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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Changes in Level 3
Transfers into Level 3	$ 0
Asset-backed Securities
Changes in Level 3
Beginning balance	2,270	$ 16,740
Transfers out of Level 3		(14,885)
Total gains or losses
Included in earnings		(11)
Included in other comprehensive income	(69)	239
Purchases, issuances, sales, and settlements
Purchases	1,209	782
Settlements	(156)	(595)
Ending balance	3,254	2,270
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	13,059	12,501
Total gains or losses
Included in earnings	(125)	(135)
Included in other comprehensive income	(444)	998
Purchases, issuances, sales, and settlements
Settlements	(594)	(305)
Ending balance	11,896	13,059
Mortgage Servicing rights
Changes in Level 3
Beginning balance	10,344	11,189
Total gains or losses
Included in earnings	(160)	(924)
Purchases, issuances, sales, and settlements
Issuances	753	580
Settlements	(563)	(501)
Ending balance	$ 10,374	$ 10,344

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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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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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.

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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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