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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Collateralized loan obligations
Changes in Level 3
Beginning balance	$ 3,119
Total gains or losses
Included in other comprehensive income	7
Purchases, issuances, sales, and settlements
Settlements	(666)
Ending balance	2,492
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	32
States and political subdivisions
Changes in Level 3
Beginning balance	22,226	$ 111
Total gains or losses
Included in other comprehensive income	(501)	9
Purchases, issuances, sales, and settlements
Purchases	10,994
Settlements	(20,359)	(78)
Ending balance	12,360	0
Transfers out of Level 3		(42)
Mortgage servicing rights
Changes in Level 3
Beginning balance	6,489	5,847
Total gains or losses
Included in earnings (or changes in net assets)		(1,394)
Purchases, issuances, sales, and settlements
Issuances	951	1,148
Settlements	(402)	(526)
Ending balance	6,684	$ 5,075
Changes in Level 3 (liabilities)
Included in earnings (or changes in net assets)	$ (354)

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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 the income statement for 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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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Amount of gain (loss) recognized in other comprehensive income (loss) for 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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-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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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 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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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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