Segment reporting and concentrations - Revenues by geographic region (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment reporting and concentrations
Revenues	$ 92,142	$ 58,393	$ 182,238	$ 116,737
United States
Segment reporting and concentrations
Revenues	79,860	48,563	159,079	97,460
Canada
Segment reporting and concentrations
Revenues	3,326	2,955	6,384	5,678
United Kingdom
Segment reporting and concentrations
Revenues	2,950	2,470	5,729	4,897
The Netherlands
Segment reporting and concentrations
Revenues	2,201	2,277	4,643	4,442
Others - principally other European countries
Segment reporting and concentrations
Revenues	$ 3,805	$ 2,128	$ 6,403	$ 4,260

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

- Definition

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