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v3.7.0.1

Significant Transactions (Details) $ / shares in Units, $ in Millions |  |  |  |  |  |  | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
May 02, 2017 $ / shares | Oct. 05, 2016 USD ($) | Aug. 04, 2016 USD ($) | Jul. 21, 2016 USD ($) | Apr. 18, 2016 USD ($) | Feb. 01, 2016 USD ($) $ / shares | Dec. 31, 2017 USD ($) | Sep. 30, 2017 USD ($) | Jun. 30, 2017 USD ($) | Mar. 31, 2017 USD ($) | Sep. 30, 2016 USD ($) | Jun. 30, 2016 USD ($) | Sep. 30, 2015 $ / shares | Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($) | Dec. 31, 2016 USD ($) | Mar. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |  |  | $ 6,786.2 |  |  |  |  | $ 6,786.2 |  | $ 6,544.7 |  |
Goodwill |  |  |  |  |  |  |  |  | 31.7 | $ 31.7 |  | $ 24.1 |  | 31.7 | $ 24.1 | 31.7 | $ 24.1 | $ 24.1
Liabilities |  |  |  |  |  |  |  |  | 3,022.1 |  |  |  |  | 3,022.1 |  | 2,807.5 |  |
Sales of unconsolidated affiliates and consolidated subsidiaries, net of cash sold |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.0 | 2,248.5 |  |  |
Repayments of debt |  |  |  |  |  |  |  |  |  |  |  |  |  | 13.3 | 150.5 |  |  |
Net (loss) gain on sale of discontinued operations, net of tax |  |  |  |  |  |  |  |  | (0.6) |  |  | $ 366.6 |  | (1.6) | 366.6 |  |  |
Payments to acquire other investments |  |  |  |  |  |  |  |  |  |  |  |  |  | 55.1 | 12.9 |  |  |
Sales of common equity securities |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 183.9 | $ 676.9 |  |  |
Buzzmove |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  | 70.90% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets |  |  | $ 11.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Goodwill |  |  | 7.6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Intangible assets, net (excluding goodwill) |  |  | 1.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Liabilities |  |  | 0.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
United Kingdom, Pounds | Buzzmove |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to acquire interest in subsidiaries and affiliates |  |  | 6.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
United States of America, Dollars | Buzzmove |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to acquire interest in subsidiaries and affiliates |  |  | $ 8.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Intact Financial Corporation | OneBeacon |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of stock, price per share | $ / shares | $ 18.10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transaction book value multiple | 1.65 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tranzact |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales of unconsolidated affiliates and consolidated subsidiaries, net of cash sold |  | $ 1.2 |  | $ 221.3 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of debt |  |  |  | 56.3 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net (loss) gain on sale of discontinued operations, net of tax |  | 51.9 |  |  |  |  |  |  |  | $ (1.0) |  |  |  |  |  | 51.9 |  |
Discontinued operation, tax effect of discontinued operation |  | 30.2 |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.2 |  |
Increase of book value |  | $ 82.1 |  | $ 82.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sirius Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales of unconsolidated affiliates and consolidated subsidiaries, net of cash sold |  |  |  |  | $ 2,600.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Net (loss) gain on sale of discontinued operations, net of tax |  |  |  |  |  |  |  |  | $ (0.6) |  | $ 4.0 |  |  |  |  | 363.2 |  |
Payments to acquire other investments |  |  |  |  | $ 161.8 |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of Sirius Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recognition of foreign currency translation and other accumulated comprehensive items from the sale of Sirius Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 113.3 |  |
Symetra |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales of common equity securities |  |  |  |  |  | $ 658.0 |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, amount per share | $ / shares |  |  |  |  |  | $ 32.00 |  |  |  |  |  |  |  |  |  |  |  |
Symetra |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales of common equity securities |  |  |  |  |  | $ 658.0 |  |  |  |  |  |  |  |  |  |  |  |
Common stock, dividends, per share, cash paid | $ / shares |  |  |  |  |  | $ 0.50 |  |  |  |  |  |  | $ 0.50 |  |  |  |  |
OneBeacon |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  |  |  | 75.70% |  |  |  |  | 75.70% |  |  |  |
Business acquisition, percentage of voting interests acquired |  |  |  |  |  |  |  |  | 96.90% |  |  |  |  | 96.90% |  |  |  |
Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from acquisition |  |  |  |  |  |  | $ 1,300.0 | $ 1,300.0 |  |  |  |  |  |  |  |  |  |

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