Securities - Additional Information (Details)	12 Months Ended
Dec. 31, 2020 USD ($) Security	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Proceeds from calls and principal repayments	$ 16,166,000	$ 8,196,000	$ 11,707,000
Net gains on sales and/or calls of securities available for sale	992,000	79,000	838,000
Securities available for sale purchased	35,801,000	27,626,000	12,372,000
Proceeds from sale of securities, available for sale	$ 18,762,000	13,871,000	$ 0
Number of debt securities temporarily impaired \| Security	5
Aggregate fair value	$ 8,466,000	19,160,000
Other-than-temporary impairment in securities	0
Other-than-temporary impairment loss recognized	0
Unrealized loss position, carrying amount	0
Unrealized loss position for more than 12 months	0	44,000
Carrying value of pledged securities	13,100,000	$ 16,600,000
5 Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Aggregate fair value	$ 8,500,000

Debt securities available for sale unrealized loss position carrying amount.

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Amount of accumulated unrealized loss on investment in debt security 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 allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of realized gain (loss) 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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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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 unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings.

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Amount of cash outflow to acquire 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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The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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Amount of cash inflow from maturity, prepayment and call 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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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.

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