Borrowings (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Borrowings and FHLB Advances [Abstract]
Available federal funds lines	$ 100,000	$ 55,000
Available credit with FHLB	325,800	276,300
Short-Term Borrowings [Abstract]
Overnight repurchase agreements	6,281	11,452
Federal Home Loan Bank advances	0	0
Total short-term borrowings	6,281	11,452
Maximum month-end outstanding balance	9,080	38,138
Average outstanding balance during the period	$ 7,601	$ 27,382
Average interest rate (year-to-date)	0.06%	0.71%
Average interest rate at end of period	0.10%	0.10%
FHLB advances outstanding	$ 38,500	$ 37,000
Federal Reserve Bank Borrowings	37,340	0
Loans outstanding	$ 1,500	1,950
Minimum [Member]
Borrowings and FHLB Advances [Abstract]
Overnight repurchase agreements maturity period	1 day
Short-Term Borrowings [Abstract]
FHLB interest rate	0.88%
Maximum [Member]
Borrowings and FHLB Advances [Abstract]
Overnight repurchase agreements maturity period	4 days
Short-Term Borrowings [Abstract]
FHLB interest rate	2.89%
FHLB Advance One [Member]
Short-Term Borrowings [Abstract]
Maturity date	Feb. 26, 2021
FHLB Advance Two [Member]
Short-Term Borrowings [Abstract]
Maturity date	Mar. 05, 2025
Citizens Acquisition [Member]
Short-Term Borrowings [Abstract]
Maturity date	Apr. 01, 2023
Loans outstanding	$ 1,500	$ 2,000
Interest rate	2.66%

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

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Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

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Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest.

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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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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