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Fair Value Measurements, Measured On Recurring Basis Significant Unobservable Inputs (Details) - Fair Value, Measurements, Recurring [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 2018
Available-for-sale securities [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Balance, beginning of period | $ 0 |  | $ 4,802 |
Transfer to Level 3 from Level 2 | 0 | [1] | 0 | [2]
Purchases | 0 |  | 0 |
Proceeds from sales | 0 |  | 0 |
Redemptions and distributions | 0 |  | (3,045) |
Other comprehensive income (loss) | 0 |  | 134 |
Balance, end of period | 0 |  | 1,891 |
Available-for-sale securities [Member] | Municipal and other tax-exempt securities [Member] | Mortgage banking revenue [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Gain (loss) recognized in earnings | 0 |  | 0 |
Available-for-sale securities [Member] | Other debt securities [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Balance, beginning of period | 472 |  | 472 |
Transfer to Level 3 from Level 2 | 0 | [1] | 0 | [2]
Purchases | 0 |  | 0 |
Proceeds from sales | 0 |  | 0 |
Redemptions and distributions | 0 |  | 0 |
Other comprehensive income (loss) | 0 |  | 0 |
Balance, end of period | 472 |  | 472 |
Available-for-sale securities [Member] | Other debt securities [Member] | Mortgage banking revenue [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Gain (loss) recognized in earnings | 0 |  | 0 |
Residential mortgage loans held for sale [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Balance, beginning of period | 15,207 |  | 12,299 |
Transfer to Level 3 from Level 2 | 982 | [1] | 2,156 | [2]
Purchases | 0 |  | 0 |
Proceeds from sales | (381) |  | (324) |
Redemptions and distributions | 0 |  | 0 |
Other comprehensive income (loss) | 0 |  | 0 |
Balance, end of period | 15,776 |  | 13,871 |
Residential mortgage loans held for sale [Member] | Mortgage banking revenue [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Gain (loss) recognized in earnings | $ (32) |  | $ (260) |
[1] | Recurring transfers to Level 3 from Level 2 consist of residential mortgage loans intended for sale to U.S. government agencies that fail to meet conforming standards.
[2] | Recurring transfers to Level 3 from Level 2 consist of residential mortgage loans intended for sale to U.S. government agencies that fail to meet conforming standards.

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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