Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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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No definition available.

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- Definition

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

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No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

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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Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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No definition available.

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Stockholders' Equity - The 2017 Plan, Additional Information (Details) - 2017 Plan - USD ($)			5 Months Ended	9 Months Ended
	Feb. 13, 2018	Jan. 04, 2018	Dec. 31, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)			214,000	188,550
Options granted, exercise price (in dollars per share)			$ 37.62	$ 23.49
Compensation not yet recognized				$ 4,500,000
Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	100,000	57,050		31,500
Options granted, exercise price (in dollars per share)	$ 24.79	$ 24.84
Expiration period	10 years	10 years		10 years
Fair value of option granted	$ 2,500,000	$ 1,400,000		$ 476,025
Award vesting period				4 years
Stock based compensation expense				$ 3,900,000	$ 362,986
Options to purchase common stock \| End of one year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%	25.00%
Options to purchase common stock \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	2.0833%	2.0833%
Minimum \| Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, exercise price (in dollars per share)				$ 14.31
Award vesting period				1 year
Maximum \| Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, exercise price (in dollars per share)				$ 19.83
Award vesting period				4 years