Consolidated Statement of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Common stock dividends, share	$ 0.42	$ 0.42
Series A [Member]
Preferred stock dividends declared per share	875.00	884.722
Series B [Member]
Preferred stock dividends declared per share	218.75	221.18
Series F [Member]
Preferred stock dividends declared per share	406.25	406.25
Series H [Member]
Preferred stock dividends declared per share		321.88
Series I [Member]
Preferred stock dividends declared per share	232.953
Series J [Member]
Preferred stock dividends declared per share	662.50	662.50
Series K [Member]
Preferred stock dividends declared per share	343.75	$ 343.75
Series L [Member]
Preferred stock dividends declared per share	234.375
Series M [Member]
Preferred stock dividends declared per share	$ 202.778