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Municipal Bond Guarantee Reinsurance - Schedule of Municipal Guarantee Insurance Contracts, Premium Received Over Contract Period (Details) - Variable Interest Entity, Primary Beneficiary - HG Global $ in Millions | Dec. 31, 2024 USD ($)
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Guarantor Obligations [Line Items] |
January 1, 2025 - March 31, 2025 | $ 6.8
April 1, 2025 - June 30, 2025 | 6.6
July 1, 2025 - September 30, 2025 | 6.5
October 1, 2025 - December 31, 2025 | 6.4
Total 2025 | 26.3
2026 | 24.7
2027 | 23.3
2028 | 21.8
2029 | 20.2
2030 and thereafter | 181.0
Total gross unearned insurance premiums | $ 297.3

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