Related party transactions - Transactions with Arc Home (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Residential mortgage loans sold by Arc Home to the Company \| Residential mortgage loans \| Arc Home \| Related Party
Related Party Transaction [Line Items]
Residential mortgage loans sold by Arc Home to the Company	$ 0	$ 0	$ 475	$ 60,957

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