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Held for Sale and Discontinued Operations - (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Discontinued Operations [Line Items} |  |  |  |  |
Net gain from sale of discontinued operations, net of tax | $ (1.0) | $ 0.0 | $ (0.1) | $ 0.7 |
Connecticut | Discontinued Operations, Held-for-sale |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |
Assets held for sale | 3.0 |  | 3.0 |  | $ 3.0
Sirius Group | Swedish Tax Authority | Sirius Group |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |
Contingent liability | 16.5 |  | $ 16.5 |  | $ 16.5
Change in contingent liability | $ (1.0) |  |  |  |

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