value		2,625,796		2,740,154
Held-to-maturity Securities, debt maturities, after ten years, Fair Value		3,167,150		3,112,022
Held-to-maturity Securities, debt maturities, Fair Value		$ 5,792,946		$ 5,852,176	[2]

[1] Due to the immaterial amount of income recognized on tax-exempt securities, yields were not calculated on a tax-equivalent basis.

[2] 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.