Fair Value Measurements, Quantitative Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Impaired Loans [Member] \| Commercial Real Estate [Member] \| Income Approach [Member]
Quantitative Information [Abstract]
Fair value	$ 2,608
Unobservable inputs	Capitalization Rate
Impaired Loans [Member] \| Commercial Real Estate [Member] \| Income Approach [Member] \| Minimum [Member]
Quantitative Information [Abstract]
Discount rate	3.25%
Impaired Loans [Member] \| Commercial Real Estate [Member] \| Income Approach [Member] \| Maximum [Member]
Quantitative Information [Abstract]
Discount rate	3.25%
Impaired Loans [Member] \| Commercial Real Estate [Member] \| Income Approach [Member] \| Weighted Average [Member]
Quantitative Information [Abstract]
Discount rate	3.25%
Impaired Loans [Member] \| Residential 1st Mortgage [Member] \| Sales Comparison Approach [Member]
Quantitative Information [Abstract]
Fair value	$ 475
Unobservable inputs	Adjustment for Difference Between Comparable Sales
Impaired Loans [Member] \| Residential 1st Mortgage [Member] \| Sales Comparison Approach [Member] \| Minimum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	1.00%
Impaired Loans [Member] \| Residential 1st Mortgage [Member] \| Sales Comparison Approach [Member] \| Maximum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	4.00%
Impaired Loans [Member] \| Residential 1st Mortgage [Member] \| Sales Comparison Approach [Member] \| Weighted Average [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	3.00%
Impaired Loans [Member] \| Home Equity Lines and Loans [Member] \| Sales Comparison Approach [Member]
Quantitative Information [Abstract]
Fair value	$ 74
Unobservable inputs	Adjustment for Difference Between Comparable Sales
Impaired Loans [Member] \| Home Equity Lines and Loans [Member] \| Sales Comparison Approach [Member] \| Minimum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	1.00%
Impaired Loans [Member] \| Home Equity Lines and Loans [Member] \| Sales Comparison Approach [Member] \| Maximum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	2.00%
Impaired Loans [Member] \| Home Equity Lines and Loans [Member] \| Sales Comparison Approach [Member] \| Weighted Average [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	1.00%
Impaired Loans [Member] \| Commercial [Member] \| Income Approach [Member]
Quantitative Information [Abstract]
Fair value	$ 1,508
Unobservable inputs	Capitalization Rate
Impaired Loans [Member] \| Commercial [Member] \| Income Approach [Member] \| Minimum [Member]
Quantitative Information [Abstract]
Discount rate	2.95%
Impaired Loans [Member] \| Commercial [Member] \| Income Approach [Member] \| Maximum [Member]
Quantitative Information [Abstract]
Discount rate	8.70%
Impaired Loans [Member] \| Commercial [Member] \| Income Approach [Member] \| Weighted Average [Member]
Quantitative Information [Abstract]
Discount rate	3.40%
Other Real Estate [Member] \| Real Estate Construction [Member] \| Sales Comparison Approach [Member]
Quantitative Information [Abstract]
Fair value	$ 873
Unobservable inputs	Adjustment for Difference Between Comparable Sales
Other Real Estate [Member] \| Real Estate Construction [Member] \| Sales Comparison Approach [Member] \| Minimum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%
Other Real Estate [Member] \| Real Estate Construction [Member] \| Sales Comparison Approach [Member] \| Maximum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%
Other Real Estate [Member] \| Real Estate Construction [Member] \| Sales Comparison Approach [Member] \| Weighted Average [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%

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.

No definition available.

+ Details

Name:	us-gaap_AssetsFairValueDisclosureNonrecurring
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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Period Type:	duration

- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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- Details

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- Details

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