Investment Securities Available-for-Sale - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Federal Reserve and Federal Home Loan Bank stock	$ 33,978		$ 40,104
Allowance for credit losses	$ (78)		(167)
Debt securities as percentage of total investment securities	99.90%
Debt securities weighted average duration	4 years 7 months 6 days
Proceeds from sale/call of available-for-sale securities	$ 28,505	$ 78,030
Holdings of securities of any one issuer	10.00%
Gross realized gains on sales of investment securities	$ 386	822
Noninterest Income	10,587	5,470
Gross realized losses on sales of investment	165	$ 0
Other Assets
Debt Securities, Available-for-sale [Line Items]
Accrued interest on available for sale securities	4,000		3,500
Collateral Pledged
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Restricted	$ 270,000		$ 268,400

Amount of realized gain on investment in debt and equity securities.

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Amount of realized loss on investment in debt and equity securities.

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The total percentage of debt securities.

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Period of time between issuance and maturity of debt securities, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Percent of holdings of securities of any one issuer, other than the U.S. Government and U.S. agency securities, which exceeded shareholders equity.

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of allowance for credit 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 restricted 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 Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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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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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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