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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
States and political subdivisions
Changes in Level 3
Beginning balance	$ 14,092	$ 4,319
Total gains or losses
Included in earnings (or changes in net assets)		(3)
Included in other comprehensive income	(938)	299
Purchases, issuances, sales, and settlements
Purchases	1,076	58
Settlements	(364)	(32)
Ending balance	13,833	4,641
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	(33)
Mortgage Servicing Rights [Member]
Changes in Level 3
Beginning balance	7,097	4,224
Total gains or losses
Included in earnings (or changes in net assets)		1,485
Purchases, issuances, sales, and settlements
Issuances	301	552
Settlements	(250)	(372)
Ending balance	10,376	$ 5,889
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	$ 3,228

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

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