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, 2021	Dec. 31, 2020
Disclosures about Fair Value Measurements and Financial Instruments
Impaired loan with carrying value	$ 7,000	$ 266,000
Specific valuation allowance	6,000	8,000
Impaired loans	1,000	258,000
Other real estate owned and repossessed assets	8,000
Fair Value Measurements, Nonrecurring Basis
Disclosures about Fair Value Measurements and Financial Instruments
Impaired loans	1,000	258,000
Fair Value Measurements, Nonrecurring Basis \| Other real estate owned
Disclosures about Fair Value Measurements and Financial Instruments
Other real estate owned and repossessed assets	8,000
Fair Value Measurements, Nonrecurring Basis \| Level 3
Disclosures about Fair Value Measurements and Financial Instruments
Impaired loans	1,000	258,000
Other real estate owned and repossessed assets	8,000
Fair Value Measurements, Nonrecurring Basis \| Level 3 \| Impaired loans
Disclosures about Fair Value Measurements and Financial Instruments
Impaired loans	$ 1,000	$ 258,000
Valuation Techniques	Appraisal of collateral	Appraisal of collateral
Fair Value Measurements, Nonrecurring Basis \| Level 3 \| Other real estate owned
Disclosures about Fair Value Measurements and Financial Instruments
Other real estate owned and repossessed assets	$ 8,000
Valuation Techniques	Appraisal of collateral
Appraisal adjustments	30.00%
Liquidation expenses	3.00%
Fair Value Measurements, Nonrecurring Basis \| Level 3 \| Minimum \| Impaired loans
Disclosures about Fair Value Measurements and Financial Instruments
Appraisal adjustments	0.00%	0.00%
Fair Value Measurements, Nonrecurring Basis \| Level 3 \| Maximum \| Impaired loans
Disclosures about Fair Value Measurements and Financial Instruments
Appraisal adjustments	100.00%	100.00%
Fair Value Measurements, Nonrecurring Basis \| Level 3 \| Wgtd Ave \| Impaired loans
Disclosures about Fair Value Measurements and Financial Instruments
Appraisal adjustments	89.00%	3.00%
Fair Value Measurements, Nonrecurring Basis \| Level 3 \| Wgtd Ave \| Other real estate owned
Disclosures about Fair Value Measurements and Financial Instruments
Appraisal adjustments	30.00%
Liquidation expenses	3.00%

Fair value appraisal of adjustments.

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- Definition

Fair value liquidation expenses.

+ References

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- Definition

Amount of impaired loan with carrying value.

+ References

No definition available.

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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.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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- Definition

Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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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=120391452&loc=d3e13212-122682

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-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(7))
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13728-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 944
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-Subparagraph (SX 210.7-03(a)(5))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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