Fair Value - Level 3 Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Roll forward of level 3 fair value measurements on a recurring basis
Fair value, asset, recurring basis, unobservable input reconciliation, asset, gain (loss), statement of other comprehensive income or comprehensive income	Other comprehensive income	Other comprehensive income
Fair value, asset, recurring basis, unobservable input reconciliation, gain (loss), statement of income or comprehensive income	Net investment income	Net realized and unrealized investment (losses) gains
Level 3
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	$ 31,881	$ 26,224
Included in earnings	(2,055)	(351)
Included in other comprehensive income	(3,520)	(783)
Purchases	13,177	13,489
Sales	(18,864)	(11,120)
Transfers into Level 3	60,635	31,098
Transfers out of Level 3	(58,695)	(26,676)
Ending balance	22,559	31,881
Level 3 \| Available-for-sale securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	29,798	26,224
Included in earnings	(1,751)	(346)
Included in other comprehensive income	(3,520)	(783)
Purchases	11,177	12,489
Sales	(18,864)	(11,120)
Transfers into Level 3	60,635	28,915
Transfers out of Level 3	(58,695)	(25,581)
Ending balance	18,780	29,798
Level 3 \| Corporate debt securities \| Available-for-sale securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	5,256	5,825
Included in earnings	2	34
Included in other comprehensive income	(437)	68
Purchases	6,290	5,502
Sales	(4,810)	(2,681)
Transfers into Level 3	9,689	4,290
Transfers out of Level 3	(12,304)	(7,782)
Ending balance	3,686	5,256
Level 3 \| Collateralized debt obligations \| Available-for-sale securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	0	0
Included in earnings		0
Included in other comprehensive income		0
Purchases		750
Sales		0
Transfers into Level 3		0
Transfers out of Level 3		(750)
Ending balance		0
Level 3 \| Commercial mortgage-backed securities \| Available-for-sale securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	15,728	19,462
Included in earnings	(1,060)	(375)
Included in other comprehensive income	(1,132)	(782)
Purchases	0	3,073
Sales	(3,825)	(5,378)
Transfers into Level 3	11,494	11,933
Transfers out of Level 3	(10,295)	(12,205)
Ending balance	10,910	15,728
Level 3 \| Residential mortgage-backed securities \| Available-for-sale securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	8,814	937
Included in earnings	(693)	(5)
Included in other comprehensive income	(1,951)	(69)
Purchases	4,887	576
Sales	(10,229)	(2,229)
Transfers into Level 3	39,452	12,692
Transfers out of Level 3	(36,096)	(3,088)
Ending balance	4,184	8,814
Level 3 \| Other debt securities \| Available-for-sale securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	0	0
Included in earnings		0
Included in other comprehensive income		0
Purchases		2,588
Sales		(832)
Transfers into Level 3		0
Transfers out of Level 3		(1,756)
Ending balance		0
Level 3 \| Equity securities \| Equity securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	2,083	0
Included in earnings	(304)	(5)
Included in other comprehensive income	0	0
Purchases	2,000	1,000
Sales	0	0
Transfers into Level 3	0	2,183
Transfers out of Level 3	0	(1,095)
Ending balance	$ 3,779	$ 2,083

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

No definition available.

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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

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-Publisher FASB
-Name Accounting Standards Codification
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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).

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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.

+ References

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-Publisher FASB
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- Definition

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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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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-Publisher FASB
-Name Accounting Standards Codification
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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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- Definition

Indicates line item in statement in which net income is reported that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

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

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