Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Summary of Fair Value Assumptions

The principal assumptions used in applying the model were as follows:

	For the Year Ended December 31, 2017
Assumptions:
Risk-free interest rate	1.5% - 2.0%
Expected life	2.5 - 3 years
Expected volatility	50% - 60%
Dividends	0.0%

Schedule of Earnings Per Share, Basic and Diluted

	Years Ended December 31,
	2017		2016			2015
	(In thousands, except share and per share data)
Numerator:
Net income (loss) attributable to common stockholders	$	17,929	$	(6,439	)	$	(12,602	)
Denominator:
Weighted-average common shares, basic	25,353,966		22,837,263			22,548,932
Weighted-average common shares, diluted*	26,269,727		22,837,263			22,548,932
Net income (loss) per common share:
Basic:	$	0.71	$	(0.28	)	$	(0.56	)
Diluted:	$	0.68	$	(0.28	)	$	(0.56	)
* The diluted earnings per common share included 438,712 unvested Restricted Stock Units and the weighted average effect of 477,048 stock options that are potentially dilutive to earnings per share for the twelve months ended December 31, 2017, since the exercise price of such securities was less than the average market price during the period.

Summary of Components Excluded from Computation of Diluted Net Loss Per Share

Potentially dilutive common shares from employee equity plans and warrants are determined by applying the treasury stock method to the assumed exercise of warrants and share options and were excluded from the computation of diluted net loss per share because their inclusion would be anti-dilutive and consist of the following: 

	December 31,
	2017	2016	2015
Stock options	2,341,340	1,607,347	1,510,832
Restricted stock units	438,712	185,260	408,710
Warrants	2,355,506	—	—
Total	5,135,558	1,792,607	1,919,542