Earnings Per Share of Common Stock (Tables)

6 Months Ended

Jun. 30, 2020

Earnings Per Share of Common Stock

Summary of basic and diluted earnings per share calculations

	Quarter ended June 30,				Six months ended June 30,
	2020		2019		2020		2019
	(in thousands, except per share amounts)
Net income	$	352,677	$	72,696	$	658,920	$	118,831
Weighted average basic shares of common stock outstanding		77,790		78,335		78,240		77,996
Effect of dilutive shares:
Common shares issuable under stock-based compensation plan		2,634		983		3,001		1,305
Weighted average shares of common stock applicable to diluted earnings per share		80,424		79,318		81,241		79,301
Basic earnings per share of common stock	$	4.53	$	0.93	$	8.42	$	1.52
Diluted earnings per share of common stock	$	4.39	$	0.92	$	8.11	$	1.50

Schedule of anti-dilutive shares outstanding

	Quarter ended June 30,				Six months ended June 30,
	2020		2019		2020		2019
	(in thousands except for weighted-average exercise price)
Performance-based RSUs (1)		422		1,811		292		1,547
Time-based RSUs		79		—		110		1
Stock options (2)		273		982		189		845
Total anti-dilutive shares and units		774		2,793		591		2,393
Weighted average exercise price of anti-dilutive stock options (2)	$	35.03	$	18.34	$	35.03	$	18.34

(1) Certain performance-based RSUs were outstanding but not included in the computation of earnings per share because the performance thresholds included in such RSUs have not been achieved.

(2) Certain stock options were outstanding but not included in the computation of diluted earnings per share because the weighted-average exercise prices were above the average stock prices for the period.