Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Nature of Operations and Summary of Significant Accounting Policies
Effective income tax rate reconciliation, change in enacted tax rate, amount	$ 0
Maximum deferrable under annual incentive award percent	50.00%
Dilutive effects	$ 0	$ 0
Federal Home Loan and Reserve Bank Stock
Nature of Operations and Summary of Significant Accounting Policies
Cash, uninsured amount	$ 21,541,000	$ 74,752,000
Company buildings \| Minimum
Nature of Operations and Summary of Significant Accounting Policies
Estimated useful lives (in years)	10 years
Company buildings \| Maximum
Nature of Operations and Summary of Significant Accounting Policies
Estimated useful lives (in years)	39 years
Furniture and equipment \| Minimum
Nature of Operations and Summary of Significant Accounting Policies
Estimated useful lives (in years)	3 years
Furniture and equipment \| Maximum
Nature of Operations and Summary of Significant Accounting Policies
Estimated useful lives (in years)	7 years
Computer software \| Minimum
Nature of Operations and Summary of Significant Accounting Policies
Estimated useful lives (in years)	1 year
Computer software \| Maximum
Nature of Operations and Summary of Significant Accounting Policies
Estimated useful lives (in years)	3 years

Maximum deferrable under annual incentive award, percent.

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- Definition

Summary Of Significant Accounting Policies [Line Items]

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- Definition

The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

+ References

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- Definition

Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=123427490&loc=d3e32059-109318

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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