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v3.4.0.3

Significant Transactions (Details) $ / shares in Units, ₪ in Millions, $ in Millions |  |  | 1 Months Ended | 2 Months Ended | 3 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 01, 2016 USD ($) | Nov. 06, 2015 USD ($) | Sep. 30, 2015 USD ($) | Jan. 31, 2014 USD ($) | Oct. 31, 2011 USD ($) | Feb. 23, 2015 ILS (₪) | Feb. 23, 2015 USD ($) | Feb. 19, 2014 ILS (₪) | Feb. 19, 2014 USD ($) | Jun. 30, 2016 USD ($) | Mar. 31, 2016 USD ($) $ / shares | Mar. 31, 2016 USD ($) $ / shares | Jun. 30, 2015 ILS (₪) | Jun. 30, 2015 USD ($) | Mar. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Mar. 31, 2014 USD ($) | Dec. 31, 2015 USD ($) | Sep. 01, 2015 USD ($) | Oct. 10, 2014 USD ($) | Mar. 14, 2014 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Other Investments |  |  |  |  |  |  |  |  |  |  | $ (10.9) |  |  |  | $ (6.5) |  |  |  |  |  |
Investments |  |  |  |  |  |  |  |  |  |  | 3,639.7 | $ 3,639.7 |  |  |  |  |  | $ 4,280.7 |  |  |
Sales of common equity securities |  |  |  |  |  |  |  |  |  |  | 767.5 |  |  |  | 59.9 |  |  |  |  |  |
Loss and loss adjustment expenses |  |  |  |  |  |  |  |  |  |  | 161.1 |  |  |  | 167.9 |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  |  |  |  |  |  |  |  | 8.1 |  |  |  | 2.4 |  |  |  |  |  |
Payment of contingent consideration |  |  |  |  |  |  |  |  |  |  | (7.8) |  |  |  | 0.0 |  |  |  |  |  |
Assets |  |  |  |  |  |  |  |  |  |  | 10,391.8 | 10,391.8 |  |  |  |  |  | 10,282.6 |  |  |
Goodwill |  |  |  |  |  |  |  |  |  |  | 187.9 | 187.9 |  |  | 169.2 | $ 168.9 |  | 187.9 |  |  |
Intangible Assets, Net (Excluding Goodwill) |  |  |  |  |  |  |  |  |  |  | 183.6 | 183.6 |  |  | 178.2 | 182.3 |  | 187.8 |  |  |
Goodwill and intangible assets |  |  |  |  |  |  |  |  |  |  | 371.5 | 371.5 |  |  |  |  |  | 375.7 |  |  |
Liabilities |  |  |  |  |  |  |  |  |  |  | 6,154.5 | 6,154.5 |  |  |  |  |  | 5,914.6 |  |  |
Net Income (Loss) Attributable to Noncontrolling Interest |  |  |  |  |  |  |  |  |  |  | (6.3) |  |  |  | 7.3 |  |  |  |  |  |
Cancerinsurance.com [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Interest in Subsidiaries and Affiliates |  | $ 3.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash |  | 1.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Contingent Consideration, Liability |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.8 |  |  |
Liabilities |  | $ 2.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tranzact [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Interest in Subsidiaries and Affiliates |  |  |  |  | $ 177.7 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Enterprise Value of Subsidiary |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 281.2 |
Proceeds from Contributions from Affiliates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 44.2 |  |  |  |  |
Business Combination, Contingent Consideration, Liability |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7.4 |
Ownership interest (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 63.20% |
Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 332.8 |
Tangible Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 41.4 |
Goodwill |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 145.1 |
Intangible Assets, Net (Excluding Goodwill) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 146.3 |
Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 108.7 |
TruBridge [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Interest in Subsidiaries and Affiliates |  |  | $ 31.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% |  |
Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 54.5 |  |
Goodwill |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18.7 |  |
Intangible Assets, Net (Excluding Goodwill) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 28.1 |  |
Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4.3 |  |
Star & Shield Insurance Exchange |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase of Surplus Notes |  |  |  |  |  |  |  |  |  |  | 21.0 | 21.0 |  |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |  |  |  |  | 13.3 | 13.3 |  |  |  |  |  | 14.2 |  |  |
Liabilities |  |  |  |  |  |  |  |  |  |  | 29.4 | 29.4 |  |  |  |  |  | 30.3 |  |  |
MediaAlpha [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 28.1 |  |  |  |
Percentage of gross profit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 62.50%
Payment of contingent consideration |  |  |  |  |  |  |  |  |  |  | $ 7.8 |  |  |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 70.1
Goodwill |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18.3
Goodwill and intangible assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 38.5
Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10.0
WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of Business in the Insurance Market |  |  |  |  |  |  |  |  |  |  | 85.00% |  |  |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  |  |  |  | $ 5.5 |  |  |  |  |  |  |  |  |  |  |  |
Liabilities |  |  |  |  |  |  |  |  | $ 0.7 |  |  |  |  |  |  |  |  |  |  |  |
Star & Shield LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  | $ 1.8 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lowfares.com [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  |  |  |  |  |  |  |  |  | $ 3.9 |  |  |  |  |  |  |  |  |
OneBeacon [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of Quota Share Reinsurance Agreement |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  |  |  |  |
Common Class A | MediaAlpha [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 60.00%
Common Stock | WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  |  |  | 54.00% |  | 96.10% | 96.10% |  |  |  |  |  |  |  |  |
