Loans and Allowance for Loan Losses - Additional Information (Details)	12 Months Ended
Dec. 31, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan
Financing Receivable Modifications [Line Items]
Loans outstanding to directors and officers	$ 3,000	$ 488,000
Loans to directors and officers, additions	85,000	139,000
Loans to directors and officers, repayments	570,000	167,000
Commitments to lend additional funds to borrowers whose loans were on non-accrual status	$ 0	$ 0
Number of loans modified during the period \| Loan	1
Number of loans determined to be troubled debt restructurings \| Loan	3	3
Troubled debt restructuring carrying value	$ 227,000	$ 117,000
Number of TDRs defaulted during the period \| Loan	0	0
Allowance for loan losses includes specific reserve for troubled deb restructurings	$ 87,000,000
Specific reserve for troubled debt restructurings		$ 0
Other real estate owned	163,000
Loans secured by one- to-four family residential properties in process of foreclosure	344,000	$ 351,000
Troubled Debt Restructurings
Financing Receivable Modifications [Line Items]
Troubled debt restructuring carrying value	$ 128,000

Allowance for loan losses includes specific reserve for troubled deb restructurings.

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- Definition

Financing receivable number of loans determined to be troubled debt restructurings.

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Loans and leases receivable nonaccrual status commitment to lend.

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- Definition

Loans secured by one to four family residential properties in process of foreclosure.

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No definition available.

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Specific reserve for troubled debt restructurings.

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No definition available.

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

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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
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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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-Name Accounting Standards Codification
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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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Carrying amount of other real estate not separately disclosed, including, but not limited to, 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. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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