Stock Option Plan (Tables)

12 Months Ended

Dec. 31, 2016

Transaction under Stock Option Plan

Transactions under the 2012 Plan for the years ending December 31, 2016, 2015, and 2014 were as follows:

(in thousands, except share and per share data)	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding, December 31, 2013		6,747,302		$	3.81
Granted		1,099,300			4.95
Exercised		(613,138	)		2.26
Cancelled		(727,801	)		4.54
Outstanding, December 31, 2014		6,505,663			4.07
Granted		427,800			10.47
Exercised		(3,249,160	)		3.95
Cancelled		(202,835	)		4.36
Outstanding, December 31, 2015		3,481,468			4.96
Granted		362,800			6.40
Exercised		(234,833	)		4.57
Cancelled		(144,100	)		6.43
Outstanding, December 31, 2016		3,465,335		$	5.07		6.58	$	3,407
Vested and unvested expected to vest at December 31, 2016		3,441,247		$	4.40		5.88	$	3,316
Options exercisable, December 31, 2016		2,671,835		$	4.40		5.88	$	3,383
Options exercisable, December 31, 2015		2,120,834		$	4.24		5.84	$	8,622
Options available for future grant		1,777,760

Summary of Non-Vested Restricted Stock

A summary of the status of non-vested restricted stock as of December 31, 2016, 2015 and 2014 is as follows:

	Number of Shares			Weighted-Average Grant Date Fair Value
Non-vested, December 31, 2013		352,865		$	4.38
Granted		66,828			5.07
Vested		(253,835	)		4.38
Cancelled		(21,350	)		4.41
Non-vested, December 31, 2014		144,508			4.70
Granted		1,590,574			9.01
Vested		(148,694	)		4.88
Cancelled		—			—
Non-vested, December 31, 2015		1,586,388			9.00
Granted		711,770			5.35
Vested		(617,666	)		8.90
Cancelled		—			—
Non-vested, December 31, 2016		1,680,492		$	5.54