Non-controlling interest | Star & Shield Insurance Exchange |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Income (Loss) Attributable to Noncontrolling Interest |  |  |  |  |  |  |  |  |  |  | $ (0.1) |  |  |  | (1.1) |  |  |  |  |  |
Israel, New Shekels | Common Stock | WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Additional Interest in Subsidiaries | ₪ |  |  |  |  |  |  |  |  |  |  |  |  | ₪ 91.4 |  |  |  |  |  |  |  |
Israel, New Shekels | Preferred Stock [Member] | WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates | ₪ |  |  |  |  |  |  |  | ₪ 31.5 |  |  |  |  |  |  |  |  |  |  |  |  |
Israel, New Shekels | Common Stock | Cashboard [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates | ₪ |  |  |  |  |  | ₪ 35.9 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Israel, New Shekels | Common Stock | WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates | ₪ |  |  |  |  |  |  |  | ₪ 14.4 |  |  |  |  |  |  |  |  |  |  |  |  |
United States of America, Dollars | Common Stock | WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Additional Interest in Subsidiaries |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 23.8 |  |  |  |  |  |  |
United States of America, Dollars | Preferred Stock [Member] | WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  |  |  |  |  |  | $ 9.0 |  |  |  |  |  |  |  |  |  |  |  |
United States of America, Dollars | Common Stock | Cashboard [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  |  |  |  | $ 8.9 |  |  |  |  |  |  |  |  |  |  |  |  |  |
United States of America, Dollars | Common Stock | WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  |  |  |  |  |  | 4.1 |  |  |  |  |  |  |  |  |  |  |  |
Lowfares.com [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses and Interest in Affiliates |  |  |  |  |  |  |  |  | 3.9 |  |  |  |  |  |  |  |  |  |  |  |
Cashboard [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  | 5.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  |  | 0.3 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Intangible Assets, Net (Excluding Goodwill) |  |  |  |  |  |  | 2.8 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Liabilities |  |  |  |  |  |  | $ 1.2 |  |  |  |  |  |  |  |  |  |  |  |  |  |
WOBI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |  |  | 13.4 |  |  |  |  |  |  |  |  |  |  |  |
Intangible Assets, Net (Excluding Goodwill) |  |  |  |  |  |  |  |  | $ 2.9 |  |  |  |  |  |  |  |  |  |  |  |
Sirius Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Divestiture of Interest in Subsidiaries and Affiliates |  |  |  |  |  |  |  |  |  | $ 2,600.0 |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Other Investments |  |  |  |  |  |  |  |  |  | 161.8 |  |  |  |  |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |  |  |  |  | $ 161.8 | $ 161.8 |  |  |  |  |  | 686.2 |  |  |
Essentia [Member] | OneBeacon [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) from Adjustments to Prior Period Extraordinary Items |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3.7 |  |  |  |  |  |
Crop insurance [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds related from termination of agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.0 |  |  |
Percentage of Quota Share Reinsurance Agreement |  |  |  |  |  |  |  |  |  |  | 100.00% |  |  |  |  |  |  |  |  |  |
Symetra |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales of common equity securities | $ 658.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expected [Member] | Symetra |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends Payable, Amount Per Share | $ / shares |  |  |  |  |  |  |  |  |  |  | $ 32.00 | $ 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 |  |  |  |  |  |  |  |  |  |
Symetra | Sirius Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 528.6 |  |  |
UNITED STATES |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Industry Loss Warranty Limit on Contract |  |  |  |  |  |  |  |  |  |  | 45.0 |  |  |  |  |  |  |  |  |  |
Industry Loss Trigger on Industry Loss Warranty |  |  |  |  |  |  |  |  |  |  | 15,000.0 |  |  |  |  |  |  |  |  |  |
JAPAN |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Industry Loss Warranty Limit on Contract |  |  |  |  |  |  |  |  |  |  | 25.0 |  |  |  |  |  |  |  |  |  |
Industry Loss Trigger on Industry Loss Warranty |  |  |  |  |  |  |  |  |  |  | 12,500.0 |  |  |  |  |  |  |  |  |  |
Combination One [Member] | UNITED STATES |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Industry Loss Warranty Limit on Contract |  |  |  |  |  |  |  |  |  |  | 75.0 |  |  |  |  |  |  |  |  |  |
Industry Loss Trigger on Industry Loss Warranty |  |  |  |  |  |  |  |  |  |  | 40,000.0 |  |  |  |  |  |  |  |  |  |
Combination Two [Member] | UNITED STATES |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Industry Loss Warranty Limit on Contract |  |  |  |  |  |  |  |  |  |  | 22.5 |  |  |  |  |  |  |  |  |  |
Industry Loss Trigger on Industry Loss Warranty |  |  |  |  |  |  |  |  |  |  | $ 50,000.0 |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Divestiture of Interest in Subsidiaries and Affiliates |  |  |  |  |  |  |  |  |  | 2,600.0 |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Other Investments |  |  |  |  |  |  |  |  |  | 161.8 |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Sirius Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Divestiture of Interest in Subsidiaries and Affiliates |  |  |  |  |  |  |  |  |  | 2,592.0 |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Other Investments |  |  |  |  |  |  |  |  |  | $ 161.8 |  |  |  |  |  |  |  |  |  |  |

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