Stock Option Plans - Liberty Bell Stock Option Plan (Details) - Liberty 2004 Stock Option Plan - Stock options	1 Months Ended	9 Months Ended
Jul. 31, 2017 $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares
Equity Compensation
Contractual life	10 years
Vesting period (in years)	5 years
Conversion ratio, stock based compensation	0.2857
Number of options converted \| shares	48,225
Exercise price of option converted	$ 1.18
Number of options outstanding after conversion \| shares	13,771
Average price	$ 4.14
Employees
Equity Compensation
Exercise price of option exercised		$ 4.14
Shares \| shares		2,355	2,355
Average price		$ 4.14	$ 4.14
Exercised in 2020 (Per share)		$ 4.14
Amount \| $		$ 9,750	$ 9,750
Directors
Equity Compensation
Number of options exercised \| shares		1,028
Exercise price of option exercised		$ 4.14
Shares \| shares		5,326	6,354
Exercised in 2020 (Shares) \| shares		(1,028)
Average price		$ 4.14	$ 4.14
Exercised in 2020 (Per share)		$ 4.14
Amount \| $		$ 22,051	$ 26,307
Exercised in 2020 (in dollars) \| $		$ (4,256)

The number of options issued in conversion in a noncash transaction.

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The number of options converted in a noncash transaction in a business combination.

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Ratio applied to the conversion of options in a business combination.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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 option holders acquired shares when converting their stock options into shares.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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