Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) loan	Mar. 31, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 237	$ 350
Post-Modification Recorded Balance	$ 246	$ 363
Number of Loans \| loan	8	5
Real estate loans - Commercial and farmland
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance		$ 107
Post-Modification Recorded Balance		$ 241
Number of Loans \| loan		3
Real estate loans - Residential
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 214	$ 121
Post-Modification Recorded Balance	$ 222	$ 122
Number of Loans \| loan	5	2
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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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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