Stockholders' Equity - Additional information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested share-based compensation awards granted	$ 10.6
Unrecognized compensation cost related to non-vested share-based compensation awards granted year	2022
Stock option exercisable	1,780,405
Antidilutive shares excluded from the computation of diluted earnings per common share	24,743,605	10,243,260
2011 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	481,898
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	270,250
Vesting period of shares	3 years
Fair market value of RSUs granted	$ 1.2
Series B Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of Series A preferred stock	(700)
Series A preferred shares outstanding	2,400
Series A Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of Series A preferred stock	0
Series A preferred shares outstanding	2,093,155
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of Series A preferred stock	3,888,888
Board of Directors and Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	2,031,033
Fair market value of shares granted	$ 4.1
Term of options granted period	10 years
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of shares	3 years
Employees [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	47,000
Board of Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of shares, Description	Options granted to members of the Board of Directors vest ratably through 2022

Employee service share based compensation non vested awards compensation cost to be recognized year

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Share based compensation arrangement by share based payment award equity instruments other than options grants in period fair value.

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Share based compensation arrangements by share based payment award term of options granted.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Unrecognized cost of unvested share-based compensation awards.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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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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