Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2013

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Weighted Average Black-Scholes Model Assumptions

The weighted average Black-Scholes model assumptions for the three and nine months ended September 30, 2013 and 2012 were as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
Expected term (in years)	5.0		5.0		5.0		5.1
Expected volatility	43	%	46	%	44	%	46	%
Risk-free interest rate	1.48	%	0.67	%	0.95	%	0.78	%
Expected dividend yield	—		—		—		—

Reconciliation of Option and Restricted Stock Activity

Option and restricted stock activity under the 2011 Plan for the nine months ended September 30, 2013 was as follows (shares in thousands)

			Options Outstanding				Restricted Stock Outstanding
	Shares and Units Available for Grant		Number of Shares		Weighted- Average Exercise Price		Number of Shares
Outstanding — December 31, 2012	4,024		15,189		$	6.98	3,928
Additional shares reserved under the 2011 equity incentive plan	3,025		—		—		—
Granted	(4,746	)	2,304		7.00		2,442
Options exercised/ Restricted stock released	—		(4,494	)	4.45		(558	)
Canceled/Forfeited	5,000		(4,053	)	10.47		(947	)
Outstanding — September 30, 2013	7,303		8,946		5.57		4,865

Summary of Stock-Based Compensation Expense

The following table summarizes the consolidated stock-based compensation expense included in the condensed consolidated statements of operations (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
Cost of revenue	$	802	$	763	$	2,222	$	2,050
Sales and marketing	2,414		2,180		7,396		5,836
Research and development	753		562		1,758		1,455
General and administrative	1,989		2,148		5,925		5,919
Total stock-based compensation	$	5,958	$	5,653	$	17,301	$	15,260