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Available-for-Sale and Held-to-Maturity Securities (Schedule of Amortized Cost and Fair Values of Available for Sale Securities and Held to Maturity Securities) (Details) - USD ($)
$ in Thousands

Sep. 30, 2025

Dec. 31, 2024

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

$ 1,802,058

$ 1,754,709

Available for sale securities, Gross unrealized gains

^[1]

3,767

536

Available-for-sale securities, Gross unrealized losses

^[1]

(117,189)

(170,647)

Available-for-sale securities, at fair value

1,688,636

1,584,598

Held-to-maturity securities, at amortized cost

^[2]

6,458,002

6,524,954

Held-to-maturity Securities, Gross unrealized gains

^[1],[2]

21,706

26,498

Held-to-maturity Securities, Gross unrealized losses

^[1],[2]

(2,690)

(3,805)

Held-to-maturity securities, Estimated fair value

^[2]

6,477,018

6,547,647

U.S. Government Agency Securities [Member]

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

2,432

2,407

Available for sale securities, Gross unrealized gains

^[1]

6

0

Available-for-sale securities, Gross unrealized losses

^[1]

(77)

(141)

Available-for-sale securities, at fair value

2,361

2,266

State and Municipal Securities [Member]

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

2,350

2,350

Available for sale securities, Gross unrealized gains

^[1]

1

0

Available-for-sale securities, Gross unrealized losses

^[1]

0

(1)

Available-for-sale securities, at fair value

2,351

2,349

Mortgage-Backed Securities [Member] | Agency Securities [Member]

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

1,239,648

1,045,344

Available for sale securities, Gross unrealized gains

^[1]

3,662

334

Available-for-sale securities, Gross unrealized losses

^[1]

(90,350)

(124,115)

Available-for-sale securities, at fair value

1,152,960

921,563

Mortgage-Backed Securities [Member] | Commercial [Member]

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

11,097

69,430

Available for sale securities, Gross unrealized gains

^[1]

0

0

Available-for-sale securities, Gross unrealized losses

^[1]

(121)

(1,474)

Available-for-sale securities, at fair value

10,976

67,956

Mortgage-Backed Securities [Member] | Non-Agency [Member]

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

164

206

Available for sale securities, Gross unrealized gains

^[1]

0

0

Available-for-sale securities, Gross unrealized losses

^[1]

(6)

(7)

Available-for-sale securities, at fair value

158

199

Corporate Fixed Income Securities [Member]

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

433,163

507,824

Available for sale securities, Gross unrealized gains

^[1]

35

0

Available-for-sale securities, Gross unrealized losses

^[1]

(25,846)

(43,832)

Available-for-sale securities, at fair value

407,352

463,992

Asset-Backed Securities [Member]

Schedule Of Available For Sale And Held To Maturity Securities [Line Items]

Available-for-sale securities, Amortized cost

113,204

127,148

Available for sale securities, Gross unrealized gains

^[1]

63

202

Available-for-sale securities, Gross unrealized losses

^[1]

(789)

(1,077)

Available-for-sale securities, at fair value

112,478

$ 126,273

Held-to-maturity securities, at amortized cost

$ 6,458,002

[1]	Unrealized gains/(losses) related to available-for-sale securities are reported in accumulated other comprehensive loss.
[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.

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