Quantitative and qualitative disclosure about market risk - Geographical area (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets
Total	$ 17,096	$ 10,073	$ 3,569
Hong Kong
Revenues from External Customers and Long-Lived Assets
Total	16,783	10,047	3,442
Australia
Revenues from External Customers and Long-Lived Assets
Total	115		$ 127
PRC
Revenues from External Customers and Long-Lived Assets
Total	$ 198	$ 26

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details