Variable interest entities - Schedule of Unfunded Commitments VIEs (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Variable Interest Entity [Line Items]
Maximum loss exposure	$ 3,143	$ 0
Assets
Variable Interest Entity [Line Items]
Maximum loss exposure	3,143	0
Liabilities
Variable Interest Entity [Line Items]
Maximum loss exposure	0	0
Unfunded commitments
Variable Interest Entity [Line Items]
Maximum loss exposure	$ 0	$ 0