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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
US States and Political Subdivisions Debt Securities [Member]
Changes in Level 3
Beginning balance	$ 4,319	$ 5,419
Total gains or losses
Included in earnings (or changes in net assets)		(16)
Included in other comprehensive income	812	(216)
Purchases, issuances, sales, and settlements
Purchases	748	12,900
Settlements	(312)	(13,297)
Ending balance	5,560	4,790
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	(7)
Mortgage Servicing Rights [Member]
Changes in Level 3
Beginning balance	4,224	5,935
Total gains or losses
Included in earnings (or changes in net assets)		(2,463)
Purchases, issuances, sales, and settlements
Issuances	1,298	1,813
Settlements	(1,042)	(275)
Ending balance	5,320	$ 5,010
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	$ 840

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

+ References

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

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