Stock-based Compensation and Awards (Tables)

6 Months Ended

Jun. 30, 2012

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

Summary of the stock option activity

A summary of the stock option activity 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	(496,370	)	496,370		22.27
Options exercised	—		(350,750	)	1.36
Options canceled	26,989		(26,989	)	4.26
Options expired	4,961		(4,961	)	2.58
Early exercised options repurchased and added back to the pool	1,315		—
Outstanding at June 30, 2012	470,840		3,921,892		6.13	7.02	$	81,029

Summary of the restricted stock activty

A summary of the six month restricted stock activity 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
Granted	24,152	$	12.42	253,810		$	24.15
Vested	—	—		—
Forfeited	—	—		(500	)	$	24.15
Outstanding at June 30, 2012	24,152	$	12.42	253,310		$	24.15

Summary of assumptions used

The following assumptions were used for each respective period:

	Three months ended June 30,		Six months ended June 30,
	2012	2011	2012	2011
Expected Term (in years)	5.48	5.68	5.48 - 5.60	5.49 - 5.68
Volatility	48.7%	45%	47.9% - 48.7%	45%
Interest Rate	0.78%	2.20%	0.78% - 1.03%	2.20% - 2.48%
Dividend yield	0%	0%	0%	0%