Loans and Allowance for Loan Losses Schedule of Loans by Impairment Method (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Loans, Allowance for Credit Losses [Line Items]
Loans, individually evaluated for impairment	$ 1,461	$ 2,872
Loans, collectively evaluated for impairment	1,246,288	1,181,779
Loans, gross	1,247,749	1,184,651
Commercial loan [Member]
Loans, Allowance for Credit Losses [Line Items]
Loans, individually evaluated for impairment	142	456
Loans, collectively evaluated for impairment	348,909	316,452
Loans, gross	349,051	316,908
Construction, land and land development [Member]
Loans, Allowance for Credit Losses [Line Items]
Loans, individually evaluated for impairment	60	1,201
Loans, collectively evaluated for impairment	174,542	153,289
Loans, gross	174,602	154,490
1-4 family residential first mortgages [Member]
Loans, Allowance for Credit Losses [Line Items]
Loans, individually evaluated for impairment	352	257
Loans, collectively evaluated for impairment	51,018	53,240
Loans, gross	51,370	53,497
Home equity [Member]
Loans, Allowance for Credit Losses [Line Items]
Loans, individually evaluated for impairment	270	229
Loans, collectively evaluated for impairment	21,479	24,271
Loans, gross	21,749	24,500
Commercial real estate [Member]
Loans, Allowance for Credit Losses [Line Items]
Loans, individually evaluated for impairment	637	729
Loans, collectively evaluated for impairment	643,539	625,209
Loans, gross	644,176	625,938
Consumer and other loans [Member]
Loans, Allowance for Credit Losses [Line Items]
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	6,801	9,318
Loans, gross	$ 6,801	$ 9,318

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.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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