Consolidated Statements of Stockholders' Equity (Unaudited) (Parentheticals) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Preferred stock dividends declared, per share (in dollars per share)	$ 0.5313	$ 0.5313	$ 1.5938	$ 0.5313
Common stock dividends declared, per share (in dollars per share)	$ 0.4750	$ 0.4000	$ 1.4250	$ 1.0198