Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Reconciliation between Basic and Diluted Weighted Average Shares Outstanding

The following is a reconciliation between basic and diluted weighted average shares outstanding for the years ended December 31:

(in thousands, except per share data)	2020			2019			2018
Net income	$	480,483		$	398,514		$	344,255
Net income attributable to unvested awarded performance stock		(15,197	)		(12,873	)		(8,297	)
Net income attributable to common shares	$	465,286		$	385,641		$	335,958
Weighted average number of common shares outstanding – basic		283,294			281,566			277,663
Less unvested awarded performance stock included in weighted average number of common shares outstanding – basic		(8,960	)		(9,095	)		(6,692	)
Weighted average number of common shares outstanding for basic earnings per common share		274,334			272,471			270,971
Dilutive effect of stock options		1,533			2,145			4,550
Weighted average number of shares outstanding – diluted		275,867			274,616			275,521
Net income per share:
Basic	$	1.70		$	1.42		$	1.24
Diluted	$	1.69		$	1.40		$	1.22