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Residential Whole Loans - Additional Credit Related Information (Details) - Residential whole loans - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Gross write-offs	$ 1,036	$ 616	$ 5,262	$ 379
Non-QM loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,845,752				$ 4,845,752	$ 4,291,086
Gross write-offs	0	0	0	0
Business purpose loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total	2,898,559				2,898,559	3,396,181
Legacy RPL/NPL loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total	1,033,705				1,033,705	1,082,549
Gross write-offs	14	$ 180	$ 170	$ 22
Carrying Value
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	42,836				42,836
Prior	1,158,003				1,158,003
Total	1,200,839				1,200,839
Gross write-offs, 2025 - 2022					0
Gross write-offs, 2021					0
Gross write-offs, prior					1,652
Gross write-offs					1,652
Carrying Value \| Debt-to-Value Ratio, Less Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	40,832				40,832
Prior	1,096,431				1,096,431
Total	1,137,263				1,137,263
Carrying Value \| Debt-to-Value Ratio, Greater Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	2,004				2,004
Prior	61,572				61,572
Total	63,576				63,576
Carrying Value \| Non-QM loans
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	36,906				36,906
Prior	620,854				620,854
Total	657,760				657,760	722,392
Gross write-offs, 2025 - 2022					0
Gross write-offs, 2021					0
Gross write-offs, prior					0
Gross write-offs					0
Carrying Value \| Non-QM loans \| Debt-to-Value Ratio, Less Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	35,000				35,000
Prior	612,654				612,654
Total	647,654				647,654
Carrying Value \| Non-QM loans \| Debt-to-Value Ratio, Greater Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	1,906				1,906
Prior	8,200				8,200
Total	10,106				10,106
Carrying Value \| Business purpose loans
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	5,930				5,930
Prior	100,879				100,879
Total	106,809				106,809	130,633
Gross write-offs, 2025 - 2022					0
Gross write-offs, 2021					0
Gross write-offs, prior					1,458
Gross write-offs					1,458
Carrying Value \| Business purpose loans \| Debt-to-Value Ratio, Less Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	5,832				5,832
Prior	96,098				96,098
Total	101,930				101,930
Carrying Value \| Business purpose loans \| Debt-to-Value Ratio, Greater Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	98				98
Prior	4,781				4,781
Total	4,879				4,879
Carrying Value \| Legacy RPL/NPL loans
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	0				0
Prior	436,270				436,270
Total	436,270				436,270	$ 457,654
Gross write-offs, 2025 - 2022					0
Gross write-offs, 2021					0
Gross write-offs, prior					194
Gross write-offs					194
Carrying Value \| Legacy RPL/NPL loans \| Debt-to-Value Ratio, Less Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	0				0
Prior	387,679				387,679
Total	387,679				387,679
Carrying Value \| Legacy RPL/NPL loans \| Debt-to-Value Ratio, Greater Than 80 Percent
Financing Receivable, Credit Quality Indicator [Line Items]
2025 - 2022	0				0
2021	0				0
Prior	48,591				48,591
Total	$ 48,591				$ 48,591