Earnings Per Share

12 Months Ended

Dec. 31, 2015

Basic earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of common shares outstanding. Diluted earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of common shares plus the effect of dilutive potential common shares outstanding during the period. The diluted earnings per share for the year ended December 31, 2013 excludes the impact of approximately 0.3 million common stock equivalents, since the effect of including these securities would be anti-dilutive. The following table sets forth the computation of basic and diluted earnings per share (shares in thousands):



	Year Ended December 31,
	2015		2014		2013
Numerator:
Net income available to common stockholders	$	585	$	540	$	387
Denominator:
Denominator for basic earnings per share—weighted-average common shares	95,170		97,489		93,436
Effect of dilutive securities:
Employee stock options and warrants	300		394		504
4 percent Convertible Senior Notes	660		6,386		11,769
Restricted stock units	249		687		582
Denominator for diluted earnings per share—adjusted weighted-average common shares	96,379		104,956		106,291
Basic earnings per share	$	6.14	$	5.54	$	4.14
Diluted earnings per share	$	6.07	$	5.15	$	3.64