CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (unaudited) (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Common stock, per share (in dollars per share)	$ 0.27	$ 0.27	$ 0.54	$ 0.54
Series H Preferred Stock
Preferred stock, per share (in dollars per share)	637.50	637.50	637.50	637.50
Series I Preferred Stock
Preferred stock, per share (in dollars per share)	414.06	414.06	828.12	828.12
Series J Preferred Stock
Preferred stock, per share (in dollars per share)	210.44	289.38	421.94	609.93
Series K Preferred Stock
Preferred stock, per share (in dollars per share)	309.38	309.38	618.75	618.76
Series L Preferred Stock
Preferred stock, per share (in dollars per share)	281.25		562.50
Class B Preferred stock, Series A
Preferred stock, per share (in dollars per share)	$ 15.00	$ 15.00	$ 30.00	$ 30.00