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v3.25.1

Mortgage-Backed Securities - Investment Type (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Trading and Available-for-sale [Abstract] |  |  |
Par Value |  | $ 8,599,616 | $ 7,817,400
Amortized Cost |  | 8,671,317 | 7,912,848
Non-Agency other, Amortized Cost |  | 941,016 | 1,009,016
Fair Value |  | 8,399,925 | 7,512,087
Gross Unrealized Gain |  | 3,286 | 3,283
Gross Unrealized Loss |  | (156,386) | (175,773)
Fair Value |  | 787,916 | 836,526
Amortized Cost |  | 7,730,301 | 6,903,832
Gross Unrealized Gain |  | 41,773 | 11,081
Gross Unrealized Loss |  | (160,065) | (239,352)
Fair Value |  | 7,612,009 | 6,675,561
Residential Mortgage Backed Securities [Member] | Agency MBS |  |  |
Debt Securities, Trading and Available-for-sale [Abstract] |  |  |
Par Value |  | 8,490,912 | 7,717,764
Amortized Cost |  | 8,452,828 | 7,695,409
Non-Agency other, Amortized Cost |  | 811,622 | 827,314
Fair Value |  | 8,185,832 | 7,302,238
Gross Unrealized Gain |  | 0 | 0
Gross Unrealized Loss |  | (150,332) | (167,248)
Fair Value |  | 661,290 | 660,066
Amortized Cost |  | 7,641,206 | 6,868,095
Gross Unrealized Gain |  | 41,660 | 11,081
Gross Unrealized Loss |  | (158,323) | (237,004)
Fair Value |  | 7,524,543 | 6,642,172
Commercial Mortgage Backed Securities [Member] | Agency MBS |  |  |
Debt Securities, Trading and Available-for-sale [Abstract] |  |  |
Par Value |  | 108,704 | 99,636
Amortized Cost |  | 109,578 | 99,848
Non-Agency other, Amortized Cost |  | 55,000 | 99,848
Fair Value |  | 106,429 | 95,463
Gross Unrealized Gain |  | 12 | 3
Gross Unrealized Loss |  | (3,271) | (4,388)
Fair Value |  | 51,741 | 95,463
Amortized Cost |  | 54,578 | 0
Gross Unrealized Gain |  | 110 | 0
Gross Unrealized Loss |  | 0 | 0
Fair Value |  | 54,688 | 0
Interest-Only-Strip [Member] |  |  |
Debt Securities, Trading and Available-for-sale [Abstract] |  |  |
Amortized Cost | [1] | 108,911 | 117,591
Non-Agency other, Amortized Cost |  | 74,394 | 81,854
Fair Value | [1] | 107,664 | 114,386
Gross Unrealized Gain |  | 3,274 | 3,280
Gross Unrealized Loss |  | (2,783) | (4,137)
Fair Value |  | 74,885 | 80,997
Amortized Cost |  | 34,517 | 35,737
Gross Unrealized Gain |  | 3 | 0
Gross Unrealized Loss |  | (1,742) | (2,348)
Fair Value |  | 32,778 | 33,389
Interest-Only-Strip [Member] | Agency Securities |  |  |
Debt Securities, Trading and Available-for-sale [Abstract] |  |  |
Par Value |  | 5,779,969 | 6,196,778
Interest-Only-Strip, Non-Agency CMBS [Member] |  |  |
Debt Securities, Trading and Available-for-sale [Abstract] |  |  |
Par Value |  | $ 2,050,104 | $ 2,450,398
[1] | (1) The notional balance for Agency CMBS IO and non-Agency CMBS IO was $5,779,969 and $2,050,104, respectively, as of March 31, 2025, and $6,196,778 and $2,450,398, respectively, as of December 31, 2024.

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