Investment Securities - Additional Information (Details)	12 Months Ended
Dec. 31, 2020 USD ($) Security	Dec. 31, 2019 USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of available-for-sale securities in unrealized loss position less than 12 months \| Security	5
Number of available-for-sale securities in unrealized loss position 12 months or greater \| Security	1
Proceeds from sales of investment securities available-for-sale	$ 1,676,000	$ 16,361,000
Gross realized gain on sale of available -for-sale securities	20,000	213,000
Gross realized loss on sale of available -for-sale securities	0	66,000
Carrying value of available-for-sale securities pledged to secure public deposits	24,005,000	3,818,000
Collateral Pledged
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Carrying value of available-for-sale securities pledged to secure public deposits	$ 2,300,000	$ 3,800,000
Government Agency Securities
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of available-for-sale securities in unrealized loss position less than 12 months \| Security	3
Trust Preferred Securities
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of available-for-sale securities in unrealized loss position less than 12 months \| Security	3
Carrying value of available-for-sale securities pledged to secure public deposits	$ 2,614,000

Available for sale and held to maturity securities.

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Amount 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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of realized gain on 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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