Related party transactions - Schedule of investments in debt and equity of affiliates (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Related Party Transaction [Line Items]
Equity in earnings/(loss) from affiliates	$ 2,821	$ 3,141
ARC Home
Related Party Transaction [Line Items]
Loan securitization, ownership interest	66.00%
Arc Home
Related Party Transaction [Line Items]
Equity in earnings/(loss) from affiliates	$ 4,125	1,141
Residential investments - Fair value / Net income /(loss)
Related Party Transaction [Line Items]
Equity in earnings/(loss) from affiliates	(1,304)	2,000
Non-QM Loans
Related Party Transaction [Line Items]
Equity in earnings/(loss) from affiliates	(1,167)	1,289
Re/Non-Performing Securities
Related Party Transaction [Line Items]
Equity in earnings/(loss) from affiliates	$ (137)	$ 711
Related Party \| ARC Home
Related Party Transaction [Line Items]
Loan securitization, ownership interest	66.00%	44.60%
Assets \| Related Party
Related Party Transaction [Line Items]
Investments, assets	$ 61,345	$ 47,454
Cash and Other assets/(liabilities)	1,291	910
Assets \| Related Party \| Arc Home
Related Party Transaction [Line Items]
Investments, assets	50,016	30,778
Assets \| Related Party \| Residential investments - Fair value / Net income /(loss)
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	10,038	15,766
Assets \| Related Party \| Non-QM Loans
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	9,439	13,304
Assets \| Related Party \| Re/Non-Performing Securities
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	599	2,462
Liabilities \| Related Party
Related Party Transaction [Line Items]
Investments, liabilities	(12)	(613)
Cash and Other assets/(liabilities)	(12)	(25)
Liabilities \| Related Party \| Arc Home
Related Party Transaction [Line Items]
Investments, liabilities	0	0
Liabilities \| Related Party \| Residential investments - Fair value / Net income /(loss)
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	0	(588)
Liabilities \| Related Party \| Non-QM Loans
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	0	0
Liabilities \| Related Party \| Re/Non-Performing Securities
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	0	(588)
Equity \| Related Party
Related Party Transaction [Line Items]
Investments, equity	61,333	46,841
Cash and Other assets/(liabilities)	1,279	885
Equity \| Related Party \| Arc Home
Related Party Transaction [Line Items]
Investments, equity	50,016	30,778
Equity \| Related Party \| Residential investments - Fair value / Net income /(loss)
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	10,038	15,178
Equity \| Related Party \| Non-QM Loans
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	9,439	13,304
Equity \| Related Party \| Re/Non-Performing Securities
Related Party Transaction [Line Items]
Real Estate Securities, Excess MSRs and Loans, at fair value	$ 599	$ 1,874

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