Weighted Average Shares

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Weighted Average Shares

Weighted Average Shares

Weighted-average shares were calculated as follows (in thousands):

	Year Ended December 31,
	2019	2018	2017
Basic weighted-average common shares outstanding	171,194	172,333	173,287
Effect of dilutive stock awards	4,075	5,073	6,264
Diluted weighted-average common and common-equivalent shares outstanding	175,269	177,406	179,551

Stock options to purchase 5,735,608, 2,650,164, and 3,363,141 shares of common stock, on a weighted-average basis, were outstanding in 2019, 2018, and 2017, respectively, but were not included in the calculation of dilutive net income per share because they were anti-dilutive. Restricted stock units totaling 13,092 shares of common stock, on

a weighted-average basis, were outstanding in 2019, but were not included in the calculation of dilutive net income per share because they were anti-dilutive. There were no restricted stock units outstanding that were anti-dilutive in 2018 or 2017.