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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, 2025 USD ($)
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Guarantor Obligations [Line Items] |
January 1, 2026 - March 31, 2026 | $ 7.1
April 1, 2026 - June 30, 2026 | 7.0
July 1, 2026 - September 30, 2026 | 6.9
October 1, 2026 - December 31, 2026 | 6.8
Total 2026 | 27.8
2027 | 26.4
2028 | 24.8
2029 | 23.3
2030 | 21.9
2031 and thereafter | 203.7
Total gross unearned insurance premiums | $ 327.9

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