Earnings per Share

12 Months Ended

Dec. 31, 2015

5. EARNINGS PER SHARE

Earnings per share is computed as follows (in thousands, except per share data):

	Year Ended December 31,
	2015						2014						2013
	Net Income		Shares		Per Share Amount		Net Income		Shares		Per Share Amount		Net Income		Shares		Per Share Amount
Basic earnings per share	$	49,133		85,860	$	0.57	$	49,919		87,183	$	0.57	$	51,920		87,537	$	0.59
Effect of dilutive incentive-based awards				121						297						615
Diluted earnings per share	$	49,133		85,981	$	0.57	$	49,919		87,480	$	0.57	$	51,920		88,152	$	0.59

In accordance with the Earnings Per Share Topic of the ASC, basic earnings per share is computed by dividing net income by the weighted average number of shares of common stock outstanding during the period (excluding treasury stock and unvested restricted stock). The shares of unvested restricted stock are eligible to receive dividends; however, dividend rights will be forfeited if the award does not vest. Accordingly, only vested shares of outstanding restricted stock are included in the calculation of basic earnings per share. The weighted average number of repurchased shares during the period, if any, which are held as treasury stock are excluded from common stock outstanding.

Diluted earnings per share is determined using the treasury stock method based on the dilutive effect of unvested restricted stock and certain shares of common stock that are issuable upon exercise of stock options. During the year ended December 31, 2015, there were approximately 1,879,000 antidilutive shares of common stock excluded from the computation of diluted earnings per share. During the year ended December 31, 2014, there were approximately 21,000 antidilutive shares of common stock excluded from the computation of diluted earnings per share. During the year ended December 31, 2013, there were no antidilutive shares of common stock excluded from the computation of diluted earnings per share.

The Company’s outstanding performance-vesting restricted share awards are considered contingently issuable shares and are excluded from the calculation of diluted earnings per share until the performance measure criteria is met as of the end of the reporting period. For the year ended December 31, 2015, approximately 19,000 performance-vesting restricted share awards were included in the calculation of diluted earnings per share as their respective performance criteria was met as of December 31, 2015. There were no performance-vesting restricted share awards included in the calculation of diluted earnings per share during the years ended December 31, 2014 and 2013. See further discussion in Note 18–Equity-Based Compensation.