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Contracts Accounted for as Insurance - Narrative (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Guarantor Obligations [Line Items]
Weighted average risk-free rates for U.S. dollar denominated financial guaranty insurance obligations	4.86%	4.15%
Minimum
Guarantor Obligations [Line Items]
Weighted average risk-free rates for U.S. dollar denominated financial guaranty insurance obligations	4.51%	3.82%
Maximum
Guarantor Obligations [Line Items]
Weighted average risk-free rates for U.S. dollar denominated financial guaranty insurance obligations	5.45%	4.69%
Foreign Currency Concentration Risk | Premiums Receivable | Premiums Receivable
Guarantor Obligations [Line Items]
Percentage of installment premiums denominated in currencies other than the U.S. dollar	70.00%	74.00%

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- Definition

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This element represents the weighted average risk free rate used to discount the claim liability related to financial guarantee insurance contracts.

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