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Investment Securities - Significant Unobservable Inputs (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Other long-term investments | $ 2,071.1 | $ 1,998.2
Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
New and existing contracts deployed | 0.2 | 163.8
Level 3 | Recent transaction |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Other long-term investments | 18.7 | 19.0
Level 3 | Discounted cash flow |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Other long-term investments | 15.4 | 15.5
Level 3 | Discounted cash flow | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | 930.6 | 890.5
Level 3 | Discounted cash flow | PassportCard/DavidShield |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | 150.0 | 150.0
Level 3 | Discounted cash flow | Elementum |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | 35.0 | 35.0
Level 3 | Discounted cash flow | Preferred Securities |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value | $ 30.1 | 28.2
Level 3 | Probability weighted expected return method | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair Value |  | $ 69.1
Level 3 | Discount Rate | Discounted cash flow | PassportCard/DavidShield |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 24.00% | 24.00%
Level 3 | Discount Rate | Discounted cash flow | Elementum |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 21.00% | 21.00%
Level 3 | Discount Rate | Discounted cash flow | Preferred Securities |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 7.00% | 8.00%
Level 3 | Discount Rate | Discounted cash flow | Minimum |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 11.00% | 11.00%
Level 3 | Discount Rate | Discounted cash flow | Minimum | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 16.00% | 18.00%
Level 3 | Discount Rate | Discounted cash flow | Maximum |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 12.00% | 12.00%
Level 3 | Discount Rate | Discounted cash flow | Maximum | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 24.00% | 25.00%
Level 3 | Terminal Cash Flow Exit Multiple | Discounted cash flow | Minimum | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 700.00% | 700.00%
Level 3 | Terminal Cash Flow Exit Multiple | Discounted cash flow | Maximum | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 2200.00% | 2200.00%
Level 3 | Terminal Revenue Growth Rate | Discounted cash flow | PassportCard/DavidShield |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 4.00% | 4.00%
Level 3 | Terminal Revenue Growth Rate | Discounted cash flow | Elementum |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 4.00% | 4.00%
Level 3 | Measurement Input, Pre-Tax Discount Rate | Discounted cash flow | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 19.00% | 20.00%
Level 3 | Measurement, Input, Pre-Tax Terminal Cash Flow Exit Multiple | Discounted cash flow | Kudu’s Participation Contracts |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Rate | 1400.00% | 1300.00%

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