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Contingencies (Details) (USD $) In Millions, unless otherwise specified | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2007 | Mar. 31, 2013 | Mar. 31, 2012 | Mar. 31, 2013 Esurance | Dec. 31, 2011 Esurance | Dec. 31, 2012 Esurance | Dec. 30, 2011 Esurance
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Warranty agreement period |  |  |  | 18 months |  |  |
Covenant breach agreement period |  |  |  | 2 years |  |  |
Non-soliciation agreement period |  |  |  | 3 years |  |  |
Percentage of fluctuation in loss reserves of transferred subsidiaries retained |  |  |  |  |  | 90.00% |
Sales of consolidated and unconsolidated affiliates, net of cash sold |  | $ 31.3 | $ 0 |  | $ 1,010.0 |  |
Gain on sale of business in discontinued operations |  |  |  |  | 700 |  |
Disposal Group Including Discontinued Operation Book Value |  |  |  |  | 308 |  |
Total amount in dispute with Allstate |  |  |  |  |  |  | 20
DAC amount in dispute with Allstate, Pre-tax |  |  |  |  |  |  | 24.7
DAC amount in dispute with Allstate, after-tax |  |  |  |  |  |  | 16.0
Extra contractual obligation in dispute with Allstate, pre-tax |  |  |  |  |  |  | 5.2
Extra contractual obligation in dispute with Allstate, after-tax |  |  |  |  |  |  | 3.4
Proceeds from Sale, Maturity and Collection of Investments | $ 39 |  |  |  |  |  |

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- Definition The cash inflow associated with the deconsolidation of a previously consolidated subsidiary or sale of an entity that is related to it but not strictly controlled. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 16 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3179-108585 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 39 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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