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Fair Value Measurements, Measured On Recurring Basis Significant Unobservable Inputs (Details) - Fair Value, Recurring [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 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 | $ 4,802,000
Transfer to Level 3 from Level 2 | [1] | 0 | 0
Purchases |  | 0 | 0
Redemptions and distributions |  | 0 | (5,095,000)
Proceeds from sales |  | 0 | 0
Other comprehensive income (loss) |  | 0 | 293,000
Balance, end of period |  | 0 | 0
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 |  | 472,000 | 472,000
Transfer to Level 3 from Level 2 | [1] | 0 | 0
Purchases |  | 0 | 0
Redemptions and distributions |  | 0 | 0
Proceeds from sales |  | 0 | 0
Other comprehensive income (loss) |  | 0 | 0
Balance, end of period |  | 472,000 | 472,000
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 |  | 15,207,000 | 12,299,000
Transfer to Level 3 from Level 2 | [1] | 2,449,000 | 6,183,000
Purchases |  | 0 | 0
Redemptions and distributions |  | 0 | 0
Proceeds from sales |  | (9,972,000) | (2,706,000)
Other comprehensive income (loss) |  | 0 | 0
Balance, end of period |  | 8,313,000 | 15,207,000
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 |  | $ 629,000 | $ (569,000)
[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.

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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 income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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