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Available-for-Sale and Held-to-Maturity Securities (Tables) | 6 Months Ended
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Jun. 30, 2025
Investments, Debt and Equity Securities [Abstract] |
Schedule of Amortized Cost and Fair Values of Available for Sale Securities and Held to Maturity Securities | The following tables provide a summary of the amortized cost and fair values of the available-for-sale securities and held-to-maturity securities at June 30, 2025 and December 31, 2024 (in thousands):
|  | June 30, 2025 |
|  | Amortized Cost |  |  | Gross Unrealized Gains (1) |  |  | Gross Unrealized Losses (1) |  |  | Fair Value |
Available-for-sale securities |  |  |  |  |  |  |  |  |  |  |  |
U.S. government agency securities |  | $ | 2,424 |  |  | $ | 6 |  |  | $ | (92 | ) |  | $ | 2,338 |
State and municipal securities |  |  | 2,350 |  |  |  | — |  |  |  | — |  |  |  | 2,350 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |
Agency |  |  | 1,046,390 |  |  |  | 2,166 |  |  |  | (100,397 | ) |  |  | 948,159 |
Commercial |  |  | 42,050 |  |  |  | — |  |  |  | (394 | ) |  |  | 41,656 |
Non-agency |  |  | 175 |  |  |  | — |  |  |  | (7 | ) |  |  | 168 |
Corporate fixed income securities |  |  | 464,556 |  |  |  | 172 |  |  |  | (30,591 | ) |  |  | 434,137 |
Asset-backed securities |  |  | 118,101 |  |  |  | 67 |  |  |  | (584 | ) |  |  | 117,584 |
|  | $ | 1,676,046 |  |  | $ | 2,411 |  |  | $ | (132,065 | ) |  | $ | 1,546,392 |
Held-to-maturity securities (2) |  |  |  |  |  |  |  |  |  |  |  |
Asset-backed securities |  | $ | 6,584,925 |  |  | $ | 20,747 |  |  | $ | (3,209 | ) |  | $ | 6,602,463 |
|  | December 31, 2024 |
|  | Amortized Cost |  |  | Gross Unrealized Gains (1) |  |  | Gross Unrealized Losses (1) |  |  | Fair Value |
Available-for-sale securities |  |  |  |  |  |  |  |  |  |  |  |
U.S. government agency securities |  | $ | 2,407 |  |  | $ | — |  |  | $ | (141 | ) |  | $ | 2,266 |
State and municipal securities |  |  | 2,350 |  |  |  | — |  |  |  | (1 | ) |  |  | 2,349 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |
Agency |  |  | 1,045,344 |  |  |  | 334 |  |  |  | (124,115 | ) |  |  | 921,563 |
Commercial |  |  | 69,430 |  |  |  | — |  |  |  | (1,474 | ) |  |  | 67,956 |
Non-agency |  |  | 206 |  |  |  | — |  |  |  | (7 | ) |  |  | 199 |
Corporate fixed income securities |  |  | 507,824 |  |  |  | — |  |  |  | (43,832 | ) |  |  | 463,992 |
Asset-backed securities |  |  | 127,148 |  |  |  | 202 |  |  |  | (1,077 | ) |  |  | 126,273 |
|  | $ | 1,754,709 |  |  | $ | 536 |  |  | $ | (170,647 | ) |  | $ | 1,584,598 |
Held-to-maturity securities (2) |  |  |  |  |  |  |  |  |  |  |  |
Asset-backed securities |  | $ | 6,524,954 |  |  | $ | 26,498 |  |  | $ | (3,805 | ) |  | $ | 6,547,647 |
(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.
Schedule of Amortized Cost and Fair Values of Debt Securities by Contractual Maturity | The table below summarizes the amortized cost and fair values of our securities by contractual maturity at June 30, 2025 and December 31, 2024 (in thousands). Expected maturities may differ significantly from contractual maturities, as issuers may have the right to call or prepay obligations with or without call or prepayment penalties.
