Long-term investments - Maximum Exposure (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Schedule of Investments [Line Items]
Equity method investment in Cespira	$ 44,028	$ 42,714
Cespira
Schedule of Investments [Line Items]
Accounts receivable due from Cespira	$ 289	$ 274

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