Securities - Additional Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Proceeds from sale of available-for-sale securities	$ 0	$ 0
Mutual fund - CRA qualified	3,773,000	3,628,000
Other Income
Schedule Of Available For Sale Securities [Line Items]
Unrealized holding gains on investment	79,000	72,000
Securities Available For Sale, At Fair Value \| ASU 2016-01
Schedule Of Available For Sale Securities [Line Items]
Mutual fund - CRA qualified	(2,500,000)
Other Investments \| ASU 2016-01
Schedule Of Available For Sale Securities [Line Items]
Mutual fund - CRA qualified	2,500,000
Collateral Pledged
Schedule Of Available For Sale Securities [Line Items]
Number of securities pledged as collateral	$ 0	$ 0
Stockholder's Equity \| Credit Concentration Risk \| Non-US Government and Agency Securities
Schedule Of Available For Sale Securities [Line Items]
Concentration risk, percentage	10.00%	10.00%

Community reinvestment act qualified mutual fund.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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.

+ References

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