Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2017

Equity [Abstract]

Schedule of Number of Shares of Common Stock Reserved for Future Issuance

The Company has reserved for future issuance the following number of shares of common stock:

	June 30, 2017		December 31, 2016
Unvested restricted stock		1,524,058		1,297,054
Common stock options		1,012,833		1,267,329
Shares available for issuance under the 2013 Stock Option and    Incentive Plan		3,170,156		2,398,031
Shares available for issuance under the 2013 Employee Stock    Purchase Plan		788,503		788,503
		6,495,550		5,750,917

Summary of Roll Forward of Restricted Stock Activity Pursuant to the 2010 and 2013 Stock Plan

The following table shows a roll forward of restricted stock activity pursuant to the 2010 Stock Plan and the 2013 Stock Plan:

	Number of Shares
Unvested at December 31, 2016		1,297,054
Granted		719,896
Vested		(417,977	)
Cancelled		(74,915	)
Unvested at June 30, 2017		1,524,058

Summary of Stock Option Activity Under the 2010 Stock Plan and the 2013 Stock Plan

A summary of stock option activity under the 2010 Stock Plan and the 2013 Stock Plan for the six months ended June 30, 2017 is as follows:

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In Years)		Aggregate Intrinsic Value
								(in thousands)
Outstanding as of December 31, 2016		1,267,329		$	16.22		6.6	$	8,355
Granted		—			—
Exercised		(239,836	)		9.12
Cancelled		(14,660	)		24.34
Outstanding as of June 30, 2017		1,012,833		$	17.79		6.2	$	22,795
Exercisable as of June 30, 2017		840,484		$	15.98		6.1	$	20,294

Recorded Stock-Based Compensation Expense in the Consolidated Statements of Operations and Comprehensive Loss

The Company recorded stock-based compensation expense in the statements of operations and comprehensive loss as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Cost of revenue	$	563	$	521	$	1,658	$	820
Selling and marketing		1,297		860		2,517		1,656
General and administrative		3,159		2,287		5,937		3,593
Research and development		1,707		963		3,013		1,601
Total	$	6,726	$	4,631	$	13,125	$	7,670

Weighted-Average Assumptions Used to Estimate Fair Value of Stock Options Using Black-Scholes Option Pricing Model

There were no stock options granted during the three and six months ended June 30, 2017 and three months ended June 30, 2016. The weighted-average assumptions used to estimate the fair value of stock options using the Black-Scholes option pricing model for the six months ended June 30, 2016 were as follows:

		Six Months Ended
	June 30, 2016
Expected volatility		59.2		%
Risk-free interest rate			1.9	%
Expected option term (in years)			6.25
Expected dividend yield			0.0	%