Fair Value Measurements - Mortgage Servicing Rights - Level 3 (Details) - Recurring - Significant Unobservable Inputs (Level 3) - Mortgage servicing rights (MSRs) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Fair value of assets
Balance at beginning of period	$ 2,875	$ 2,781	$ 2,931	$ 2,713
Total (losses) or gains (realized/unrealized): Included in earnings	(279)	(49)	(373)	(31)
Total (losses) or gains (realized/unrealized): Included in other comprehensive income	0	0
Purchases	0	0
Sales	0	0
Issues	61	81	99	131
Settlements	0	0
Balance at end of period	$ 2,657	$ 2,813	$ 2,657	$ 2,813

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

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.

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- Definition

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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- Definition

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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- Definition

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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- Definition

Amount of sale 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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