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Variable Interest Entities (Details) (USD $) In Millions, unless otherwise specified | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  | 12 Months Ended |  |  | 12 Months Ended | 1 Months Ended | 12 Months Ended |  | 12 Months Ended |  |  | 12 Months Ended |
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Dec. 31, 2011 company | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2012 | Sep. 30, 2012 | Jun. 30, 2012 | Mar. 31, 2012 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2013 HG Global | Dec. 31, 2012 HG Global | Dec. 31, 2013 Prospector Turtle Fund [Member] | Dec. 31, 2013 Prospector | Dec. 31, 2012 Prospector | Dec. 31, 2011 Prospector | Dec. 31, 2013 Houston General Insurance [Member] | Dec. 31, 2004 Houston General Insurance [Member] | Dec. 31, 2012 Houston General Insurance [Member] | Dec. 31, 2005 Houston General Insurance [Member] | Dec. 31, 2013 Prospector Offshore Fund Ltd [Member] | Dec. 31, 2011 Tuckerman Fund I | Dec. 31, 2012 Entities Owned by Tuckerman Fund I company | Dec. 31, 2012 Common Stock BAM | Dec. 31, 2011 Common Stock Tuckerman Fund I | Dec. 31, 2011 Common Stock Tuckerman Fund I | Dec. 31, 2005 Houston General Insurance Company | Dec. 31, 2012 BAM | Dec. 31, 2013 BAM | Dec. 31, 2013 HG Global | Dec. 31, 2012 HG Global | Dec. 31, 2013 Surplus Note Houston General Insurance [Member] | Dec. 31, 2013 First Loss Reinsurance Treaty [Member] HG Global | Dec. 31, 2013 First Loss Reinsurance Treaty [Member] BAM | Dec. 31, 2013 First Loss Reinsurance Treaty [Member] HG Global trust | Dec. 31, 2013 Amendment [Member] Houston General Insurance [Member]
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 503.0 |  |  |  |  |  |  |  |  |  |  |  |
Percentage of par value of policy reinsured |  |  |  |  |  | 15.00% |  |  |  |  | 15.00% |  | 15.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.00% |  |  | 15.00% |  |  |
Percentage of Premiums |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 60.00% |  |
Number of Trust |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |
Right to elect directors on board number |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |
Proceeds from Contributions from Parent |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets related to consolidated VIE's |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 249.2 | 238.6 |  | 2.6 |  | 22.6 |  |  | 17.6 |  |  |  |  | 149.4 |  |  |  |  |  |  |  |  |
Total liabilities related to consolidated VIE's |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 90.6 | 94.4 |  | 4.2 |  | 43.8 |  |  | 9.9 |  |  |  |  | 127.6 |  |  |  |  |  |  |  |  |
Surplus notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.0 |  |  | 23.7 |  |  |  |  |  |  |  |  |  | 503.0 | 503.0 |  |  |  |  | 4.0
Interest Paid |  |  |  |  |  |  |  |  |  | 42.6 | 44.6 | 59.0 |  |  |  |  |  |  | 19.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of debt, principal |  |  |  |  |  |  |  |  |  | 275.0 | 75.0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.0 |  |  |  |
Accumulated losses |  | 2,802.3 |  |  |  | 2,542.7 |  |  |  | 2,802.3 | 2,542.7 |  |  |  |  |  |  |  | 1.6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accrued interest on surplus notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Noncontrolling interest in VIE |  | 491.9 |  |  |  | 526.4 |  |  |  | 491.9 | 526.4 |  | 16.6 | 16.6 |  | 46.2 | 41.5 |  |  |  |  |  |  | 3.5 |  |  |  |  |  | (36.0) | (97.6) | 16.6 | 16.6 |  |  |  |  |
Net Income (Loss) Attributable to Parent |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 14.5 | 9.3 | (1.0) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-controlling interest in consolidated subsidiaries |  | 0.3 | (1.1) | (11.1) | (0.5) | (12.0) | (30.9) | 12.1 | 16.8 | (12.4) | (14.0) | 41.5 |  |  |  | 4.0 | 2.7 | (0.2) |  |  |  |  |  | 2.2 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest in VIE (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 68.90% |  |  |  |  |  |  |  | 71.70% |  |  |  | 94.00% | 94.00% |  |  |  |  |  |  |  |  |  |
Number of small manufacturing companies owned by the Tuckerman Fund I from whom the entity received shares | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |
Captial at risk, investment in the fund |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 112.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.31) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 27 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 7 + Details
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- Definition Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=28200181&loc=SL6759159-111685 + Details
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- Definition Accrued interest on surplus notes issued by VIE. The interest is eliminated in consolidation with the primary beneficiary. + References No definition available. + Details
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- Definition Represents the number of manufacturing companies from whom the entity received the shares. + References No definition available. + Details
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- Definition Percentage of par value of policy reinsured. + References No definition available. + Details
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