Investments - Changes in Balance of Level 3 Securities (Details) - Regulation D Private Placement Fixed Income Securities $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)
Summary of changes in Level 3 securities
Beginning balance	$ 55,266
Included in other comprehensive earnings	2,461
Sales	(3,552)
Purchases	7,921
Ending balance	62,096
Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - OCI	$ 2,461
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Other Comprehensive Income	Other comprehensive earnings (loss), net of tax

Amount of unrealized gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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

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Indicates line item in statement in which other comprehensive income (OCI) is reported that includes unrealized gain (loss) from asset measured at fair value using unobservable input (level 3) and still held.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in other comprehensive income (OCI) 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
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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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