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Fair Value (Additional Information) (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Impaired loans, carrying amount | [1] |  |  | $ 7,229,000
Valuation allowance for impaired loans |  |  |  | 3,371,000
Other real estate carried at fair value less cost to sell |  | $ 0 |  | 0
Other real estate, adjustments to carrying value less costs to charged to earnings |  | 0 |  | 0
Fair Value, Measurements, Recurring |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Securities |  | 875,787,000 |  | 854,825,000
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Securities |  | 3,482,000 |  | 4,021,000
Loans Held-for-sale |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Gains/(losses) from changes in fair value included in earnings |  | 5,000 | $ 134,000 |
Obligations of State and Political Subdivisions | Fair Value, Measurements, Recurring |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Securities |  | 326,864,000 |  | 324,300,000
Gains/(losses) included in earnings attributable to other changes in fair value |  | (16,000) | $ (9,000) |
Obligations of State and Political Subdivisions | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Securities |  | 3,482,000 |  | 4,021,000
Collateral-dependent loans |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Impaired loans, carrying amount |  | 19,005,000 |  | 5,574,000
Valuation allowance for impaired loans |  | 8,876,000 |  | 2,971,000
Collateral-dependent loans | Impaired Loans |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Increase (decrease) in allowance for loan losses |  | $ 1,849,000 |  | $ (1,149,000)
[1] | Total recorded investment in loans includes $13,929 in accrued interest.

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + 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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- Definition Amount of gain (loss) recognized in other comprehensive income (OCI) 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)(1a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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