Long-term investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Schedule of Investments [Line Items]
Long-term investments	$ 43,135	$ 42,714
Cespira Canada LP
Schedule of Investments [Line Items]
Long-term investments	19,871	19,385
Cespira Sweden AB
Schedule of Investments [Line Items]
Long-term investments	$ 23,264	$ 23,329

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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