Consolidated Statement of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Common stock dividends, share	$ 0.46	$ 0.42	$ 1.30	$ 1.26
Series A [Member]
Preferred stock dividends declared per share	894.444	894.444	2,654.166	2,663.888
Series B [Member]
Preferred stock dividends declared per share	223.611	223.61	663.542	665.97
Series F [Member]
Preferred stock dividends declared per share	406.25	406.25	1,218.75	1,218.75
Series H [Member]
Preferred stock dividends declared per share		321.88		965.64
Series I [Member]
Preferred stock dividends declared per share			232.953	640.625
Series J [Member]
Preferred stock dividends declared per share	662.50	662.50	1,325.00	1,325.00
Series K [Member]
Preferred stock dividends declared per share	343.75	$ 343.75	1,031.25	$ 1,031.25
Series L [Member]
Preferred stock dividends declared per share	234.375		703.125
Series M [Member]
Preferred stock dividends declared per share	$ 250.00		$ 702.778