Segment financial information - Summary of Net Assets Classified As Held for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Segment financial information
Assets held for sale-current	$ 55,878	$ 0
Liabilities held for sale-current	59,075	$ 0
Disposal Group, Held-for-Sale, Not Discontinued Operations \| Mahipapa
Segment financial information
Property, plant and equipment, net of accumulated depreciation	46,051
Other assets	9,827
Assets held for sale-current	55,878
Long-term debt, net	51,116
Other liabilities	7,959
Liabilities held for sale-current	$ 59,075

Disposal Group, Including Discontinued Operation, Long-Term Debt, Net, Current

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