Employee Benefits (Summary of options) (Details) - 2020 EIP - Stock options - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Number of Shares
Options outstanding at beginning of year	439,596
Options Expired	(1,666)
Options outstanding at March 31, 2022	437,930	439,596
Options exercisable at March 31, 2022	142,331
Weighted - Average Exercise Price
Weighted - Average Exercise Price, beginning of year	$ 6.62
Weighted - Average Exercise Price, expired	6.57
Weighted - Average Exercise Price, end of period	6.62	$ 6.62
Weighted - Average Exercise Price, exercisable	$ 6.62
Weighted-Average Contractual Term
Weighted-Average Contractual Term, outstanding	8 years 5 months 1 day	8 years 7 months 17 days
Weighted-Average Contractual Term, exercisable	8 years 5 months 1 day

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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