Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Percentage of level 3 invested assets in total investment portfolio	7.40%		7.40%
Net investment gains (losses) included in net income related to financial assets	$ 0.9	$ 6.5	$ 3.2	$ 7.6
Net investment gains (losses) included in net income related to financial liabilities	$ 4.6	$ 0.7	$ 14.4	$ 8.2

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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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