Related party transactions - Investments in debt and equity affiliates (Details) - shares	Aug. 01, 2025	Sep. 30, 2025	Dec. 31, 2024
Arc Home
Related Party Transaction [Line Items]
Loan securitization, ownership interest		66.00%
Arc Home \| Related Party
Related Party Transaction [Line Items]
Loan securitization, ownership interest		66.00%	44.60%
Loan securitization, additional interest	21.40%
Share issued in connection with acquisition (in shares)	2,027,676
MATH \| Related Party
Related Party Transaction [Line Items]
Loan securitization, ownership interest		47.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

AG Mortgage Investment Trust, Inc. 10-Q