Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($) loan	Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 2,640	$ 195	$ 4,159	$ 456
Post-Modification Recorded Balance	$ 2,652	$ 185	$ 4,208	$ 439
Number of Loans \| loan	34	3	45	8
Commercial and industrial loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 0		$ 654
Post-Modification Recorded Balance	$ 0		$ 654
Number of Loans \| loan	0		3
Commercial and farmland
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 0		$ 565
Post-Modification Recorded Balance	$ 0		$ 565
Number of Loans \| loan	0		2
Residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 2,314	$ 195	$ 2,614	$ 456
Post-Modification Recorded Balance	$ 2,326	$ 185	$ 2,663	$ 439
Number of Loans \| loan	30	3	36	8
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 307		$ 307
Post-Modification Recorded Balance	$ 307		$ 307
Number of Loans \| loan	2		2
Individuals' loans for household and other personal expenditures
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 19		$ 19
Post-Modification Recorded Balance	$ 19		$ 19
Number of Loans \| loan	2		2

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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