Cumulative stock options exercised shares.

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Percentage of additional shares from common stock available for stock-based compensation.

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Share based compensation arrangement by share based payment award shares vesting date.

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Aggregate number of common shares reserved for future issuance.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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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.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Sets forth the nature of any other increase or decrease in the number of shares reserved for issuance under the option plan.

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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- Definition

Percentage of vesting of share-based compensation awards.

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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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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended		12 Months Ended
	Nov. 30, 2018	Oct. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Nov. 29, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Stock Options, Granted			339,619
Common stock reserved for future issuance			1,499,934
Common Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Stock Options, Granted			339,619
Options to purchase common stock exercised to date			38,636
2001 Employee Stock Option Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Stock Options, Granted			0
2007 Long Term Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Stock Options, Granted			0
2017 Omnibus Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance, description			The aggregate share reserve will be increased on January 1 of each year commencing in 2018 and ending on and including January 1, 2027 up to an amount equal to the lowest of (i) 4% of the total number of shares of common stock outstanding on a fully diluted basis as of December 31 of the immediately preceding calendar year, and (ii) such number of shares of common stock, if any, determined by the Company’s board of directors.
Percentage of additional shares from common stock available for stock-based compensation			4.00%
2017 Omnibus Incentive Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			1,500,000
2017 Omnibus Incentive Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			5,000,000
2017 Omnibus Incentive Plan [Member] \| Common Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			34,327
2017 Omnibus Incentive Plan [Member] \| Common Stock [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock granted, shares			800,000
Stock granted value			$ 5,000,000
2017 Omnibus Incentive Plan [Member] \| Common Stock [Member] \| Maximum [Member] \| Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock granted, shares			500,000
2018 Inducement Grant Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance					2,000,000
2018 Inducement Grant Plan [Member] \| Common Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			1,465,607
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense, period for recognition			3 years 10 months 28 days
Restricted stock authorized and granted	322,907	2,651	322,907
Restricted stock authorized and granted, value		$ 1,067
Weighted average grant date fair value of restricted stock award	$ 3.59	$ 310.80	$ 3.59
Restricted stock vesting period	4 years	4 years
Fair value of restricted shares that vested			$ 3,878
Repurchase of unvested shares price per share			$ 0.01
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage		50.00%
Share-based compensation arrangement by share-based payment award, shares vesting date	Dec. 01, 2022
Unrecognized compensation expense			$ 1,129,653
Restricted Stock [Member] \| One Year Anniversary [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	25.00%
Restricted Stock [Member] \| 36 Substantially Equal Monthly Installments
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	75.00%
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense, period for recognition			2 years 10 months 24 days
Weighted-average grant date fair value of stock options granted			$ 4.63	$ 64.80
Aggregate intrinsic value for stock options exercised			$ 461,555
Unrecognized compensation cost, stock options			$ 1,292,868