Deferred acquisition costs - Schedule of Deferred Acquisition Costs (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	$ 6,791	$ 6,524
Capitalization	35
Capitalization		(7)
Amortization	(708)	(555)
Ending balance	$ 6,118	$ 5,962

Amount of amortization expense (reversal of expense) for deferred policy acquisition costs.

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+ Details

- Definition

Amount of deferred policy acquisition cost capitalized on contract remaining in force.

+ References + Details