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Contracts Accounted for as Insurance - Narrative (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Guarantor Obligations [Line Items]
Weighted average risk-free rates for U.S. dollar denominated financial guaranty insurance obligations	3.84%	4.15%
Minimum
Guarantor Obligations [Line Items]
Weighted average risk-free rates for U.S. dollar denominated financial guaranty insurance obligations	3.44%	3.82%
Maximum
Guarantor Obligations [Line Items]
Weighted average risk-free rates for U.S. dollar denominated financial guaranty insurance obligations	4.87%	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	73.00%	74.00%

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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- Definition

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

+ References

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-SubTopic 40
-Section 50
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- Definition

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