Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Changes in Level 3
Transfers into Level 3		$ 0
Asset-backed Securities
Changes in Level 3
Beginning balance	$ 15,012
Transfers out of Level 3	(14,885)
Total gains or losses
Included in other comprehensive income	226
Purchases, issuances, sales, and settlements
Settlements	(342)
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	(11)
Collateralized loan obligations.
Changes in Level 3
Beginning balance	6,770
Transfers out of Level 3	(6,764)
Total gains or losses
Included in other comprehensive income	(6)
States and political subdivisions
Changes in Level 3
Beginning balance	14,229	15,236
Total gains or losses
Included in other comprehensive income	(132)	(1,333)
Purchases, issuances, sales, and settlements
Purchases	406
Issuances		519
Settlements	(338)	(1,015)
Ending balance	14,066	13,309
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	(99)	(98)
Mortgage Servicing Rights [Member]
Changes in Level 3
Beginning balance	11,189	7,097
Purchases, issuances, sales, and settlements
Issuances	420	756
Settlements	(380)	(776)
Ending balance	11,461	11,461
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	$ 232	$ 4,384

No definition available.

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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.

+ References

No definition available.

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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.

+ References

No definition available.

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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
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- Definition

Amount of issuances 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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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 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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No definition available.

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Amount of settlement 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 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
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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.

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

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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

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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