Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($) loan	Jun. 30, 2017 USD ($) loan	Jun. 30, 2018 USD ($) loan	Jun. 30, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 122	$ 973	$ 359	$ 1,323
Post-Modification Recorded Balance	$ 125	$ 696	$ 371	$ 1,059
Number of Loans \| loan	2	9	10	14
Commercial and industrial loans
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance		$ 394		$ 394
Post-Modification Recorded Balance		$ 170		$ 170
Number of Loans \| loan		1		1
Real estate loans - Commercial and farmland
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance		$ 250		$ 357
Post-Modification Recorded Balance		$ 250		$ 491
Number of Loans \| loan		3		6
Real estate loans - Residential
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 122	$ 329	$ 336	$ 450
Post-Modification Recorded Balance	$ 125	$ 276	$ 347	$ 398
Number of Loans \| loan	2	5	7	7
Real estate loans - Home equity
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance			$ 16	$ 122
Post-Modification Recorded Balance			$ 16
Number of Loans \| loan			2
Individuals' loans for household and other personal expenditures
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance			$ 7
Post-Modification Recorded Balance			$ 8
Number of Loans \| loan			1

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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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