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Share Based Payments - Summary of Stock Option Activity (Parenthetical) (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock options exercised on cashless basis	8,500	20,000
Number of shares withheld	3,280	14,095

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- Definition

Number of common stock shares withheld.

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- Definition

Stock issued during period shares stock options exercised on cashless basis.

+ References

No definition available.

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- References

No definition available.

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