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Municipal Bond Guarantee (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended | 12 Months Ended | 1 Months Ended | 3 Months Ended | 9 Months Ended |  | 3 Months Ended | 9 Months Ended |  | 1 Months Ended | 9 Months Ended |  | 9 Months Ended
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Sep. 30, 2014 BAM Contract | Sep. 30, 2014 BAM Y Contract | Dec. 31, 2013 BAM Contract | Jul. 31, 2012 HG Global | Sep. 30, 2014 HG Global | Sep. 30, 2013 HG Global | Sep. 30, 2014 HG Global | Sep. 30, 2013 HG Global | Sep. 30, 2014 HG Global Preferred Stock | Sep. 30, 2014 HG Global Common Stock | Sep. 30, 2014 Build America Mutual | Sep. 30, 2013 Build America Mutual | Sep. 30, 2014 Build America Mutual | Sep. 30, 2013 Build America Mutual | Sep. 30, 2014 HG Re | Jul. 31, 2012 BAM Management | Sep. 30, 2014 Surplus Note BAM | Sep. 30, 2014 Fixed interest rate Surplus Note BAM | Sep. 30, 2014 Variable Rate Surplus Note BAM | Sep. 30, 2014 Combination One Surplus Note BAM Y | Sep. 30, 2014 Combination Two Surplus Note BAM Y | Sep. 30, 2014 Financial Guarantee [Member]
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
basis points |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |  |  |  |
Municipal bond contract | 1,431 | 1,431 | 701 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Insured Financial Obligations, Remaining Weighted Average Contract Period |  | 12 years 11 months 0 days | 13 years 9 months 21 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Municipal bond outstanding principal | $ 9,963.6 | $ 9,963.6 | $ 4,703.7 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Municipal bond outstanding interest | 5,945.5 | 5,945.5 | 3,264.4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Municipal bond debt service outstanding | 15,909.1 | 15,909.1 | 7,968.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partners Capital Contribution |  |  |  | 594.5 |  |  |  |  |  |  |  |  |  |  |  | 14.5 |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  |  |  | 96.90% | 88.40% |  |  |  |  |  |  |  |  |  |  |  |
Surplus Notes |  |  |  | 503.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Statutory Accounting Practices, Statutory Capital and Surplus, Balance |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 445.7 |  |  |  |  |  |  |
Percentage of par value of policy reinsured |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.00%
Income (Loss) from Continuing Operations before Income Taxes, Domestic |  |  |  |  | 3.8 | 10.5 | 13.4 | 28.2 |  |  | (13.1) | (15.1) | (29.7) | (60.2) |  |  |  |  |  |  |  |
Interest income (expense), surplus notes | 3.9 | 11.8 |  |  |  | 10.1 |  | 30.2 |  |  | (3.9) | (10.1) | (11.8) | (30.2) |  |  |  |  |  |  |  |
Number of years of change in interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 | 3 |
Financial Guarantee Insurance Contracts, Unearned Premium Revenue | $ 23.4 | $ 23.4 | $ 13.2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8.00% | 3.13% |  |  |
Year of U.S. Treasury Rate |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
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- Definition Amount of unearned premium revenue under contracts issued by an insurance entity that provide protection to the holder of a financial obligation from a financial loss in the event of a default. + References No definition available. + Details
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- Definition The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(1)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Total contributions made by each class of partners (i.e., general, limited and preferred partners). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 + Details
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- Definition The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.23(c)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 24 -Subparagraph c -Article 7 + Details
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- Definition Financial instruments issued by insurance entities (surplus notes) that are includable in surplus for statutory accounting purposes as prescribed or permitted by state laws and regulations that are liabilities of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6486086&loc=d3e24387-158525 + Details
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