CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (unaudited) (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Common stock, per share (in dollars per share)	$ 0.30	$ 0.27	$ 0.84	$ 0.81
Series H Preferred Stock
Preferred stock, per share (in dollars per share)			637.50	637.50
Series I Preferred Stock
Preferred stock, per share (in dollars per share)	414.06	414.06	1,242.18	1,242.18
Series J Preferred Stock
Preferred stock, per share (in dollars per share)	209.30	219.65	631.24	829.58
Series K Preferred Stock
Preferred stock, per share (in dollars per share)	309.38	309.38	928.13	928.14
Series L Preferred Stock
Preferred stock, per share (in dollars per share)	281.25	187.50	843.75	187.50
Class B, Series A Preferred Stock
Preferred stock, per share (in dollars per share)	$ 15.00	$ 15.00	$ 45.00	$ 45.00