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v3.25.3

Fair Value (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2024 | Jun. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Fair Value Disclosure [Line Items] |  |  |  |  |
Transfers between Fair Value Hierarchies |  | $ 0.0 | $ 0.0 |  |
Allowance for Credit Loss |  |  | 0.1 |  | $ 0.1
Debt Securities, Available-for-Sale, Realized Gain | $ 0.1 |  | 0.1 | $ 0.5 |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Equity Securities, FV-NI, Cost |  |  | 7.9 |  |
Debt and Equity Securities, Unrealized Gain (Loss) |  |  | 0.6 |  |
Equity Securities, FV-NI |  |  | 8.5 |  |
Net Assets |  |  | 17.9 |  |
Net Assets |  |  | 17.9 |  |
U.S. Treasury debt securities |  |  |  |  |
Fair Value Disclosure [Line Items] |  |  |  |  |
Allowance for Credit Loss |  |  | 0.0 |  |
Corporate/Other debt securities |  |  |  |  |
Fair Value Disclosure [Line Items] |  |  |  |  |
Allowance for Credit Loss |  |  | $ 0.1 |  | $ 0.1

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