Disclosures about Fair Value Measurements and Financial Instruments - Schedule of assets measured and recorded at fair value on a non-recurring basis (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Impaired loan with carrying value	$ 266,000	$ 263,000
Specific valuation allowance	8,000	8,000
Impaired loans	258,000	255,000
Fair Value Measurements, Nonrecurring Basis [Member]
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Impaired loans	258,000	255,000
Other real estate owned		37,000
Fair Value Measurements, Nonrecurring Basis [Member] \| Impaired loans
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Impaired loans	$ 258,000	$ 255,000
Valuation Techniques	Appraisal of collateral (1)	Appraisal of collateral(1)
Fair Value Measurements, Nonrecurring Basis [Member] \| Other real estate owned
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Other real estate owned		$ 37,000
Valuation Techniques		Appraisal of collateral (1)
Fair Value Measurements, Nonrecurring Basis [Member] \| Minimum \| Impaired loans
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Appraisal adjustments	0.00%	0.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Minimum \| Other real estate owned
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Appraisal adjustments		0.00%
Liquidation expenses		21.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Maximum \| Impaired loans
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Appraisal adjustments	100.00%	100.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Maximum \| Other real estate owned
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Appraisal adjustments		57.00%
Liquidation expenses		134.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Wgtd Ave \| Impaired loans
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Appraisal adjustments	3.00%	3.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Wgtd Ave \| Other real estate owned
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Appraisal adjustments		38.00%
Liquidation expenses		30.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Level 1 [Member]
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Impaired loans	$ 0	$ 0
Other real estate owned		0
Fair Value Measurements, Nonrecurring Basis [Member] \| Level 2 [Member]
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Impaired loans	0	0
Other real estate owned		0
Fair Value Measurements, Nonrecurring Basis [Member] \| Level 3 [Member]
DISCLOSURES ABOUT FAIR VALUE MEASUREMENTS
Impaired loans	$ 258,000	255,000
Other real estate owned		$ 37,000

Fair value appraisal of adjustments.

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Fair value liquidation expenses.

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Amount of impaired loan with carrying value.

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Description of the valuation processes in place for fair value measurements categorized within Level 3 of the fair value hierarchy.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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Fair value of firm holdings in securities classified as other. Includes pledged and unpledged holdings.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
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Amount of allowance for credit losses related to recorded investment.

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Fair value portion of receivables, including, but not limited to, trade account receivables, note receivables, and loan receivables.

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-SubTopic 10
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