Quarterly Results of Operations (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information

The following is a summary of the unaudited quarterly results of operations for the years ended December 31, 2019 and 2018:

	Quarter Ended
($ in thousands except per share data)	December 31, 2019		September 30, 2019		June 30, 2019		March 31, 2019
Revenues	$	237,537	$	222,513	$	220,746	$	214,002
Operating income	226,758		208,380		205,495		201,866
Net income	100,713		146,515		154,127		152,926
Net income attributable to common stockholders	98,631		144,435		152,049		150,849
Net income per common share
Basic and Diluted	$	0.21	$	0.31	$	0.37	$	0.37
Dividends per share	$	0.2975	$	0.2975	$	0.2875	$	0.2875

	Quarter Ended
($ in thousands except per share data)	December 31, 2018		September 30, 2018		June 30, 2018		March 31, 2018
Revenues	$	226,039	$	232,687	$	220,975	$	218,276
Operating income	195,682		184,100		189,448		188,724
Net income	144,631		132,024		141,359		114,103
Net income attributable to common stockholders	142,541		129,912		139,044		112,122
Net income per common share
Basic and diluted	$	0.37	$	0.35	$	0.38	$	0.33
Dividends per share	$	0.2875	$	0.2875	$	0.2625	$	0.1600