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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
US States and Political Subdivisions Debt Securities [Member]
Changes in Level 3
Beginning balance	$ 5,419	$ 8,165
Total gains or losses
Included in earnings (or changes in net assets)		(8)
Included in other comprehensive income	(325)	171
Purchases, issuances, sales, and settlements
Purchases	6,100	11,325
Settlements	(31)	(97)
Ending balance	11,157	19,556
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	(6)
Mortgage Servicing Rights [Member]
Changes in Level 3
Beginning balance	5,935	7,357
Total gains or losses
Included in earnings (or changes in net assets)		(721)
Purchases, issuances, sales, and settlements
Issuances	307	177
Settlements	(275)	(98)
Ending balance	4,108	$ 6,715
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	$ (1,859)

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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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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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