Fair Value Measurements, Quantitative Information (Details) - Market Comparables [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 45	$ 264
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Liquidation discount		0.00%
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Liquidation discount		4.00%
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs	7.25%	7.25%
Liquidation discount	4.00%	2.91%
Mortgage Loans on Real Estate [Member] \| Commercial [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 272
Mortgage Loans on Real Estate [Member] \| Commercial [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs	7.78%
Liquidation discount	4.70%
Mortgage Loans on Real Estate [Member] \| Construction [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 74	$ 74
Mortgage Loans on Real Estate [Member] \| Construction [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs	7.25%	7.25%
Liquidation discount	4.00%	4.00%
Mortgage Loans on Real Estate [Member] \| Equity Lines of Credit [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 229	$ 229
Mortgage Loans on Real Estate [Member] \| Equity Lines of Credit [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs	6.70%	7.25%
Liquidation discount	3.70%	4.00%
Consumer [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 100
Consumer [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs	0.00%
Liquidation discount	0.00%
Other Real Estate [Member] \| Commercial [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value	$ 203
Other Real Estate [Member] \| Commercial [Member] \| Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling costs	7.25%
Liquidation discount	10.00%

Adjustment to the value of a property for estimated selling costs to liquidate.

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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