Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan	Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 219	$ 194	$ 578	$ 1,517
Post-Modification Recorded Balance	$ 205	$ 201	$ 576	$ 1,261
Number of Loans \| loan	5	4	15	18
Commercial and industrial loans
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance		$ 6		$ 400
Post-Modification Recorded Balance		$ 6		$ 176
Number of Loans \| loan		1		2
Commercial and farmland
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance				$ 357
Post-Modification Recorded Balance				$ 492
Number of Loans \| loan				6
Residential
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 154	$ 120	$ 490	$ 570
Post-Modification Recorded Balance	$ 140	$ 122	$ 487	$ 520
Number of Loans \| loan	4	1	11	8
Home equity
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 65	$ 68	$ 81	$ 190
Post-Modification Recorded Balance	$ 65	$ 73	$ 81	$ 73
Number of Loans \| loan	1	2	3	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://fasb.org/us-gaap/role/ref/legacyRef
-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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