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Stock Based Compensation - Vested Options (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted non-vested options (shares)		67,000	207,000	979,790
Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted non-vested options (shares)	16,176	9,286	23,121	28,621
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted non-vested options (shares)	1,551		235,170	6,740

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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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