Earnings per Share

12 Months Ended

Dec. 31, 2015

Earnings per Share

Earnings per Share

11. Earnings per Share

Basic income (loss) per common share is determined by dividing income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted income (loss) per share is computed by dividing the income (loss) 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, SAR, and potential Employee Stock Purchase Plan (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 loss per share because their effect would be anti-dilutive as applied to the loss from continuing operations applicable to common stockholders for the years ended December 31, 2015, 2014, and 2013:

	Year Ended December 31,
	2015		2014		2013
Shares underlying Convertible Senior Secured Notes		—		—		6,219,782
Warrants to purchase common stock		—		—		13,388
Stock options, stock appreciation rights, non-vested stock options and ESPP awards		—		—		151,737

The following table sets forth the computation of basic and diluted net income per share for the years ended December 31, 2015, 2014, and 2013, in thousands, except share and per share amounts:

	Year ended December 31,
	2015			2014			2013
Numerator, in thousands:
Net income (loss) used for calculation of basic EPS	$	14,016		$	19,871		$	(92,273	)
Interest expense on convertible debt		1,229			4,963			—
Changes in fair value of derivative liabilities		(589	)		(2,809	)		—
Loss on extinguishment of debt		2,338			2,592			—
Loss on extinguishment of outstanding debt, as if converted		(2,494	)		(8,315	)		—
Total adjustments		484			(3,569	)		—
Net income used for calculation of diluted EPS	$	14,500		$	16,302		$	(92,273	)
Denominator:
Weighted average shares outstanding, basic		47,485,258			42,260,896			31,848,299
Effect of dilutive potential common shares:								—
Shares underlying Convertible Senior Secured Notes		2,459,009			7,090,722
Shares issuable to settle interest make-whole derivatives		804,507			904,618			—
Warrants to purchase common stock		—			20,499			—
Stock options, stock appreciation rights, and non-vested stock options		411,606			306,776			—
Total potential dilutive common shares		3,675,122			8,322,615			—
Weighted average shares outstanding, diluted		51,160,380			50,583,511			31,848,299
Net income (loss) per share, basic	$	0.30		$	0.47		$	(2.90	)
Net income (loss) per share, diluted	$	0.28		$	0.32		$	(2.90	)