Loans and Allowance for Loan Losses Schedule of Allowance for Loan Losses by Impairment Method (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Loans, Allowance for Loan Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	$ 146	$ 503
Allowance for loan losses, collectively evaluated for impairment	16,212	15,609
Allowance for loan losses	16,358	16,112
Commercial loans [Member]
Loans, Allowance for Loan Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	0	91
Allowance for loan losses, collectively evaluated for impairment	3,668	3,790
Allowance for loan losses	3,668	3,881
Construction, land and land development [Member]
Loans, Allowance for Loan Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	2,722	2,639
Allowance for loan losses	2,722	2,639
1-4 family residential first mortgages [Member]
Loans, Allowance for Loan Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	334	317
Allowance for loan losses	334	317
Home equity [Member]
Loans, Allowance for Loan Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	23	276
Allowance for loan losses, collectively evaluated for impairment	194	202
Allowance for loan losses	217	478
Commercial real estate [Member]
Loans, Allowance for Loan Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	123	136
Allowance for loan losses, collectively evaluated for impairment	9,188	8,561
Allowance for loan losses	9,311	8,697
Consumer and other loans [Member]
Loans, Allowance for Loan Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	106	100
Allowance for loan losses	$ 106	$ 100

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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No definition available.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for 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 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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