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v3.20.2

Investment Securities - Significant Unobservable Inputs (Details) $ / shares in Units, $ in Millions | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 USD ($) $ / shares | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) $ / shares | Dec. 31, 2018 USD ($)
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 2,533.4 | $ 2,569.4 | $ 2,746.0 | $ 2,328.7
Investments in kudu participation contracts | $ 57.5 | $ 74.4 |  |
Marketing Technology (MediaAlpha) | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 180.0 |
Marketing Technology (MediaAlpha) | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate |  |  | 15.00% |
Marketing Technology (MediaAlpha) | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Revenue Growth Rate |  |  | 4.00% |
Kudu Investments | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 266.5 |
Kudu Investments | Minimum | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 18.00% |  | 15.00% |
Kudu Investments | Minimum | Terminal Multiple | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Cash Flow Exit Multiple | 6 |  | 6 |
Kudu Investments | Maximum | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 23.00% |  | 22.00% |
Kudu Investments | Maximum | Terminal Multiple | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Cash Flow Exit Multiple | 12 |  | 12 |
PassportCard/DavidShield | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 90.0 |
PassportCard/DavidShield | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate |  |  | 22.00% |
PassportCard/DavidShield | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Revenue Growth Rate |  |  | 4.00% |
Elementum Holdings, L.P. | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 55.1 |
Elementum Holdings, L.P. | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate |  |  | 20.00% |
Terminal Revenue Growth Rate |  |  | 4.00% |
Private debt instruments | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 23.7 |
Private debt instruments | Minimum | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 5.00% |  | 4.00% |
Private debt instruments | Maximum | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 10.00% |  | 9.00% |
All other | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 23.7 |
All other | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Revenue Growth Rate |  |  | 4.00% |
All other | Minimum | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 20.00% |  | 25.00% |
All other | Maximum | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 24.00% |  | 32.00% |
Noblr, Inc. | Standard Poors NR Rating | Recent transaction |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 5.0 |
Noblr, Inc. | Recent transaction | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Share price (in USD per share) | $ / shares |  |  | $ 2.17 |
Zillion Insurance Services | Standard Poors NR Rating | Recent transaction |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 2.5 |
Zillion Insurance Services | Recent transaction | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | 2.5 |
Compare.com | Standard Poors NR Rating | Estimated Net Realizable Value |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | 2.5 |
Compare.com | Estimated Net Realizable Value | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value |  |  | $ 2.5 |
Zillion Insurance Services |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Investments in kudu participation contracts | $ 2.5 |  |  |
Kudu |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Investments in kudu participation contracts | 57.4 |  |  |
Passport/DavidShield |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Investments in kudu participation contracts | 15.0 |  |  |
Level 3 | Marketing Technology (MediaAlpha) | Standard Poors NR Rating | Valuation Technique, Probability Weighted Expected Return Method [Member] |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 475.0 |  |  |
Level 3 | Marketing Technology (MediaAlpha) | Weight Ascribed to DCF [Member] | Standard Poors NR Rating | Valuation Technique, Probability Weighted Expected Return Method [Member] |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Measurement input | 0.35 |  |  |
Level 3 | Marketing Technology (MediaAlpha) | Weight Ascribed to IPO [Member] | Standard Poors NR Rating | Valuation Technique, Probability Weighted Expected Return Method [Member] |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Measurement input | 0.65 |  |  |
Level 3 | Marketing Technology (MediaAlpha) | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Measurement input | 0.13 |  |  |
Level 3 | Marketing Technology (MediaAlpha) | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Measurement input | 0.04 |  |  |
Level 3 | Marketing Technology (MediaAlpha) | Measurement Input, Revenue Multiple [Member] | Standard Poors NR Rating | Valuation Technique, Probability Weighted Expected Return Method [Member] |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Measurement input | 2.00 |  |  |
Level 3 | Kudu Investments | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 325.5 |  |  |
Level 3 | PassportCard/DavidShield | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 95.0 |  |  |
Level 3 | PassportCard/DavidShield | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 23.00% |  |  |
Level 3 | PassportCard/DavidShield | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Revenue Growth Rate | 4.00% |  |  |
Level 3 | Elementum Holdings, L.P. | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 55.1 |  |  |
Level 3 | Elementum Holdings, L.P. | Discount rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value, discount rate | 19.00% |  |  |
Level 3 | Elementum Holdings, L.P. | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Revenue Growth Rate | 4.00% |  |  |
Level 3 | Private debt instruments | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 17.9 |  |  |
Level 3 | All other | Standard Poors NR Rating | Discounted cash flow |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 18.1 |  |  |
Level 3 | All other | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Terminal Revenue Growth Rate | 4.00% |  |  |
Level 3 | Noblr, Inc. | Standard Poors NR Rating | Recent transaction |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 8.7 |  |  |
Level 3 | Noblr, Inc. | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Share price (in USD per share) | $ / shares | $ 2.17 |  |  |
Level 3 | Zillion Insurance Services | Standard Poors NR Rating | Recent transaction |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Fair value investments | $ 5.0 |  |  |
Level 3 | Zillion Insurance Services | Measurement Input, Long-term Revenue Growth Rate | Standard Poors NR Rating |  |  |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |
Assets, fair value | $ 5.0 |  |  |

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