Loans and Allowance for Loan Losses, Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Receivables [Abstract]
Unpaid Principal Balance	$ 18,970	$ 20,830
Recorded Investment, Without Valuation Allowance	15,249	16,049
Recorded Investment, With Valuation Allowance	931	2,426
Associated Allowance	116	95
Average Recorded Investment	18,268	18,626
Interest Income Recognized	549	742
Mortgage Loans on Real Estate [Member]
Receivables [Abstract]
Unpaid Principal Balance	18,548	19,715
Recorded Investment, Without Valuation Allowance	15,171	15,213
Recorded Investment, With Valuation Allowance	711	2,426
Associated Allowance	105	95
Average Recorded Investment	17,779	17,197
Interest Income Recognized	544	712
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member]
Receivables [Abstract]
Unpaid Principal Balance	2,057	2,873
Recorded Investment, Without Valuation Allowance	1,686	2,499
Recorded Investment, With Valuation Allowance	239	316
Associated Allowance	51	52
Average Recorded Investment	2,073	2,525
Interest Income Recognized	66	90
Mortgage Loans on Real Estate [Member] \| Commercial [Member]
Receivables [Abstract]
Unpaid Principal Balance	15,254	15,262
Recorded Investment, Without Valuation Allowance	12,721	11,622
Recorded Investment, With Valuation Allowance	0	1,644
Associated Allowance	0	1
Average Recorded Investment	14,232	13,541
Interest Income Recognized	455	579
Mortgage Loans on Real Estate [Member] \| Construction [Member]
Receivables [Abstract]
Unpaid Principal Balance	509	814
Recorded Investment, Without Valuation Allowance	417	721
Recorded Investment, With Valuation Allowance	92	92
Associated Allowance	18	18
Average Recorded Investment	665	406
Interest Income Recognized	7	23
Mortgage Loans on Real Estate [Member] \| Second Mortgages [Member]
Receivables [Abstract]
Unpaid Principal Balance	496	473
Recorded Investment, Without Valuation Allowance	347	318
Recorded Investment, With Valuation Allowance	148	135
Associated Allowance	33	14
Average Recorded Investment	508	464
Interest Income Recognized	15	20
Mortgage Loans on Real Estate [Member] \| Equity Line of Credit [Member]
Receivables [Abstract]
Unpaid Principal Balance	232	293
Recorded Investment, Without Valuation Allowance	0	53
Recorded Investment, With Valuation Allowance	232	239
Associated Allowance	3	10
Average Recorded Investment	301	261
Interest Income Recognized	1	0
Commercial [Member] \| Commercial and Industrial Loans [Member]
Receivables [Abstract]
Unpaid Principal Balance	384	1,115
Recorded Investment, Without Valuation Allowance	78	836
Recorded Investment, With Valuation Allowance	220	0
Associated Allowance	11	0
Average Recorded Investment	446	1,388
Interest Income Recognized	5	30
Consumer [Member]
Receivables [Abstract]
Unpaid Principal Balance	38	0
Recorded Investment, Without Valuation Allowance	0	0
Recorded Investment, With Valuation Allowance	0	0
Associated Allowance	0	0
Average Recorded Investment	43	41
Interest Income Recognized	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 14A
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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