Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Borrowings and FHLB Advances [Abstract]
Available federal funds lines	$ 100,000	$ 100,000
Available credit with FHLB	365,600	374,700
Short-Term Borrowings [Abstract]
Overnight repurchase agreements	6,204	6,619
Total short-term borrowings	6,204	6,619
Maximum month-end outstanding balance	6,606	9,080
Average outstanding balance during the period	$ 7,032	$ 21,092
Average interest rate (year-to-date)	0.10%	0.19%
Average interest rate at end of period	0.10%	0.10%
Long-Term Borrowings [Abstract]
Federal Reserve Bank Borrowings	$ 10,995	$ 28,550
Minimum [Member]
Borrowings and FHLB Advances [Abstract]
Overnight repurchase agreements maturity period	1 day
Maximum [Member]
Borrowings and FHLB Advances [Abstract]
Overnight repurchase agreements maturity period	4 days
Paycheck Protection Program Liquidity Facility [Member]
Long-Term Borrowings [Abstract]
Federal Reserve Bank Borrowings	$ 11,000
Paycheck Protection Program Liquidity Facility [Member] \| Maximum [Member]
Long-Term Borrowings [Abstract]
Maturity term of borrowings from origination	24 months
Citizens Acquisition [Member]
Long-Term Borrowings [Abstract]
Loan maturity date	Apr. 01, 2023
Loans outstanding		$ 1,400
Interest rate		2.61%

Federal funds lines available balance.

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Overnight repurchase agreements maturity term in days.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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Weighted average interest rate of short-term debt outstanding calculated over time.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, maximum month-end borrowings during the period.

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