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Municipal Bond Guarantee (Tables) | 9 Months Ended
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Sep. 30, 2017
Guarantees [Abstract] |
Schedule of Municipal Bond Guarantee Insured Obligations | The following table provides a schedule of BAM’s insured obligations:
|  | September 30, 2017 |  | December 31, 2016
Contracts outstanding |  | 5,907 |  |  | 4,807 |
Remaining weighted average contract period outstanding (in years) |  | 10.9 |  |  | 10.8 |
Contractual debt service outstanding (in millions): |  |  |  |
Principal |  | $ | 39,207.5 |  |  | $ | 33,057.3 |
Interest |  | 19,681.0 |  |  | 16,396.6 |
Total debt service outstanding |  | $ | 58,888.5 |  |  | $ | 49,453.9 |
Gross unearned insurance premiums |  | $ | 118.5 |  |  | $ | 82.9 |
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 September 30, 2017:
Millions |  | September 30, 2017
October 1, 2017 - December 31, 2017 |  | $ | 2.5 |
January 1, 2018 - March 31, 2018 |  | 2.5 |
April 1, 2018 - June 30, 2018 |  | 2.5 |
July 1, 2018 - September 30, 2018 |  | 2.5 |
October 1, 2018 - December 31, 2018 |  | 2.4 |
|  | 9.9 |
2019 |  | 9.5 |
2020 |  | 9.2 |
2021 |  | 8.7 |
2022 and thereafter |  | 78.7 |
Total gross unearned insurance premiums |  | $ | 118.5 |

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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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