Stock Option Plan (Tables)

6 Months Ended

Jun. 30, 2013

Stock Option Plan

Summary of stock option activity

	Options		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value
Outstanding at December 31, 2012	1,819,839		$	2.76
Options granted	141,500		18.96
Options exercised	(23,038	)	2.50
Options forfeited	(58,728	)	3.24
Outstanding at June 30, 2013	1,879,573		$	3.97	6.24	$	37,426,040
Options exercisable at June 30, 2013	1,322,795		$	2.96	5.16	$	27,616,536

Summary of restricted stock activity

	Restricted Stock	Aggregate Intrinsic Value
Outstanding at December 31, 2012	34,507
Shares granted	231,614
Shares forfeited	—
Outstanding at June 30, 2013	266,121	$	6,344,325
Vested shares at June 30, 2013	17,252	$	411,288