Derivative financial instruments - Schedule of fair value of derivative instruments (Details) - Interest rate swaps - cash flow hedges - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Offsetting Liabilities [Line Items]
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Current assets	$ 761	$ 2,653
Non-current assets	213	548
Current liabilities	0	(14)
Non-current liabilities	(1,615)	(1,779)
Net derivative assets (liabilities)	$ (641)	$ 1,408

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Carrying amount as of the balance sheet date of the asset arising from derivative instruments and hedging activities, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Sum as of the balance sheet date of the (a) fair values of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and (b) the carrying amounts of the liabilities arising from financial instruments or contracts used to mitigate a specified risk (hedge), and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

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Fair value of liability arising from contracts that meet the criteria of being accounted for as derivative instruments, financial instrument or contract used to mitigate a specified risk (hedge), energy marketing activities (trading activities), expected to be settled after one year or beyond the normal operating cycle, if longer. Examples of energy marketing activities include, but are not limited to, trading of electricity, coal, natural gas and oil using financial instruments, including, but not limited to, forward contracts, options and swaps.

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Carrying amount as of the balance sheet date of the assets arising from derivative contracts and hedging activities, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer.

+ References

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Indicates line item in statement of financial position that includes derivative liability.

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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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