Fair Value Disclosures (Narrative Disclosures) (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Fair value, assets, level 1 to level 2 transfers	$ 0	$ 0	$ 0
Fair value, assets, level 2 to Level 1 transfers	0	0	0
Fair value, assets, transfers into level 3	0	0	0
Fair value, assets, transfers out of level 3	0	0	0
Fair value, liabilities, transfers out of level 3	0	0	0
Fair value, liabilities, level 1 to level 2 transfers	0	0	0
Fair value, liabilities, level 2 to level 1 transfers	0	0	0
Fair value, liabilities, transfers into level 3	$ 0	$ 0	0
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Quantification of unobservable inputs for level 3 values for impaired loans	13.00%	13.00%
Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Quantification of unobservable inputs for level 3 values for impaired loans	75.00%	75.00%
Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Quantification of unobservable inputs for level 3 values for impaired loans	19.00%	19.00%
Fair Value, Measurements, Nonrecurring [Member] \| Impaired loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets, Fair Value Disclosure	$ 24,940,000	$ 24,940,000	15,147,000
Fair Value, Measurements, Nonrecurring [Member] \| Foreclosed properties
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets, Fair Value Disclosure	1,454,000	1,454,000	1,069,000
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value Measurements - Level 3 Inputs \| Impaired loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets, Fair Value Disclosure	4,680,000	4,680,000	5,084,000
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value Measurements - Level 3 Inputs \| Foreclosed properties
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets, Fair Value Disclosure	$ 0	$ 0	$ 0

Fair Value, Assets, Level 1 to Level 2 Transfers, Amount1

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Fair Value, Assets, Level 2 to Level 1 Transfers, Amount1

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Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount1

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Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount1

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Quantification of unobservable inputs for Level 3 values for impaired loans

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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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.

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- Definition

Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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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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-SubTopic 10
-Section 50
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