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Derivative financial instruments - Narrative (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024 | May 31, 2024 | Mar. 31, 2021
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Treasury rate lock | 2021 Senior Notes |  |  |  |
Derivative [Line Items] |  |  |  |
Treasury lock on fair value edges, amount |  |  |  | $ 350,000
Derivative instrument, gain (loss) amortized | $ 85 | $ 206 |  |
Treasury rate lock | 2024 Senior Notes |  |  |  |
Derivative [Line Items] |  |  |  |
Treasury lock on fair value edges, amount |  |  | $ 400,000 |
Derivative instrument, gain (loss) amortized | $ 292 | $ 351 |  |
Maximum | Interest rate swaps |  |  |  |
Derivative [Line Items] |  |  |  |
Derivatives, maturity period | 51 months |  |  |
Maximum | Forward foreign exchange contracts |  |  |  |
Derivative [Line Items] |  |  |  |
Derivatives, maturity period | 51 months |  |  |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 20 -Name Accounting Standards Codification -Section 25 -Paragraph 6A -Publisher FASB -URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480237/815-40-50-5 + Details
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- Definition Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Net fair value of all derivative instruments designated as fair value hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B + Details
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