10. Earnings Per Share

Basic earnings per common share (EPS) excludes dilution and is computed by dividing Net income attributable to common stockholders by the weighted average number of common shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur if securities or other obligations to issue common stock were exercised or converted into common stock or resulted in the issuance of common shares that then shared in our earnings.

A reconciliation of the numerators and denominators of the basic and diluted EPS computations is presented below:



	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
	(In thousands, except per share amounts)
Amounts attributable to common stockholders:
Net income:
Net income — basic	$	103,239	$	68,481	$	185,227	$	243,183
After tax interest on convertible debt	15		13		30		25
Net income — diluted	$	103,254	$	68,494	$	185,257	$	243,208
Weighted average shares (denominator):
Weighted average shares — basic	182,637		187,597		183,877		187,927
Stock options	4,265		4,333		4,391		4,389
Restricted stock units	165		87		158		74
Convertible debt	121		121		121		121
Weighted average shares — diluted	187,188		192,138		188,547		192,511
Net income per share:
Basic	$	0.57	$	0.37	$	1.01	$	1.29
Diluted	$	0.55	$	0.36	$	0.98	$	1.26

The computation of diluted EPS excludes outstanding stock options in certain periods in which the inclusion of such options would be anti-dilutive in the periods presented. Total options not included in the computation of dilutive EPS are as follows (in shares):



	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2018	2017	2018	2017
	(In thousands)		(In thousands)
Antidilutive options	1,155	1,523	868	1,212