Fair Value Measurements - Changes in Level 3 (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Changes in Level 3
Transfers into Level 3		$ 0
Asset-backed Securities
Changes in Level 3
Transfers into Level 3	$ 15,012,000
Transfers out of Level 3	15,000,000.0
Purchases, issuances, sales, and settlements
Ending balance	15,012,000
Collateralized loan obligations.
Changes in Level 3
Transfers into Level 3	6,770,000
Transfers out of Level 3	6,800,000
Purchases, issuances, sales, and settlements
Ending balance	6,770,000
States and political subdivisions
Changes in Level 3
Beginning balance	15,236,000	4,319,000
Total gains or losses
Included in earnings (or changes in net assets)	(136,000)	(20,000)
Included in other comprehensive income (loss)	(86,000)	801,000
Purchases, issuances, sales, and settlements
Purchases	519,000	11,063,000
Settlements	(1,304,000)	(927,000)
Ending balance	14,229,000	15,236,000
Mortgage Servicing Rights [Member]
Changes in Level 3
Beginning balance	7,097,000	4,224,000
Total gains or losses
Included in earnings (or changes in net assets)	4,106,000	2,420,000
Purchases, issuances, sales, and settlements
Issuances	915,000	1,612,000
Settlements	(929,000)	(1,159,000)
Ending balance	$ 11,189,000	$ 7,097,000

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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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).

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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