The maximum amount of compensation expense incurred on the reporting period.

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- Definition

Fair value of option exchange from merger.

+ References

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Fair value of option exchange from merger per share.

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- Definition

Share based compensation arrangement by share based payment award conversion of outstanding stock options.

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- Definition

The Maximum Option vested as percentage of total option grant during the year.

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- Definition

The period of performance for options under LTIP.

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No definition available.

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Description about the Period in which option vested or expired.

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No definition available.

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- Definition

Unrecognized compensation expense of reporting period.

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No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Number of shares authorized for issuance under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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

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Stock Compensation Plans - Additional information (Details) - USD ($)	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	37,461			37,461		17,700
Conversion of outstanding stock options	39,983			39,983
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Vested Percentage, Year				20.00%
Stock Option Period, Description				All options expire ten years from the date of grant. Vested options of retirees expire on the earlier of the scheduled expiration date or three months after the retirement date
Fair value of option exchange from merger		$ 461,000		$ 461,000
Fair value of option exchange from merger per share				$ 11.52
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options	$ 3,000			$ 3,000
Employee Service Share Based Compensation Nonvested Awards, Total Compensation Cost Not Yet Recognized, Period For Recognition (in years)				3 months 3 days
Allocated Share-based Compensation Expense	974,000		$ 559,000	$ 3,000,000.0	$ 1,500,000
Compensation Expense, Maximum	2,700,000			2,700,000
Unrecognized Compensation Expense	$ 2,100,000			$ 2,100,000
Equity Plan 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	900,000			900,000
Short Term Equity Incentive Plan 2015 [Member]
Stock Option Period, Description				The final amount of benefits under the STIPs is determined as of December 31 of the same year and paid out in cash in the first quarter of the following year
Short Term Equity Incentive Plan 2015 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%			10.00%
Short Term Equity Incentive Plan 2015 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	45.00%			45.00%
Long Term Equity Incentive Plan 2015 [Member]
Stock Option Period, Description				The amount of benefit under each LTIP will be determined individually at the end of the 36 month performance period ending December 31. The benefits earned under each LTIP will be paid out in equity in the first quarter following the end of the performance period. The participants are required to be employed on the day of payout in order to receive the payment.
Share-based Compensation, Performance Period				3 years
Long Term Equity Incentive Plan 2015 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	20.00%			20.00%
Long Term Equity Incentive Plan 2015 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	45.00%			45.00%
Restricted Stock Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				13,349
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				1 year
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	52,392			52,392
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	144,937			144,937		158,470
Short Term Equity Incentive Plan 2011 [Member]
Allocated Share-based Compensation Expense				$ 2,300,000		$ 1,200,000