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Basis of Presentation and Significant Accounting Policies (Details) - USD ($) $ in Millions | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021 | May 18, 2018 | Jul. 31, 2012
Ark |  |  |  |
Basis of Presentation |  |  |  |
Percent of shares outstanding | 12.50% |  |  |
Fresh Insurance Services Group Limited |  |  |  |
Basis of Presentation |  |  |  |
Ownership interest (as a percent) |  |  | 100.00% |
NSM Insurance HoldCo, LLC |  |  |  |
Basis of Presentation |  |  |  |
Ownership interest (as a percent) | 96.50% | 96.50% |  |
Fully diluted ownership interest (as a percent) | 87.30% | 87.30% |  |
Asset Management (Kudu) |  |  |  |
Basis of Presentation |  |  |  |
Ownership interest (as a percent) | 99.10% | 99.30% |  |
Fully diluted ownership interest (as a percent) | 84.50% | 84.70% |  |
HG Global |  |  |  |
Basis of Presentation |  |  |  |
Percentage of par value of policy reinsured | 15.00% |  |  |
Surplus notes | $ 503.0 |  |  | $ 503.0
HG Global | Preferred Stock |  |  |  |
Basis of Presentation |  |  |  |
Ownership interest (as a percent) | 96.90% | 96.90% |  |
HG Global | Common equity securities |  |  |  |
Basis of Presentation |  |  |  |
Ownership interest (as a percent) | 88.40% | 88.40% |  |
Ark |  |  |  |
Basis of Presentation |  |  |  |
Ownership interest (as a percent) | 72.00% |  |  |
Ark | Ark |  |  |  |
Basis of Presentation |  |  |  |
Ownership interest (as a percent) | 72.00% | 72.00% |  |
Fully diluted ownership interest (as a percent) | 63.00% | 63.00% |  |
Ark | Ark |  |  |  |
Basis of Presentation |  |  |  |
Fully diluted ownership interest (as a percent) | 63.00% |  |  |

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