Loans - Additional Information (Details)	12 Months Ended
Dec. 31, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan	Dec. 31, 2017 USD ($)
Financing Receivable Recorded Investment [Line Items]
Interest income recognized on cash basis	$ 0	$ 0	$ 0
Interest income on nonaccrual loans	0	0
Troubled debt restructurings interest income	$ 128,000	$ 177,000
Number of loans identified as troubled debt restructurings \| Loan	4	4
Reserve for loans	$ 18,816,000	$ 17,577,000	$ 13,773,000
Commitments to lend an additional amounts of outstanding loans are classified as TDR's	$ 0	$ 0
Number of loans defaulted \| Loan	0	0
Outstanding balance of purchased credit-impaired loan	$ 0	$ 0
Minimum
Financing Receivable Recorded Investment [Line Items]
Moratorium on loan payments period granted	3 months
Maximum
Financing Receivable Recorded Investment [Line Items]
Moratorium on loan payments period granted	6 months
Specific Reserves
Financing Receivable Recorded Investment [Line Items]
Reserve for loans		44,000
One Loan \| Specific Reserves
Financing Receivable Recorded Investment [Line Items]
Reserve for loans	$ 0	$ 0

Allowance for credit losses reserve change in method of calculating impairment.

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- Definition

Moratorium on loan payment period granted.

+ References

No definition available.

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- Definition

Number of loans identified as troubled debt restructurings.

+ References

No definition available.

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- Definition

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

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- Definition

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

+ References

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=118936363&loc=SL6953682-111524

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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

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ 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
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-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18794-111554

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
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- Definition

The gross interest income that would have been recorded in the period on troubled debt restructurings, if the loans had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period.

+ References

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