Loans and Allowance for Loan Losses Schedule of Allowance for Loan Losses Based on Impairment Method (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loans, Allowance for Credit Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	$ 567	$ 751
Allowance for loan losses, collectively evaluated for impairment	14,400	12,856
Allowance for loan losses	14,967	13,607	$ 13,791	$ 15,529
Commercial loan [Member]
Loans, Allowance for Credit Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	142	150
Allowance for loan losses, collectively evaluated for impairment	4,227	4,265
Allowance for loan losses	4,369	4,415	4,199	4,116
Construction, land and land development [Member]
Loans, Allowance for Credit Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	0	200
Allowance for loan losses, collectively evaluated for impairment	2,338	1,951
Allowance for loan losses	2,338	2,151	3,032	4,616
1-4 family residential first mortgages [Member]
Loans, Allowance for Credit Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	508	466
Allowance for loan losses	508	466	613	637
Home equity [Member]
Loans, Allowance for Credit Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	270	229
Allowance for loan losses, collectively evaluated for impairment	211	305
Allowance for loan losses	481	534	403	568
Commercial real estate [Member]
Loans, Allowance for Credit Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	155	172
Allowance for loan losses, collectively evaluated for impairment	7,099	5,841
Allowance for loan losses	7,254	6,013	5,485	5,564
Consumer and other loans [Member]
Loans, Allowance for Credit Losses [Line Items]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	17	28
Allowance for loan losses	$ 17	$ 28	$ 59	$ 28

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

+ Details

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+ References

No definition available.

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- Definition

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=49124121&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=49124121&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 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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