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Municipal Bond Guarantee Insurance (Tables) | 12 Months Ended
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Dec. 31, 2015
Insurance [Abstract] |
Financial Guarantee Insurance Contracts, Premium Received over Contract Period [Table Text Block] | The following table is a schedule of BAM’s future premium revenues as of December 31, 2015:
Millions |  | December 31, 2015
January 1, 2016 - March 31, 2016 |  | $ | 1.1 |
April 1, 2016 - June 30, 2016 |  | 1.1 |
July 1, 2016 - September 30, 2016 |  | 1.1 |
October 1, 2016 - December 31, 2016 |  | 1.1 |
|  | 4.4 |
2017 |  | 4.3 |
2018 |  | 4.1 |
2019 |  | 3.8 |
2020 |  | 3.6 |
2020 and thereafter |  | 30.0 |
Total |  | $ | 50.2 |
Schedule of Insured Obligations | The following table provides a schedule of BAM’s insured obligations:
|  | December 31, 2015 |  | December 31, 2014
Contracts outstanding |  | 3,103 |  |  | 1,750 |
Remaining weighted average contract period (in years) |  | 12.8 |  |  | 12.8 |
Contractual debt service outstanding (in millions): |  |  |  |
Principal |  | $ | 22,556.0 |  |  | $ | 12,362.5 |
Interest |  | $ | 11,984.4 |  |  | $ | 7,086.9 |
Gross unearned insurance premiums |  | $ | 50.2 |  |  | $ | 27.6 |

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- Definition Tabular disclosure of financial guarantee insurance contracts in which premiums are received over the contract period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
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- Definition [Table Text Block] for Schedule of Municipal Guarantee Insured Obligations [Table] + References No definition available. + Details
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