Allowance for expected credit losses - Narrative (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
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Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
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| Financing Receivable, Allowance for Credit Loss [Line Items] | |||||
| Allowance for expected credit losses | $ 27.7 | $ 27.7 | $ 27.6 | ||
| Current expected credit losses (gains) | $ (0.9) | $ (3.4) | $ 0.1 | $ (3.4) | |
| Credit Rating Agencies | Assets within scope of credit losses | Credit concentration risk | |||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | |||||
| Concentration risk, percentage | 65.00% | ||||
| Credit Rating Agencies | Assets within scope of credit losses | Credit concentration risk | A- Or Better Rating | |||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | |||||
| Concentration risk, percentage | 97.00% | ||||
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- Definition Assets Within Scope Of Credit Losses, Allowance For Credit Loss No definition available.
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of credit loss expense (reversal of expense) for financing receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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