Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Changes in Level 3
Transfers into Level 3	$ 0
Collateralized Mortgage 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)
Asset-backed Securities
Changes in Level 3
Beginning balance	2,270	16,741
Transfers out of Level 3		(14,885)
Total gains or losses
Included in earnings		(11)
Included in other comprehensive income	(29)	219
Purchases, issuances, sales, and settlements
Purchases	259	406
Settlements	(15)	(355)
Ending balance	2,485	2,115
Collateralized loan obligations.
Changes in Level 3
Transfers out of Level 3		6,800
States and political subdivisions
Changes in Level 3
Beginning balance	13,059	12,501
Total gains or losses
Included in earnings	(33)	(34)
Included in other comprehensive income	(89)	430
Purchases, issuances, sales, and settlements
Settlements	(34)	(33)
Ending balance	12,903	12,864
Mortgage Servicing rights
Changes in Level 3
Beginning balance	10,344	11,189
Total gains or losses
Included in earnings	172	(471)
Purchases, issuances, sales, and settlements
Issuances	126	120
Settlements	(78)	(54)
Ending balance	$ 10,564	$ 10,784

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.

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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
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-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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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.

+ 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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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 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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- 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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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

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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