Fair Value - Level 3 Assets (Details) - Level 3 - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	$ 15,650	$ 23,753	$ 22,559	$ 31,881
Included in earnings	(124)	(748)	(386)	(892)
Included in other comprehensive income	(80)	(151)	318	(1,381)
Purchases	1,645	5,837	3,945	9,821
Sales	(306)	(5,367)	(1,038)	(9,130)
Transfers into Level 3	1,984	42,640	3,652	47,649
Transfers out of Level 3	(2,371)	(6,569)	(12,652)	(18,553)
Ending balance	16,398	59,395	16,398	59,395
Available-for-sale Securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	10,951	21,736	18,780	29,798
Included in earnings	(155)	(597)	(379)	(675)
Included in other comprehensive income	(80)	(151)	318	(1,381)
Purchases	1,645	5,837	2,987	9,821
Sales	(306)	(5,367)	(1,038)	(9,130)
Transfers into Level 3	1,984	42,640	3,652	47,649
Transfers out of Level 3	(2,371)	(6,569)	(12,652)	(18,553)
Ending balance	11,668	57,529	11,668	57,529
Corporate debt securities \| Available-for-sale Securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	4,503	10,927	3,686	5,256
Included in earnings	14	(8)	(14)	5
Included in other comprehensive income	37	(334)	122	(389)
Purchases	779	950	1,532	4,934
Sales	(100)	(2,611)	(745)	(3,119)
Transfers into Level 3	1,655	2,225	3,153	5,774
Transfers out of Level 3	(1,765)	(5,040)	(2,611)	(6,352)
Ending balance	5,123	6,109	5,123	6,109
Commercial mortgage-backed securities \| Available-for-sale Securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	6,415	10,597	10,910	15,728
Included in earnings	(169)	(588)	(360)	(704)
Included in other comprehensive income	(117)	181	100	(658)
Purchases	866	0	1,455	0
Sales	(185)	(2,665)	(185)	(3,165)
Transfers into Level 3	329	2,875	466	4,335
Transfers out of Level 3	(606)	(1,529)	(5,853)	(6,665)
Ending balance	6,533	8,871	6,533	8,871
Residential mortgage-backed securities \| Available-for-sale Securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	33	212	4,184	8,814
Included in earnings	0	(1)	(5)	24
Included in other comprehensive income	0	2	96	(334)
Purchases	0	4,887	0	4,887
Sales	(21)	(91)	(108)	(2,846)
Transfers into Level 3	0	37,540	33	37,540
Transfers out of Level 3	0	0	(4,188)	(5,536)
Ending balance	12	42,549	12	42,549
Equity securities \| Equity securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	4,699	2,017	3,779	2,083
Included in earnings	31	(151)	(7)	(217)
Included in other comprehensive income	0	0	0	0
Purchases	0	0	958	0
Sales	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Ending balance	$ 4,730	$ 1,866	$ 4,730	$ 1,866

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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- 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

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- Definition

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
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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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

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

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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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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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.

+ References

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-Subparagraph (c)
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-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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