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Municipal Bond Guarantee Insurance (Tables) | 12 Months Ended
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Dec. 31, 2016
Insurance [Abstract] |
Financial Guarantee Insurance Contracts, Premium Received over Contract Period [Table Text Block] | The following table is a schedule of BAM’s expected premiums to be collected as of December 31, 2016:
Millions |  | December 31, 2016
January 1, 2017 - March 31, 2017 |  | $ | 1.9 |
April 1, 2017 - June 30, 2017 |  | 1.8 |
July 1, 2017 - September 30, 2017 |  | 1.8 |
October 1, 2017 - December 31, 2017 |  | 1.8 |
|  | 7.3 |
2018 |  | 7.0 |
2019 |  | 6.6 |
2020 |  | 6.3 |
2021 |  | 5.9 |
2022 and thereafter |  | 49.9 |
Total |  | $ | 83.0 |
Schedule of Insured Obligations | The following table provides a schedule of BAM’s insured obligations:
|  | December 31, 2016 |  | December 31, 2015
Contracts outstanding |  | 4,807 |  |  | 3,103 |
Remaining weighted average contract period (in years) |  | 10.8 |  |  | 12.8 |
Contractual debt service outstanding (in millions): |  |  |  |
Principal |  | $ | 33,057.3 |  |  | $ | 22,556.0 |
Interest |  | $ | 16,396.6 |  |  | $ | 11,984.4 |
Gross unearned insurance premiums |  | $ | 83.0 |  |  | $ | 50.2 |

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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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