Net Income Per Share (Tables)

3 Months Ended

Mar. 31, 2018

Earnings Per Share [Abstract]

Reconciliation between Basic and Diluted Weighted Average Shares Outstanding

	Three months ended   March 31,
(in thousands, except per share data)	2018			2017
Net income	$	90,828		$	70,110
Net income attributable to unvested awarded performance stock	(1,902		)	(1,686		)
Net income attributable to common shares	$	88,926		$	68,424
Weighted average number of common shares outstanding – basic	275,952			280,224
Less unvested awarded performance stock included in weighted average number of common shares outstanding – basic	(5,780		)	(6,737		)
Weighted average number of common shares outstanding for basic net income per common share	270,172			273,487
Dilutive effect of stock options	5,542			4,565
Weighted average number of shares outstanding – diluted	275,714			278,052
Net income per share:
Basic	$	0.33		$	0.25
Diluted	$	0.32		$	0.25