Stock-based Compensation and Awards (Tables)

9 Months Ended

Sep. 30, 2012

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

Summary of the stock option activity

A summary of the stock option activity for the nine months ended September 30, 2012 is presented below:

	Shares Available for Grant		Number of Options		Weighted Average Exercise Price		Weighted average remaining contractual term	Aggregate intrinsic value
							(in years)	(in thousands)
Outstanding at December 31, 2011	1,101,111		3,808,222		$	3.57	6.68	$	28,682
Shares removed from the plan	(167,166	)	—
Options granted	(534,870	)	534,870		$	22.81
Options exercised	—		(731,602	)	$	2.03
Options canceled	38,658		(38,658	)	$	5.35
Options expired	5,399		(5,399	)	$	2.68
Early exercised options repurchased and added back to the pool	1,454		—
Outstanding at September 30, 2012	444,586		3,567,433		$	6.75	6.68	$	86,181

Summary of the restricted stock activty

A summary of restricted stock activity for the nine months ended September 30, 2012 is presented below:

	Restricted Stock Awards			Restricted Stock Units
	Number of shares	Weighted Average Grant Date Fair Value per Share		Number of shares		Weighted Average Grant Date Fair Value per Share
Outstanding at December 31, 2011	—	—		—		—
Granted	24,152	$	12.42	300,660		$	25.12
Vested	—	—		—		—
Forfeited	—	—		(2,200	)	$	24.15
Outstanding at September 30, 2012	24,152	$	12.42	298,460		$	25.13

Summary of assumptions used

The following assumptions were used for each respective period:

	Three months ended September 30,		Nine months ended September 30,
	2012	2011	2,012	2,011
Expected Term (in years)	5.48	5.77	5.48 - 5.60	5.49 - 5.72
Volatility	48.0%	44.7%	47.9% - 48.7%	44.7% - 45.0%
Interest Rate	0.72%	1.73%	0.72% - 1.03%	1.73% - 2.48%
Dividend yield	0%	0%	0%	0%