Loans and Allowance for Loan Losses Schedule of Loans by Impairment Method (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Loans, Allowance for Loan Losses [Line Items]
Loans, individually evaluated for impairment	$ 517	$ 1,022
Loans, collectively evaluated for impairment	1,457,958	1,400,198
Loans	1,458,475	1,401,220
Commercial loans [Member]
Loans, Allowance for Loan Losses [Line Items]
Loans, individually evaluated for impairment	0	126
Loans, collectively evaluated for impairment	316,716	333,888
Loans	316,716	334,014
Construction, land and land development [Member]
Loans, Allowance for Loan Losses [Line Items]
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	249,453	205,610
Loans	249,453	205,610
1-4 family residential first mortgages [Member]
Loans, Allowance for Loan Losses [Line Items]
Loans, individually evaluated for impairment	94	108
Loans, collectively evaluated for impairment	49,275	47,076
Loans	49,369	47,184
Home equity [Member]
Loans, Allowance for Loan Losses [Line Items]
Loans, individually evaluated for impairment	53	317
Loans, collectively evaluated for impairment	14,505	17,740
Loans	14,558	18,057
Commercial real estate [Member]
Loans, Allowance for Loan Losses [Line Items]
Loans, individually evaluated for impairment	370	471
Loans, collectively evaluated for impairment	819,774	787,529
Loans	820,144	788,000
Consumer and other loans [Member]
Loans, Allowance for Loan Losses [Line Items]
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	8,235	8,355
Loans	$ 8,235	$ 8,355

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=84173941&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=82891408&loc=d3e4428-111522

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