Credit Quality and Nonperforming Assets - Troubled Debt Restructurings - Tabular Disclosure (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($) item	Jun. 30, 2019 USD ($) item	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($) item
Financing Receivable, Modifications [Line Items]
Pre-Modification Outstanding Recorded Investment	$ 1,617,000	$ 368,000	$ 1,955,000	$ 571,000
Post-Modification Outstanding Recorded Investment	1,616,000	368,000	1,954,000	571,000
Reserve Difference	59,000	(45,000)	59,000	(67,000)
Reserve	69,000	48,000	69,000	50,000
Finance receivables modified as TDRs within the previous twelve months			0	0
Commercial, Residential, and Farm Land Real Estate Portfolio Segment [Member] \| Real Estate Sector [Member]
Financing Receivable, Modifications [Line Items]
Pre-Modification Outstanding Recorded Investment	1,589,000	244,000	1,927,000	344,000
Post-Modification Outstanding Recorded Investment	1,588,000	244,000	1,926,000	344,000
Reserve Difference	58,000	0	58,000
Reserve	$ 67,000	$ 1,000	$ 67,000	$ 1,000
Commercial, Residential, and Farm Land Real Estate Portfolio Segment [Member] \| Real Estate Sector [Member] \| Other construction/land [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 86,000	$ 0	$ 86,000
Post-Modification Outstanding Recorded Investment	85,000	0	85,000
Reserve Difference	40,000	0	40,000
Reserve	$ 41,000	$ 0	$ 41,000
Commercial, Residential, and Farm Land Real Estate Portfolio Segment [Member] \| Real Estate Sector [Member] \| 1-4 Family - Closed-End [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 1,325,000	$ 0	$ 1,325,000
Post-Modification Outstanding Recorded Investment	1,325,000	0	1,325,000
Reserve Difference	10,000	0	10,000
Reserve	$ 17,000	$ 0	$ 17,000
Commercial, Residential, and Farm Land Real Estate Portfolio Segment [Member] \| Real Estate Sector [Member] \| Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	1	0	2
Pre-Modification Outstanding Recorded Investment	$ 0	$ 244,000		$ 344,000
Post-Modification Outstanding Recorded Investment	0	244,000		344,000
Reserve Difference	0	0
Reserve	$ 0	$ 1,000		$ 1,000
Commercial, Residential, and Farm Land Real Estate Portfolio Segment [Member] \| Real Estate Sector [Member] \| Multi-Family Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	0	0
Reserve Difference	0	0
Reserve	$ 0	$ 0
Commercial, Residential, and Farm Land Real Estate Portfolio Segment [Member] \| Real Estate Sector [Member] \| Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	0	2	0
Pre-Modification Outstanding Recorded Investment	$ 178,000	$ 0	$ 516,000
Post-Modification Outstanding Recorded Investment	178,000	0	516,000
Reserve Difference	8,000	0	8,000
Reserve	$ 9,000	$ 0	$ 9,000
Commercial, Residential, and Farm Land Real Estate Portfolio Segment [Member] \| Real Estate Sector [Member] \| Farmland [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	0	0
Reserve Difference	0	0
Reserve	$ 0	$ 0
Agricultural Portfolio Segment [Member] \| Agricultural Sector [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	0	0
Reserve Difference	0	0
Reserve	$ 0	$ 0
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1	2	1	4
Pre-Modification Outstanding Recorded Investment	$ 28,000	$ 74,000	$ 28,000	$ 168,000
Post-Modification Outstanding Recorded Investment	28,000	74,000	28,000	168,000
Reserve Difference	1,000	0	1,000	(20,000)
Reserve	$ 2,000	$ 45,000	$ 2,000	$ 46,000
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	0	1	0	2
Pre-Modification Outstanding Recorded Investment	$ 0	$ 50,000		$ 59,000
Post-Modification Outstanding Recorded Investment	0	50,000		59,000
Reserve Difference	0	(45,000)		(47,000)
Reserve	$ 0	$ 2,000		$ 3,000

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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