Loans - Narrative (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) loan	Sep. 30, 2020 USD ($) loan
Loans and Leases Receivable Disclosure [Line Items]
Outstanding balance of high risk loans, minimum	$ 250,000		$ 250,000
Interest income on impaired loans	261,000	$ 104,000	825,000	$ 154,000
Unfunded commitments to lend	0		$ 0
Number of loans that subsequently defaulted \| loan			0	0
Construction, land and land development
Loans and Leases Receivable Disclosure [Line Items]
Loan contracts restructured \| loan			1
Troubled debt restructuring	$ 511,000		$ 511,000

Loan Balance For Reviewing High Risk Loans Minimum

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Amount of interest income on financing receivable on nonaccrual status.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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