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Municipal Bond Guarantee Insurance - Schedule of Net Written Premiums (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Earned premiums: |  |  |  |
Net earned premiums | $ 227.8 | $ 124.3 | $ 430.6 | $ 235.3
HG/BAM |  |  |  |
Written premiums: |  |  |  |
Direct | 17.1 | 13.8 | 26.5 | 21.8
Assumed | 0.0 | 0.0 | 0.0 | 4.5
Net written premiums | 17.1 | 13.8 | 26.5 | 26.3
Earned premiums: |  |  |  |
Direct | 7.9 | 5.6 | 15.5 | 10.9
Assumed | 2.6 | 0.9 | 3.4 | 2.0
Net earned premiums | $ 10.5 | $ 6.5 | $ 18.9 | $ 12.9

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