Loans and Allowance for Loan Losses - Troubled Debt Restructuring (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017 contract	Dec. 31, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0
Construction and Land Development [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 278
Post-Modification Outstanding Recorded Investment		$ 278
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 164
Post-Modification Outstanding Recorded Investment		$ 164

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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