Municipal Bond Guarantee Insurance - Schedule of Municipal Bond Guarantee Insured Obligations (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($) contract	Dec. 31, 2023 USD ($) contract
HG Global
Guarantor Obligations [Line Items]
Contracts outstanding | contract	15,524	14,485
Remaining weighted average contract period (in years)	12 years 3 months 18 days	12 years 2 months 12 days
Outstanding first loss exposure from policies assumed (in millions)	$ 17,667,200	$ 16,341,000
Total gross unearned insurance premiums	$ 287,000	$ 273,900
HG/BAM
Guarantor Obligations [Line Items]
Remaining weighted average contract period (in years)		11 years 1 month 6 days
Outstanding first loss exposure from policies assumed (in millions)		$ 109,673,800
Total gross unearned insurance premiums		325,800
Total debt service outstanding		165,686,000
Interest		$ 56,012,200