Stockholders' Equity - Common and Preferred Stock Dividends (Details) - $ / shares	3 Months Ended
Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019
Common stock
Class of Stock
Declaration Date	Jul. 31, 2020	Apr. 29, 2020	Feb. 20, 2020	Jul. 29, 2019	May 06, 2019	Feb. 25, 2019
Common Stock, Dividend Per Share	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.04	$ 0.04
Preferred Stock Series A
Class of Stock
Declaration Date	Jul. 31, 2020	Apr. 29, 2020	Feb. 20, 2020	Jul. 29, 2019	May 06, 2019	Feb. 25, 2019
Preferred Stock, Dividend Per Share	$ 0.46875	$ 0.46875	$ 0.46875	$ 0.46875	$ 0.46875	$ 0.46875
Preferred Stock Series B And Series C
Class of Stock
Declaration Date	Jul. 31, 2020	Apr. 29, 2020	Feb. 20, 2020	Jul. 29, 2019	May 06, 2019	Feb. 25, 2019
Preferred Stock, Dividend Per Share	$ 18.75	$ 18.75	$ 18.75	$ 18.75	$ 18.75	$ 18.75
Preferred Stock, Dividend Per Depositary Share	$ 0.46875	$ 0.46875		$ 0.46875	$ 0.46875	$ 0.46875
Preferred Stock Series D
Class of Stock
Declaration Date		Apr. 29, 2020			May 06, 2019
Preferred Stock, Dividend Per Share		$ 8,750.00			$ 8,750.00

Preferred Stock, Dividends, Per Depositary Share, Cash Paid

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