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Municipal Bond Guarantee (Tables) | 3 Months Ended
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Mar. 31, 2013
Schedule of insured obligations [Abstract] |
Schedule of Municipal Guarantee Insured Obligations [Table Text Block] | The following table provides a schedule of BAM's insured obligations:
|  | March 31, 2013 |  | December 31, 2012
Contracts issued and outstanding |  | 105 |  |  | 3 |
Remaining weighted average contract period (in years) |  | 13.1 |  |  | 10.4 |
Contractual debt service outstanding (in millions): |  |  |  |
Principal |  | $ | 698.6 |  |  | $ | 25.8 |
Interest |  | $ | 497.6 |  |  | $ | 8.9 |
Unearned premium revenue |  | $ | 2.0 |  |  | $ | .1 |

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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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