Disclosures about Fair Value Measurements and Financial Instruments - Schedule of assets measured and recorded at fair value on a non-recurring basis (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	$ 733,000	$ 0
Fair Value Measurements, Nonrecurring Basis [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	733,000	0
Other real estate owned	57,000	157,000
Fair Value Measurements, Nonrecurring Basis [Member] \| Impaired loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	$ 674,000	$ 0
Valuation Techniques	Appraisal of collateral (1)	Appraisal of collateral(1)
Fair Value Measurements, Nonrecurring Basis [Member] \| Impaired loans \| Discounted cash flows
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	$ 59,000
Valuation Techniques	Discounted cash flows
Fair Value Measurements, Nonrecurring Basis [Member] \| Other real estate owned
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other real estate owned	$ 57,000	$ 157,000
Valuation Techniques	Appraisal ofcollateral (1)	Appraisal of collateral (1)
Fair Value Measurements, Nonrecurring Basis [Member] \| Minimum \| Impaired loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Appraisal adjustments	0.00%	100.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Minimum \| Other real estate owned
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Appraisal adjustments	0.00%	0.00%
Liquidation expenses	12.00%	21.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Maximum \| Impaired loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Appraisal adjustments	100.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Maximum \| Impaired loans \| Discounted cash flows
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Probability of loss adjustment	15.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Maximum \| Other real estate owned
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Appraisal adjustments	44.00%	39.00%
Liquidation expenses	114.00%	195.00%
Fair Value Measurements, Nonrecurring Basis [Member] \| Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	$ 0	$ 0
Other real estate owned	0	0
Fair Value Measurements, Nonrecurring Basis [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	0	0
Other real estate owned	0	0
Fair Value Measurements, Nonrecurring Basis [Member] \| Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	733,000	0
Other real estate owned	$ 57,000	$ 157,000

Fair value appraisal of adjustments.

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- Definition

Fair value liquidation expenses.

+ References

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- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

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- Definition

Percentage of fair value probability of loss adjustments.

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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.

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No definition available.

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- Definition

Fair value of firm holdings in securities classified as other. Includes pledged and unpledged holdings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(5))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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