Fair Value Measurements, Measured On A Recurring And Nonrecurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Fair value assets and liabilities measured on non-recurring basis [Abstract]
Impaired loans, estimated selling cost	$ 185	$ 188
Recurring [Member]
Securities available for sale [Abstract]
U.S. Agency securities	147,658	170,414
U.S. Treasuries securities		3,000
Obligations of state and political subdivisions	88,243	969,262
Corporate obligations	3,095	3,050
Mortgage-backed securities in government sponsored entities	41,118	37,728
Equity securities in financial institutions	1,659	2,899
Recurring [Member] \| Level I [Member]
Securities available for sale [Abstract]
U.S. Agency securities	0	0
U.S. Treasuries securities		3,000
Obligations of state and political subdivisions	0	0
Corporate obligations	0	0
Mortgage-backed securities in government sponsored entities	0	0
Equity securities in financial institutions	1,659	2,899
Recurring [Member] \| Level II [Member]
Securities available for sale [Abstract]
U.S. Agency securities	147,658	170,414
U.S. Treasuries securities		0
Obligations of state and political subdivisions	88,243	96,926
Corporate obligations	3,095	3,050
Mortgage-backed securities in government sponsored entities	41,118	37,728
Equity securities in financial institutions	0	0
Recurring [Member] \| Level III [Member]
Securities available for sale [Abstract]
U.S. Agency securities	0	0
U.S. Treasuries securities		0
Obligations of state and political subdivisions	0	0
Corporate obligations	0	0
Mortgage-backed securities in government sponsored entities	0	0
Equity securities in financial institutions	0	0
Nonrecurring [Member]
Fair value assets and liabilities measured on non-recurring basis [Abstract]
Impaired Loans	2,064	2,033
Other real estate owned	1,074	839
Nonrecurring [Member] \| Level I [Member]
Fair value assets and liabilities measured on non-recurring basis [Abstract]
Impaired Loans	0	0
Other real estate owned	0	0
Nonrecurring [Member] \| Level II [Member]
Fair value assets and liabilities measured on non-recurring basis [Abstract]
Impaired Loans	0	0
Other real estate owned	0	0
Nonrecurring [Member] \| Level III [Member]
Fair value assets and liabilities measured on non-recurring basis [Abstract]
Impaired Loans	2,064	2,033
Other real estate owned	$ 1,074	$ 839

No definition available.

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- Definition

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No definition available.

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- References

No definition available.

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- Definition

Refers to the estimated selling cost of impaired loans excluded from calculation of fair value.

+ References

No definition available.

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- Definition

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents bonds or similar securities issued by state, city, province, or local governments or their agencies in either the United States or a foreign country. Debt securities issued by state governments or provinces may include bond issuances of US state or foreign authorities. Debt securities issued by political subdivisions or US states may include debt issuances by county, borough, city, or municipal governments.

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No definition available.

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- Definition

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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

Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

+ References

Reference 1: 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=65884687&loc=d3e4437-111522

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=66008989&loc=d3e5162-111524

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