Interest-bearing loans and borrowings - Narrative (Details) - Convertible debt - Convertible senior notes $ / shares in Units, $ in Thousands		3 Months Ended
Feb. 02, 2024 USD ($) shares $ / shares	Mar. 31, 2026 USD ($) d	Dec. 31, 2025 USD ($)
Debt Instrument [Line Items]
Principal Amount	$ 402,500	$ 402,500	$ 402,500
Option to purchase additional notes	52,500
Net proceeds from the offering	389,100
Lender fees and issuance costs	$ 13,400
Interest rate on notes	2.50%	3.06%
Conversion ratio	10.5601
Conversion price (in USD per share) \| $ / shares	$ 94.70
Convertible number of equity instruments (in shares) \| shares	5,950,600
Threshold percentage of stock price trigger		130.00%
Threshold trading days \| d		20
Threshold consecutive trading days \| d		30
Percentage of redemption price principal amount		100.00%

Amount of option to purchase maximum additional debt instrument at time of issuance.

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The Percentage of redemption price equal principal amount of the notes to be redeemed.

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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