Fair Value Measurements, Quantitative Information (Details) - Appraised Collateral Values [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Impaired Loans [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 2,425	$ 1,569
Valuation Technique(s)	Appraised Collateral Values	Appraised Collateral Values
Impaired Loans [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount for time since appraisal	0.00%	0.00%
Selling costs	5.00%	5.00%
Holding period	0 months	6 months
Impaired Loans [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount for time since appraisal	100.00%	100.00%
Selling costs	11.00%	9.00%
Holding period	24 months	12 months
Impaired Loans [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount for time since appraisal	33.77%	30.83%
Selling costs	8.47%	8.35%
Holding period	11 months 5 days	11 months
Other Real Estate Owned [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 844	$ 1,024
Valuation Technique(s)	Appraised Collateral Values	Appraised Collateral Values
Other Real Estate Owned [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount for time since appraisal	17.00%	15.00%
Other Real Estate Owned [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount for time since appraisal	35.00%	65.00%
Other Real Estate Owned [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount for time since appraisal	24.57%	26.26%

Holding period, used as an input to measure fair value.

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- Definition

Percentage of selling costs, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

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

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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.

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- Definition

Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

+ 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 (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

+ 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 (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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