Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Percentage of level 3 invested assets in total investment portfolio	9.20%		9.20%
Net gains/(losses) included in net income	$ 0.2	$ (0.9)	$ 0.2	$ (3.2)
Net investment gains included in net income related to financial liabilities	$ 3.2	$ 6.3	$ 5.6	$ 13.9

Percentage of invested assets in the total investment portfolio in Level 3 carried at fair value on a recurring basis.

No definition available.

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- References

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

+ Details

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

+ Details

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