Fair Value Measurements (Quantitative Information for Assets Measured at Fair Value) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	$ 4,561	$ 8,259
Other real estate owned	355	355
Impaired Loans [Member] \| Appraisal of Collateral [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	$ 1,306	$ 1,574
Weighted average volatility rate	15.00%	8.00%
Other Real Estate Owned [Member] \| Appraisal of Collateral [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other real estate owned		$ 27
Range		22.00%
Weighted average volatility rate		22.00%
Mortgage Servicing Rights [Member] \| Multiple of Annual Servicing Fee [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage servicing rights	$ 215	$ 225
Weighted average volatility rate	371.00%	371.00%
Minimum [Member] \| Impaired Loans [Member] \| Appraisal of Collateral [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range	0.00%	0.00%
Minimum [Member] \| Mortgage Servicing Rights [Member] \| Multiple of Annual Servicing Fee [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range	300.00%	300.00%
Maximum [Member] \| Impaired Loans [Member] \| Appraisal of Collateral [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range	16.00%	13.00%
Maximum [Member] \| Mortgage Servicing Rights [Member] \| Multiple of Annual Servicing Fee [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range	400.00%	400.00%

Mortgage servicing rights.

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ 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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Weighted average expected volatility of stock price.

+ References

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+ References

No definition available.

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04(c)(Schedule III))
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28)
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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