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Acquisition of Businesses - Narrative (Details) - Crop Risk Services - USD ($) $ in Millions | Jul. 03, 2023 | Mar. 31, 2024
--- | --- | ---
Business Acquisition [Line Items] |  |
Payments to acquire subsidiaries | $ 234 |
Net tangible assets acquired, at fair value | 24 |
Acquisition expenses incurred | 3 |
Goodwill recorded | 85 |
Amount of goodwill expected to be tax deductible | 79 |
Customer relationships |  |
Business Acquisition [Line Items] |  |
Intangible assets acquired | 124 |
Finite-lived intangible assets useful life |  | 14 years
Crop year 2022 |  |
Business Acquisition [Line Items] |  |
Gross written premiums | $ 1,200 |

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