Fair Value Disclosures (Narrative Disclosures) (Details) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Fair Value Inputs, Assets, Quantitative Information
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, 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
Fair value, liabilities, transfers out of level 3	$ 0	$ 0	0
Minimum
Fair Value Inputs, Assets, Quantitative Information
Quantification of unobservable inputs for level 3 values for impaired loans	5.00%	5.00%
Maximum
Fair Value Inputs, Assets, Quantitative Information
Quantification of unobservable inputs for level 3 values for impaired loans	75.00%	75.00%
Weighted Average
Fair Value Inputs, Assets, Quantitative Information
Quantification of unobservable inputs for level 3 values for impaired loans	17.00%	17.00%
Impaired loans
Fair Value Inputs, Assets, Quantitative Information
Assets measured on a non-recurring basis, fair value	$ 16,552,000	$ 16,552,000	15,147,000
Fair Value Measurements - Level 3 Inputs \| Impaired loans
Fair Value Inputs, Assets, Quantitative Information
Assets measured on a non-recurring basis, fair value	5,833,000	5,833,000	5,084,000
Fair Value Measurements - Level 3 Inputs \| Foreclosed properties
Fair Value Inputs, Assets, Quantitative Information
Assets measured on a non-recurring basis, fair value	$ 0	$ 0	$ 0

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

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Quantification of unobservable inputs for Level 3 values for impaired loans

+ References

No definition available.

+ Details

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

+ Details

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

+ Details

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