Shareholders' Equity (Tables)

12 Months Ended

Dec. 31, 2015

Stockholders' Equity

Summary of stock option under all equity incentive plans

	Number of Shares			Weighted Average Exercise Price
Options outstanding as of December 31, 2012		2,905,761		$	6.44
Granted		729,439		$	3.24
Cancelled		(393,770	)	$	5.93
Exercised		(105,496	)	$	4.43
Options outstanding as of December 31, 2013		3,135,934		$	5.83
Granted		582,012		$	8.45
Cancelled		(310,303	)	$	6.55
Exercised		(156,791	)	$	3.37
Options outstanding as of December 31, 2014		3,250,852		$	6.40
Granted		427,786		$	10.39
Cancelled		(181,777	)	$	11.32
Exercised		(76,342	)	$	3.82
Options outstanding as of December 31, 2015		3,420,519		$	6.69

Summary of total outstanding stock options

        A summary of total outstanding stock options as of December 31, 2015 is as follows:

	Options Outstanding						Options Exercisable
Range of Exercise Price	Number Outstanding		Weighted Average Remaining Contractual Life (in years)		Weighted Average Exercise Price		Number Exercisable		Weighted Average Remaining Contractual Life (in years)		Weighted Average Exercise Price
$0.70 - $7.50		2,325,971		5.80	$	4.09		2,056,224		5.61	$	4.15
$7.51 - $15.00		845,824		8.55	$	9.62		277,656		7.99	$	9.34
$15.01 - $22.50		190,824		3.29	$	18.38		190,824		3.29	$	18.38
$22.51 - $31.18		57,900		2.61	$	29.83		57,900		2.61	$	29.83
$0.70 - $31.18		3,420,519		6.29	$	6.69		2,582,604		5.63	$	6.34

Summary of certain additional information with respect to options

(In thousands)	2015		2014		2013
Aggregate intrinsic value of options outstanding at year-end	$	19,436	$	15,258	$	11,183
Aggregate intrinsic value of options exercisable at year-end		16,124		9,918		4,382
Aggregate intrinsic value of options exercised during the year		662		840		422

Summary of Restricted stock units activity

	Number of Shares			Weighted Average Grant Date Fair Value
Restricted stock outstanding as of December 31, 2012		763,342		$	3.54
Granted		457,200		$	3.52
Forfeited		(82,813	)	$	3.07
Vested		(280,073	)	$	4.82
Restricted stock outstanding as of December 31, 2013		857,656		$	3.15
Granted		292,079		$	8.48
Forfeited		(89,664	)	$	3.30
Vested		(195,437	)	$	6.27
Restricted stock outstanding as of December 31, 2014		864,634		$	4.23
Granted		328,060		$	9.70
Forfeited		(50,642	)	$	6.90
Vested		(451,116	)	$	3.89
Restricted stock outstanding as of December 31, 2015		690,936		$	6.85

Summary of total outstanding RSUs

        In addition, a summary of total outstanding RSUs as of December 31, 2015 is as follows:

Range of Grant Price	RSUs Outstanding
$2.16 - $6.75		255,564
$6.76 - $9.75		435,372
$2.16 - $9.75		690,936

Summary of Performance stock units activity

	Number of Shares			Weighted Average Grant Date Fair Value
Performance stock outstanding as of December 31, 2013		—			—
Granted		284,423		$	8.68
Forfeited		—			—
Vested		—			—
Performance stock outstanding as of December 31, 2014		284,423		$	8.68
Granted		—			—
Forfeited		(18,433	)	$	8.68
Vested		—			—
Performance stock outstanding as of December 31, 2015		265,990		$	8.68

Schedule of weighted average assumptions used to estimate the fair value of the stock-based awards

	Year Ended December 31,
	2015			2014			2013
Expected volatility		66.5	%		62.8	%		60.3	%
Expected term (in years)		6.72			6.49			6.71
Weighted average risk-free interest rate		1.68	%		1.85	%		1.34	%
Expected dividends		0.0	%		0.0	%		0.0	%
Weighted average grant date fair value per option	$	6.58		$	5.00		$	1.90
Weighted average grant date fair value per RSU	$	9.71		$	8.43		$	3.52