Investment Securities Available For Sale, at Fair Value - Schedule of Investment Securities Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value Option
Amortized Cost	$ 1,983,318	$ 81,788
Unrealized Gains	36,781	9,495
Unrealized Losses	(6,313)	(15,369)
Fair Value	2,013,786	75,914
CECL Securities
Amortized Cost	35	25,616
Unrealized Gains	0	0
Unrealized Losses	(4)	(1,971)
Fair Value	31	23,645
Amortized Cost
Amortized Cost	1,983,353	107,404
Unrealized Gains	36,781	9,495
Unrealized Losses	(6,317)	(17,340)
Fair Value	2,013,817	99,559
Agency RMBS
Fair Value Option
Amortized Cost	1,961,221	0
Unrealized Gains	30,135	0
Unrealized Losses	(2,032)	0
Fair Value	1,989,324	0
Agency RMBS \| Fixed rate
Fair Value Option
Amortized Cost	1,761,138	0
Unrealized Gains	21,581	0
Unrealized Losses	(1,829)	0
Fair Value	1,780,890	0
Agency RMBS \| Fixed rate \| Fannie Mae
Fair Value Option
Amortized Cost	1,084,702	0
Unrealized Gains	15,902	0
Unrealized Losses	(723)	0
Fair Value	1,099,881	0
Agency RMBS \| Fixed rate \| Freddie Mac
Fair Value Option
Amortized Cost	676,436	0
Unrealized Gains	5,679	0
Unrealized Losses	(1,106)	0
Fair Value	681,009	0
Agency RMBS \| Adjustable rate
Fair Value Option
Amortized Cost	147,460	0
Unrealized Gains	1,741	0
Unrealized Losses	0	0
Fair Value	149,201	0
Agency RMBS \| Adjustable rate \| Fannie Mae
Fair Value Option
Amortized Cost	110,036	0
Unrealized Gains	1,299	0
Unrealized Losses	0	0
Fair Value	111,335	0
Agency RMBS \| Adjustable rate \| Freddie Mac
Fair Value Option
Amortized Cost	37,424	0
Unrealized Gains	442	0
Unrealized Losses	0	0
Fair Value	37,866	0
Agency RMBS \| Interest-only
Fair Value Option
Amortized Cost	52,623	0
Unrealized Gains	6,813	0
Unrealized Losses	(203)	0
Fair Value	59,233	0
Agency RMBS \| Interest-only \| Ginnie Mae
Fair Value Option
Amortized Cost	52,623	0
Unrealized Gains	6,813	0
Unrealized Losses	(203)	0
Fair Value	59,233	0
Non-Agency RMBS
Fair Value Option
Amortized Cost	22,097	48,958
Unrealized Gains	6,646	9,436
Unrealized Losses	(4,281)	(13,469)
Fair Value	24,462	44,925
CECL Securities
Amortized Cost	35	25,616
Unrealized Gains	0	0
Unrealized Losses	(4)	(1,971)
Fair Value	31	23,645
CMBS
Fair Value Option
Amortized Cost	0	32,033
Unrealized Gains	0	0
Unrealized Losses	0	(1,900)
Fair Value	0	30,133
ABS
Fair Value Option
Amortized Cost	0	797
Unrealized Gains	0	59
Unrealized Losses	0	0
Fair Value	$ 0	$ 856

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
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-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
-SubTopic 10
-Name Accounting Standards Codification
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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
-SubTopic 30
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-Section 45
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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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