Earnings per Share

6 Months Ended

Jun. 30, 2016

Earnings per Share

Earnings per Share

11.  Earnings per Share

Basic income per common share is determined by dividing income attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted income per share is computed by dividing the income attributable to common stockholders by the weighted-average number of common share equivalents outstanding for the period. The treasury stock method is used to determine the dilutive effect of the Company’s stock option grants, SARs, and potential ESPP awards, and the if-converted method is used to determine the dilutive effect of the Company’s Notes.

The following common stock equivalents were excluded in the calculation of diluted income per share because their effect would be anti-dilutive as applied to the income from continuing operations applicable to common stockholders for the three and six months ended June 30, 2016 and 2015:

	Three Months ended June 30,		Six Months ended June 30,
	2016	2015	2016	2015
	(unaudited)		(unaudited)
Shares underlying Convertible Senior Secured Notes	—	—	—	2,791,624
Warrants to purchase common stock	—	28,613	—	25,950
Stock options, stock appreciation rights, and non-vested stock options	1,124,100	—	1,159,100	—

The following table sets forth the computation of basic and diluted net income per share for the three and six months ended June 30, 2016 and 2015, in thousands, except share and per share amounts:

	Three Months ended June 30,						Six Months ended June 30,
	2016			2015			2016			2015
	(unaudited)						(unaudited)
Numerator, in thousands:
Net income used for calculation of basic EPS	$	10,018		$	2,005		$	15,005		$	2,923
Interest expense on convertible debt	196			331			375			—
Changes in fair value of derivative liabilities	(123		)	(195		)	(224		)	—
Loss on extinguishment of debt	—			241			382			—
Loss on extinguishment of outstanding debt, as if converted	(849		)	(553		)	(1,183		)	—
Total adjustments	(776		)	(176		)	(650		)	—
Net income used for calculation of diluted EPS	$	9,242		$	1,829		$	14,355		$	2,923
Denominator:
Weighted average shares outstanding, basic	49,427,825			47,911,932			49,333,962			46,246,866
Effect of dilutive potential common shares:
Shares underlying Convertible Senior Secured Notes	1,240,814			2,417,586			1,301,885			—
Shares issuable to settle interest make-whole derivatives	52,563			246,105			71,537			—
Stock options, stock appreciation rights, and non-vested stock options	1,024,140			1,697,926			777,302			1,441,126
Total potential dilutive common shares	2,317,517			4,361,617			2,150,724			1,441,126
Weighted average shares outstanding, diluted	51,745,342			52,273,549			51,484,686			47,687,992
Net income per share, basic	$	0.20		$	0.04		$	0.30		$	0.06
Net income per share, diluted	$	0.18		$	0.03		$	0.28		$	0.06