Investment Securities Available For Sale, at Fair Value - Schedule of Investment Securities Available for Sale (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Fair Value Option
Amortized Cost	$ 3,886,897,000	$ 1,983,318,000
Unrealized Gains	18,959,000	36,781,000
Unrealized Losses	(77,312,000)	(6,313,000)
Fair Value	3,828,544,000	2,013,786,000
CECL Securities
Amortized Cost	0	35,000
Unrealized Gains	0	0
Unrealized Losses	0	(4,000)
Fair Value	0	31,000
Total CECL Securities and Fair Value Option
Amortized Cost	3,886,897,000	1,983,353,000
Unrealized Gains	18,959,000	36,781,000
Unrealized Losses	(77,312,000)	(6,317,000)
Fair Value	3,828,544,000	2,013,817,000
Agency RMBS
Fair Value Option
Amortized Cost	3,163,035,000	1,961,221,000
Unrealized Gains	12,861,000	30,135,000
Unrealized Losses	(39,084,000)	(2,032,000)
Fair Value	3,136,812,000	1,989,324,000
Agency RMBS \| Fixed rate
Fair Value Option
Amortized Cost	2,949,038,000	1,761,138,000
Unrealized Gains	11,733,000	21,581,000
Unrealized Losses	(21,711,000)	(1,829,000)
Fair Value	2,939,060,000	1,780,890,000
Agency RMBS \| Fixed rate \| Fannie Mae
Fair Value Option
Amortized Cost	1,483,619,000	1,084,702,000
Unrealized Gains	7,819,000	15,902,000
Unrealized Losses	(7,991,000)	(723,000)
Fair Value	1,483,447,000	1,099,881,000
Agency RMBS \| Fixed rate \| Freddie Mac
Fair Value Option
Amortized Cost	1,465,419,000	676,436,000
Unrealized Gains	3,914,000	5,679,000
Unrealized Losses	(13,720,000)	(1,106,000)
Fair Value	1,455,613,000	681,009,000
Agency RMBS \| Adjustable rate
Fair Value Option
Amortized Cost	130,119,000	147,460,000
Unrealized Gains	285,000	1,741,000
Unrealized Losses	(822,000)	0
Fair Value	129,582,000	149,201,000
Agency RMBS \| Adjustable rate \| Fannie Mae
Fair Value Option
Amortized Cost	97,267,000	110,036,000
Unrealized Gains	265,000	1,299,000
Unrealized Losses	(631,000)	0
Fair Value	96,901,000	111,335,000
Agency RMBS \| Adjustable rate \| Freddie Mac
Fair Value Option
Amortized Cost	32,852,000	37,424,000
Unrealized Gains	20,000	442,000
Unrealized Losses	(191,000)	0
Fair Value	32,681,000	37,866,000
Agency RMBS \| Interest-only
Fair Value Option
Amortized Cost	83,878,000	52,623,000
Unrealized Gains	843,000	6,813,000
Unrealized Losses	(16,551,000)	(203,000)
Fair Value	68,170,000	59,233,000
Agency RMBS \| Interest-only \| Freddie Mac
Fair Value Option
Amortized Cost	5,251,000	0
Unrealized Gains	0	0
Unrealized Losses	(459,000)	0
Fair Value	4,792,000	0
Agency RMBS \| Interest-only \| Ginnie Mae
Fair Value Option
Amortized Cost	78,627,000	52,623,000
Unrealized Gains	843,000	6,813,000
Unrealized Losses	(16,092,000)	(203,000)
Fair Value	63,378,000	59,233,000
Non-Agency RMBS
Fair Value Option
Amortized Cost	66,203,000	22,097,000
Unrealized Gains	6,098,000	6,646,000
Unrealized Losses	(2,614,000)	(4,281,000)
Fair Value	69,687,000	24,462,000
CECL Securities
Amortized Cost	0	35,000
Unrealized Gains	0	0
Unrealized Losses	0	(4,000)
Fair Value	0	31,000
U.S. Treasury securities
Fair Value Option
Amortized Cost	657,659,000	0
Unrealized Gains	0	0
Unrealized Losses	(35,614,000)	0
Fair Value	$ 622,045,000	$ 0

Debt Securities, Available-For-Sale, CECL And Fair Value Option, Amortized Cost

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Total Debt Securities, Available for Sale, CECL and Fair Value [Abstract]

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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