Loans and the Allowance for Loan Losses, Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Unpaid Principal Balance	$ 15,057	$ 18,970
Recorded Investment, Without Valuation Allowance	14,423	15,249
Recorded Investment, With Valuation Allowance	634	931
Associated Allowance	104	116
Average Recorded Investment	15,937	18,268
Interest Income Recognized	3	549
Mortgage Loans on Real Estate [Member]
Receivables [Abstract]
Unpaid Principal Balance	14,770	18,548
Recorded Investment, Without Valuation Allowance	14,211	15,171
Recorded Investment, With Valuation Allowance	559	711
Associated Allowance	96	105
Average Recorded Investment	15,645	17,779
Interest Income Recognized	3	544
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member]
Receivables [Abstract]
Unpaid Principal Balance	1,877	2,057
Recorded Investment, Without Valuation Allowance	1,788	1,686
Recorded Investment, With Valuation Allowance	89	239
Associated Allowance	44	51
Average Recorded Investment	1,934	2,073
Interest Income Recognized	0	66
Mortgage Loans on Real Estate [Member] \| Commercial [Member]
Receivables [Abstract]
Unpaid Principal Balance	11,861	15,254
Recorded Investment, Without Valuation Allowance	11,861	12,721
Recorded Investment, With Valuation Allowance	0	0
Associated Allowance	0	0
Average Recorded Investment	12,683	14,232
Interest Income Recognized	0	455
Mortgage Loans on Real Estate [Member] \| Construction [Member]
Receivables [Abstract]
Unpaid Principal Balance	445	509
Recorded Investment, Without Valuation Allowance	354	417
Recorded Investment, With Valuation Allowance	91	92
Associated Allowance	17	18
Average Recorded Investment	487	665
Interest Income Recognized	1	7
Mortgage Loans on Real Estate [Member] \| Second Mortgages [Member]
Receivables [Abstract]
Unpaid Principal Balance	355	496
Recorded Investment, Without Valuation Allowance	208	347
Recorded Investment, With Valuation Allowance	147	148
Associated Allowance	32	33
Average Recorded Investment	309	508
Interest Income Recognized	2	15
Mortgage Loans on Real Estate [Member] \| Equity Line of Credit [Member]
Receivables [Abstract]
Unpaid Principal Balance	232	232
Recorded Investment, Without Valuation Allowance	0	0
Recorded Investment, With Valuation Allowance	232	232
Associated Allowance	3	3
Average Recorded Investment	232	301
Interest Income Recognized	0	1
Commercial [Member]
Receivables [Abstract]
Unpaid Principal Balance	287	384
Recorded Investment, Without Valuation Allowance	212	78
Recorded Investment, With Valuation Allowance	75	220
Associated Allowance	8	11
Average Recorded Investment	292	446
Interest Income Recognized	0	5
Consumer [Member] \| Other Consumer Loans [Member]
Receivables [Abstract]
Unpaid Principal Balance	0	38
Recorded Investment, Without Valuation Allowance	0	0
Recorded Investment, With Valuation Allowance	0	0
Associated Allowance	0	0
Average Recorded Investment	0	43
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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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