Earnings Per Share

Basic earnings per share is computed by dividing net income by the weighted average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income by the weighted average number of common shares outstanding plus the effect of dilutive potential common shares outstanding during the period using the treasury stock method. Dilutive potential common shares include outstanding stock options and restricted stock awards. There are no differences in the numerators of our computations of basic and diluted earnings per share for any period presented. The computation of basic and diluted earnings per share is shown below (in thousands, except per share amounts).



	Three Months Ended June 30,				Six Months Ended June 30,
	2018		2017		2018		2017
Net income	$	38,264	$	23,219	$	66,071	$	39,238
Weighted average common shares outstanding	72,144		72,227		72,289		72,209
Dilutive effect of stock-based awards	232		265		233		260
Shares used in computing diluted earnings per share	72,376		72,492		72,522		72,469
Basic earnings per share	$	0.53	$	0.32	$	0.91	$	0.54
Diluted earnings per share	$	0.53	$	0.32	$	0.91	$	0.54

There were no options to purchase shares of common stock that were outstanding during the periods indicated above that were excluded from the computation of diluted earnings per share because the option purchase price was greater than the average market price of the common shares during the period. Performance awards are excluded from the calculation of dilutive potential common shares until the threshold performance conditions have been satisfied.