CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Unaudited) (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Common Stock, Dividends, Per Share, Declared	$ 0.215	$ 0.185	$ 0.430	$ 0.370
5.875% Series A Cumulative Redeemable Preferred Stock
Preferred Stock, Dividend Rate, Percentage			5.875%		5.875%
Preferred Stock, Dividends Per Share, Declared	0.367188	0.367188	$ 0.734376	0.734376
5.875% Series B Cumulative Redeemable Preferred Stock
Preferred Stock, Dividend Rate, Percentage			5.875%		5.875%
Preferred Stock, Dividends Per Share, Declared	0.367188	$ 0.367188	$ 0.734376	$ 0.734376
5.625% Series C Cumulative Redeemable Preferred Stock
Preferred Stock, Dividend Rate, Percentage			5.625%		5.625%
Preferred Stock, Dividends Per Share, Declared	$ 0.351563		$ 0.703126
4.00% Cumulative Redeemable Convertible Preferred Units
Preferred Stock, Dividend Rate, Percentage			4.00%
4.43937% Cumulative Redeemable Convertible Preferred Units
Preferred Stock, Dividend Rate, Percentage		4.43937%		4.43937%