|  | June 30, 2025 |  |  | December 31, 2024 |
|  | Amortized Cost |  |  | Fair Value |  |  | Amortized Cost |  |  | Fair Value |
Available-for-sale securities |  |  |  |  |  |  |  |  |  |  |  |
Within one year |  | $ | 54,646 |  |  | $ | 54,345 |  |  | $ | 78,491 |  |  | $ | 78,080 |
After one year through three years |  |  | 124,515 |  |  |  | 120,628 |  |  |  | 143,648 |  |  |  | 137,049 |
After three years through five years |  |  | 21,243 |  |  |  | 19,193 |  |  |  | — |  |  |  | — |
After five years through ten years |  |  | 382,457 |  |  |  | 354,549 |  |  |  | 395,884 |  |  |  | 352,736 |
After ten years |  |  | 1,093,185 |  |  |  | 997,677 |  |  |  | 1,136,686 |  |  |  | 1,016,733 |
|  | $ | 1,676,046 |  |  | $ | 1,546,392 |  |  | $ | 1,754,709 |  |  | $ | 1,584,598 |
Held-to-maturity securities |  |  |  |  |  |  |  |  |  |  |  |
After three years through five years |  |  | 141,294 |  |  |  | 141,647 |  |  |  | 91,184 |  |  |  | 91,238 |
After five years through ten years |  |  | 2,509,599 |  |  |  | 2,516,024 |  |  |  | 3,063,278 |  |  |  | 3,075,645 |
After ten years |  |  | 3,934,032 |  |  |  | 3,944,792 |  |  |  | 3,370,492 |  |  |  | 3,380,764 |
|  | $ | 6,584,925 |  |  | $ | 6,602,463 |  |  | $ | 6,524,954 |  |  | $ | 6,547,647 |
Schedule of Contractual Maturities | The maturities of our available-for-sale (fair value) and held-to-maturity (amortized cost) securities at June 30, 2025, are as follows (in thousands):
|  | Within 1 Year |  |  | 1-5 Years |  |  | 5-10 Years |  |  | After 10 Years |  |  | Total |
Available-for-sale securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government agency securities |  | $ | — |  |  | $ | 2,338 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,338 |
State and municipal securities |  |  | — |  |  |  | 2,350 |  |  |  | — |  |  |  | — |  |  |  | 2,350 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency |  |  | — |  |  |  | 136 |  |  |  | 84,568 |  |  |  | 863,455 |  |  |  | 948,159 |
Commercial |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 41,656 |  |  |  | 41,656 |
Non-agency |  |  | — |  |  |  | — |  |  |  | 168 |  |  |  | — |  |  |  | 168 |
Corporate fixed income securities |  |  | 54,345 |  |  |  | 134,997 |  |  |  | 244,795 |  |  |  | — |  |  |  | 434,137 |
Asset-backed securities |  |  | — |  |  |  | — |  |  |  | 25,018 |  |  |  | 92,566 |  |  |  | 117,584 |
|  | $ | 54,345 |  |  | $ | 139,821 |  |  | $ | 354,549 |  |  | $ | 997,677 |  |  | $ | 1,546,392 |
Held-to-maturity securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Asset-backed securities |  | $ | — |  |  | $ | 141,294 |  |  | $ | 2,509,599 |  |  | $ | 3,934,032 |  |  | $ | 6,584,925 |
Schedule of Gross Unrealized Losses and Estimated Fair Value by Length of Time | The following table shows the gross unrealized losses and fair value of the Company’s investment securities with unrealized losses, aggregated by investment category and length of time the individual investment securities have been in continuous unrealized loss positions, at June 30, 2025 (in thousands):
|  | Less than 12 months |  |  | 12 months or more |  |  | Total |
|  | Gross Unrealized Losses |  |  | Fair Value |  |  | Gross Unrealized Losses |  |  | Fair Value |  |  | Gross Unrealized Losses |  |  | Fair Value |
Available-for-sale securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government agency securities |  | $ | — |  |  | $ | — |  |  | $ | (92 | ) |  | $ | 1,870 |  |  | $ | (92 | ) |  | $ | 1,870 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency |  |  | (530 | ) |  |  | 53,565 |  |  |  | (99,867 | ) |  |  | 617,052 |  |  |  | (100,397 | ) |  |  | 670,617 |
Commercial |  |  | — |  |  |  | — |  |  |  | (394 | ) |  |  | 41,656 |  |  |  | (394 | ) |  |  | 41,656 |
Non-agency |  |  | — |  |  |  | — |  |  |  | (7 | ) |  |  | 168 |  |  |  | (7 | ) |  |  | 168 |
Corporate fixed income securities |  |  | — |  |  |  | — |  |  |  | (30,591 | ) |  |  | 413,966 |  |  |  | (30,591 | ) |  |  | 413,966 |
Asset-backed securities |  |  | (75 | ) |  |  | 24,402 |  |  |  | (509 | ) |  |  | 53,844 |  |  |  | (584 | ) |  |  | 78,246 |
|  | $ | (605 | ) |  | $ | 77,967 |  |  | $ | (131,460 | ) |  | $ | 1,128,556 |  |  | $ | (132,065 | ) |  | $ | 1,206,523 |
Schedule of Amortized Cost of Held-to-Maturity Securities by Credit Quality Indicator | The following table shows the amortized cost of our held-to-maturity securities by credit quality indicator at June 30, 2025 (in thousands):
|  | AAA |  |  | AA |  |  | C |  |  | Total |
Held-to-maturity securities |  |  |  |  |  |  |  |  |  |  |  |
Asset-backed securities |  | $ | 3,476,591 |  |  | $ | 3,107,987 |  |  | $ | 347 |  |  | $ | 6,584,925 |

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