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				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
	(In thousands, except per share amounts)
Amounts attributable to common stockholders:
Net income:
Net income — basic	$	68,935	$	56,164	$	254,162	$	299,347
After tax interest on convertible debt	15		13		45		38
Net income — diluted	$	68,950	$	56,177	$	254,207	$	299,385
Weighted average shares (denominator):
Weighted average shares — basic	180,858		187,435		182,859		187,761
Stock options	4,284		4,575		4,364		4,448
Restricted stock units	197		112		173		87
Convertible debt	121		121		121		121
Weighted average shares — diluted	185,460		192,243		187,517		192,417
Net income per share:
Basic	$	0.38	$	0.30	$	1.39	$	1.59
Diluted	$	0.37	$	0.29	$	1.36	$	1.56

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		Nine Months Ended
	September 30,		September 30,
	2018	2017	2018	2017
	(In thousands)		(In thousands)
Anti-dilutive options	831	—	980	878