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Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified |  |  |  |  | 1 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Dec. 31, 2008 | Oct. 31, 2011 Esurance | Dec. 31, 2011 AutoOne | Dec. 31, 2011 Discontinued Operations. | Dec. 31, 2010 Discontinued Operations. | Dec. 31, 2011 Sirius group | Dec. 31, 2010 Sirius group
Discontinued Operations |  |  |  |  |  |  |  |  |  |
Gain (loss) on sale of discontinued operation, pre-tax |  |  |  |  |  | $ 29.6 |  |  |  |
Gain (loss) on sale of discontinued operation, net of tax |  |  |  |  | 677.5 | 19.2 |  |  |  |
Assets held for sale |  |  |  |  |  |  |  |  |  |
Fixed maturity investments, at fair value | 6,221.9 | 5,786.1 |  |  |  |  | 111.8 | 593.8 |  |
Short-term investments, at amortized cost (which approximates fair value) | 846.0 | 975.3 |  |  |  |  |  | 131.0 |  |
Common equity securities, at fair value | 755.0 | 667.0 |  |  |  |  |  | 43.0 |  |
Convertible fixed maturity investments, at fair value | 143.8 | 143.0 |  |  |  |  |  | 17.2 |  |
Other long-term investments | 301.3 | 372.1 |  |  |  |  |  | 4.0 |  |
Total investments | 8,268.0 | 7,943.5 |  |  |  |  | 111.8 | 789.0 | 3,640.5 | 4,116.2
Cash | 705.4 | 395.0 |  |  |  |  | 5.5 | 39.8 |  |
Reinsurance recoverable on paid and unpaid losses | 2,537.8 | 2,407.1 |  |  |  |  |  | 34.4 | 353.7 | 469.4
Insurance premiums receivable | 489.2 | 532.5 |  |  |  |  | 8.8 | 102.9 |  |
Deferred acquisition costs | 187.0 | 176.1 |  |  |  |  | 2.2 | 34.7 |  |
Deferred tax asset | 630.6 | 535.9 |  |  |  |  | 1.9 | 67.8 |  |
Other assets | 681.9 | 730.0 |  |  |  |  | 2.4 | 54.2 |  |
Total assets | 14,064.0 | 14,534.1 |  |  |  |  | 132.6 | 1,122.8 | 5,337.9 | 5,618.7
Liabilities held for sale |  |  |  |  |  |  |  |  |  |
Loss and loss adjustment expense reserves | 5,702.3 | 5,736.8 | 6,379.2 | 7,029.4 |  |  | 64.7 | 450.4 | 2,343.7 | 2,441.3
Unearned insurance premiums | 846.9 | 938.7 |  |  |  |  | 34.1 | 201.6 |  |
Accrued incentive compensation | 187.9 | 157.4 |  |  |  |  |  | 19.1 |  |
Other liabilities | 534.1 | 557.5 |  |  |  |  | 8.8 | 80.4 |  |
Total liabilities | 9,396.1 | 10,273.3 |  |  |  |  | 107.6 | 751.5 | 3,784.1 | 3,863.0
Net assets held for sale |  |  |  |  |  | $ 25.0 | $ 25.0 | $ 371.3 |  |

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