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v3.25.1

Municipal Bond Guarantee Insurance - Schedule of Net Written Premiums (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Written premiums: |  |
Direct | $ 0.0 | $ 10.5
Assumed | 6.7 | 0.0
Gross written premiums | 6.7 | 10.5
Earned premiums: |  |
Direct | 0.0 | 7.3
Assumed | 8.2 | 0.5
Gross earned premiums | $ 8.2 | 7.8
HG Global |  |
Written premiums: |  |
Direct |  | 0.0
Assumed |  | 8.9
Gross written premiums |  | 8.9
Earned premiums: |  |
Direct |  | 0.0
Assumed |  | 6.5
Gross earned premiums |  | 6.5
BAM |  |
Written premiums: |  |
Direct |  | 10.5
Assumed |  | 0.0
Gross written premiums |  | 10.5
Earned premiums: |  |
Direct |  | 7.3
Assumed |  | 0.5
Gross earned premiums |  | 7.8
Eliminations |  |
Written premiums: |  |
Direct |  | 0.0
Assumed |  | (8.9)
Gross written premiums |  | (8.9)
Earned premiums: |  |
Direct |  | 0.0
Assumed |  | (6.5)
Gross earned premiums |  | $ (6.5)

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- Definition Amount of earned premiums assumed from other entities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 235 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column D)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477965/944-235-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 + Details
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