Consolidated Statements of Equity (Parenthetical)	12 Months Ended
	Dec. 31, 2020 $ / shares	Dec. 31, 2019 $ / shares		Dec. 31, 2018 $ / shares
Dividends paid per common share (in usd per share)	$ 0.300	$ 0.900	[1]	$ 1.500	[1]
Series A Preferred Stock
Preferred dividends, per share amount (in usd per share)	1.719	1.375		1.375
Series L Preferred Stock
Preferred dividends, per share amount (in usd per share)	1.560	1.560		$ 1.738
Series D Preferred Stock
Preferred dividends, per share amount (in usd per share)	$ 1.648
Special Dividend
Dividends paid per common share (in usd per share)		$ 42.000

[1] All share and per share amounts have been adjusted to give retroactive effect to the one-for-three reverse stock split of our common stock effected on September 3, 2019.