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Stock-Based Compensation - Vested Options (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted non-vested options (shares)	2,000	2,000	479,500	300,000
Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted non-vested options (shares)	13,861	12,091	25,672	24,643
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted non-vested options (shares)	1,500	2,602	515,960	311,991

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- Definition

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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- Definition

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

+ References

No definition available.

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