Loans and Allowance for Loan Losses - Summary of Aging Recorded Investment Past-due Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	$ 2,432	$ 3,920
Loans Not Past Due	1,194,090	1,106,526
Total	1,196,522	1,110,446
Real Estate \| Construction and Land Development
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Not Past Due	94,297	89,409
Total	94,297	89,409
Real Estate \| Commercial Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Not Past Due	491,086	501,798
Total	491,086	501,798
Real Estate \| Single-family Residential Mortgages
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	531
Loans Not Past Due	236,636	156,428
Total	237,167	156,428
Commercial \| Other
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	213	343
Loans Not Past Due	225,754	203,500
Total	225,967	203,843
Commercial \| SBA
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	1,688	3,577
Loans Not Past Due	146,317	155,391
Total	148,005	158,968
30-59 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	998	343
30-59 Days Past Due \| Real Estate \| Single-family Residential Mortgages
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	531
30-59 Days Past Due \| Commercial \| Other
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	213	343
30-59 Days Past Due \| Commercial \| SBA
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	254
60-89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	1,434
60-89 Days Past Due \| Commercial \| SBA
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	$ 1,434
Greater Than 89 Days Past Due
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		3,577
Greater Than 89 Days Past Due \| Commercial \| SBA
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		$ 3,577

Financing receivables that are current.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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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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