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Subsequent Events (Details) - Subsequent Event - USD ($) $ / shares in Units, $ in Millions | Nov. 05, 2020 | Nov. 02, 2020
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Watford Holdings Ltd |  |
Subsequent Event [Line Items] |  |
Business acquisition, gross transaction value |  | $ 700.0
Business acquisition, share price (per share) |  | $ 35.00
Percentage ownership after merger transaction |  | 40.00%
Watford Holdings Ltd | Warburg Pincus LLC |  |
Subsequent Event [Line Items] |  |
Percentage ownership after merger transaction |  | 30.00%
Watford Holdings Ltd | Kelso And Company |  |
Subsequent Event [Line Items] |  |
Percentage ownership after merger transaction |  | 30.00%
Variable Interest Entity, Not Primary Beneficiary | Bellemeade Re 2020-3 Ltd. |  |
Subsequent Event [Line Items] |  |
Aggregate excess of loss reinsurance agreement | $ 451.8 |
Excess of loss agreement aggregate losses | $ 173.8 |
Excess of loss agreement period | ten |
SPV issuance of insurance linked notes | $ 418.2 |
Variable Interest Entity, Not Primary Beneficiary | Bellemeade Re 2020-3 Ltd. | Funded by directly provided capacity |  |
Subsequent Event [Line Items] |  |
Initial Coverage, Amount | $ 33.7 |

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