Stock options, restricted stock and performance stock options (Tables)

6 Months Ended

Jun. 30, 2015

Stock options, restricted stock and performance stock options

Schedule of weighted-average key assumptions used in determining fair value of options granted

	Three Months			Six Months
	Ended June 30,			Ended June 30,
	2015			2015
Estimated dividend yield	0		%	0		%
Expected stock price volatility	60		%	60		%
Weighted-average risk-free interest rate	1.70		%	1.67		%
Expected life of option in years	5			5
Weighted-average option fair value at grant	$	5.568		$	5.235

Summary of outstanding and exercisable options

			Weighted-
	Number of		Average		Intrinsic
	Options		Exercise Price		Value
					(in thousands)
Outstanding at December 31, 2014	511,775		$	3.684	$	2,883
Exercisable at December 31, 2014	150,109		$	1.467	$	1,179
Granted	271,661		10.096
Exercised	(4,443	)	0.877
Expired, forfeited or cancelled	(2,083	)	3.689
Outstanding at June 30, 2015	776,910		$	5.942	$	5,359
Exercisable at June 30, 2015	177,200		$	1.716	$	1,971