Earnings Per Share

Basic earnings per share is computed based on income available to common stockholders and the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share is computed based on income available to common stockholders and the weighted-average number of shares of common stock outstanding plus the effect of potentially dilutive common shares outstanding during the period using the treasury stock method, which includes stock options and restricted stock units ("RSUs"). Potential common shares, composed of the incremental common shares issuable upon the exercise of outstanding stock options and nonvested RSUs, are included in the diluted earnings per share calculation to the extent that they are dilutive. In loss periods, the assumed exercise of in-the-money stock options and restricted stock units has an anti-dilutive effect, and therefore these instruments are excluded from the computation of diluted earnings per share.

The following table sets forth the computation of basic and diluted earnings per share:



	Three Months Ended September 30,				Six Months Ended September 30,
(In thousands, except per share data)	2018		2017		2018		2017
Numerator
Net income	$	30,841	$	30,705	$	65,307	$	64,464

Denominator
Denominator for basic earnings per share — weighted average shares outstanding	51,841		53,098		52,238		53,068
Dilutive effect of nonvested restricted stock units and options issued to employees and directors	312		441		307		456
Denominator for diluted earnings per share	52,153		53,539		52,545		53,524

Earnings per Common Share:
Basic earnings per share	$	0.59	$	0.58	$	1.25	$	1.21

Diluted earnings per share	$	0.59	$	0.57	$	1.24	$	1.20

For the three months ended September 30, 2018 and 2017, there were 0.7 million and 0.4 million shares, respectively, attributable to outstanding stock-based awards that were excluded from the calculation of diluted earnings per share because their inclusion would have been anti-dilutive. For the six months ended September 30, 2018 and 2017, there were 0.5 million and 0.4 million shares, respectively, attributable to outstanding stock-based awards that were excluded from the calculation of diluted earnings per share because their inclusion would have been anti-dilutive.