Deferred acquisition costs and deferred ceding commissions - Schedule of Acquisition Costs Deferred and Amortized for Insurance Business Retained by Accelerant (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] | ||||
| Beginning balance | $ 85.0 | $ 56.3 | $ 76.9 | $ 60.7 |
| Direct commissions and other acquisition costs on retained business | 55.5 | 12.8 | 97.6 | 25.5 |
| Amortization of deferred acquisition costs | (34.8) | (18.2) | (68.4) | (35.3) |
| Foreign currency translation | (0.3) | 0.3 | (0.7) | 0.3 |
| Ending balance | $ 105.4 | $ 51.2 | $ 105.4 | $ 51.2 |
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- Definition Amount of amortization expense (reversal of expense) for deferred policy acquisition costs. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of foreign currency translation gain (loss) which increases (decreases) deferred policy acquisition costs. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred policy acquisition cost capitalized on contract remaining in force. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of deferred policy acquisition cost capitalized. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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