Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 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	14,092
Total gains or losses
Included in other comprehensive income	423	(938)
Purchases, issuances, sales, and settlements
Purchases	406	1,076
Settlements	(46)	(364)
Ending balance	14,979	13,833
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	(33)	(33)
Mortgage Servicing Rights [Member]
Changes in Level 3
Beginning balance	11,189	7,097
Purchases, issuances, sales, and settlements
Issuances	120	301
Settlements	(54)	(250)
Ending balance	10,784	10,376
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	$ (471)	$ 3,228

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

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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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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-Publisher FASB
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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
-Publisher FASB
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