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Municipal Bond Guarantee (Tables) | 3 Months Ended
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Mar. 31, 2019
Guarantees [Abstract] |
Schedule of Municipal Bond Guarantee Insured Obligations | The following table presents a schedule of BAM’s insured obligations as of March 31, 2019 and December 31, 2018:
|  | March 31, 2019 |  | December 31, 2018
Contracts outstanding |  | 7,786 |  |  | 7,525 |
Remaining weighted average contract period outstanding (in years) |  | 10.7 |  |  | 10.7 |
Contractual debt service outstanding (in millions): |  |  |  |
Principal |  | $ | 53,715.2 |  |  | $ | 52,201.6 |
Interest |  | 27,348.9 |  |  | 26,560.3 |
Total debt service outstanding |  | $ | 81,064.1 |  |  | $ | 78,761.9 |
Gross unearned insurance premiums |  | $ | 179.6 |  |  | $ | 176.0 |
Financial Guarantee Insurance Contracts, Premium Received over Contract Period | The following table presents a schedule of BAM’s future premium revenues as of March 31, 2019:
Millions |  | March 31, 2019
April 1, 2019 - December 31, 2019 |  | $ | 12.2 |
January 1, 2020 - March 31, 2020 |  | 3.9 |
April 1, 2020 - June 30, 2020 |  | 3.9 |
July 1, 2020 - September 30, 2020 |  | 3.9 |
October 1, 2020 - December 31, 2020 |  | 3.8 |
Total 2020 |  | 15.5 |
2021 |  | 14.5 |
2022 |  | 13.6 |
2023 |  | 12.8 |
2024 |  | 12.0 |
2025 and thereafter |  | 99.0 |
Total gross unearned insurance premiums |  | $ | 179.6 |
Schedule of Net Written Premiums | The following table presents a schedule of net written premiums included in White Mountains’s HG Global/BAM segment for the three months ended March 31, 2019 and 2018:
|  | Three Months Ended March 31,
Millions |  | 2019 |  | 2018
Written premiums: |  |  |  |
Direct |  | $ | 7.9 |  |  | $ | 6.4 |
Assumed |  | — |  |  | — |
Gross written premiums |  | $ | 7.9 |  |  | $ | 6.4 |
Earned premiums: |  |  |  |
Direct |  | $ | 3.7 |  |  | $ | 3.0 |
Assumed |  | 0.5 |  |  | — |
Gross earned premiums |  | $ | 4.2 |  |  | $ | 3.0 |

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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://fasb.org/us-gaap/role/ref/legacyRef -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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