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Investment Securities - Significant Unobservable Inputs (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Other long-term investments | $ 2,958.5 | $ 2,150.2
Recent transaction | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Other long-term investments | 250.4 | 23.4
Discounted cash flow | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Other long-term investments | $ 16.5 | $ 14.5
Discounted cash flow | Discount Rate | Minimum | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 11.00% | 11.00%
Discounted cash flow | Discount Rate | Maximum | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 12.00% | 12.00%
Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
New and existing contracts deployed | $ 201.7 | $ 103.5
Kudu’s Participation Contracts | Discounted cash flow | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | $ 1,285.0 | $ 1,008.4
Kudu’s Participation Contracts | Discounted cash flow | Discount Rate | Minimum | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 16.00% | 17.00%
Kudu’s Participation Contracts | Discounted cash flow | Discount Rate | Maximum | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 25.00% | 25.00%
Kudu’s Participation Contracts | Discounted cash flow | Terminal Cash Flow Exit Multiple | Minimum | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 700.00% | 700.00%
Kudu’s Participation Contracts | Discounted cash flow | Terminal Cash Flow Exit Multiple | Maximum | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 2200.00% | 2200.00%
Kudu’s Participation Contracts | Discounted cash flow | Measurement Input, Pre-Tax Discount Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 19.00% | 19.00%
Kudu’s Participation Contracts | Discounted cash flow | Measurement, Input, Pre-Tax Terminal Cash Flow Exit Multiple | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 1400.00% | 1400.00%
PassportCard/DavidShield | Discounted cash flow | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | $ 170.0 | $ 150.0
PassportCard/DavidShield | Discounted cash flow | Discount Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 24.00% | 24.00%
PassportCard/DavidShield | Discounted cash flow | Terminal Revenue Growth Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 4.00% | 4.00%
Elementum | Discounted cash flow | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | $ 35.0 | $ 35.0
Elementum | Discounted cash flow | Discount Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 22.00% | 22.00%
Elementum | Discounted cash flow | Terminal Revenue Growth Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 3.00% | 4.00%
Preferred securities | Discounted cash flow | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | $ 35.6 | $ 31.4
Preferred securities | Discounted cash flow | Discount Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 8.00% | 9.00%
Private equity securities | Discounted cash flow | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | $ 21.9 |
Private equity securities | Discounted cash flow | Discount Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 35.00% |
Private equity securities | Discounted cash flow | Terminal Revenue Growth Rate | Level 3 |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 4.00% |

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