Stockholders' Equity - Dividends Declared (Details) - $ / shares	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Common stock
Class of Stock
Declaration Date	Feb. 20, 2020	Feb. 25, 2019
Common Stock, Dividend Per Share	$ 0.05	$ 0.04
Preferred Stock Series A
Class of Stock
Declaration Date	Feb. 20, 2020	Feb. 25, 2019
Preferred Stock, Dividend Per Share	$ 0.46875	$ 0.46875
Preferred Stock Series B
Class of Stock
Declaration Date	Feb. 20, 2020	Feb. 25, 2019
Preferred Stock, Dividend Per Share	$ 18.75	$ 18.75
Preferred Stock, Dividend Per Depositary Share	$ 0.46875	$ 0.46875
Preferred Stock Series C
Class of Stock
Declaration Date	Feb. 20, 2020	Feb. 25, 2019
Preferred Stock, Dividend Per Share	$ 18.75	$ 18.75
Preferred Stock, Dividend Per Depositary Share	$ 0.46875	$ 0.46875

Preferred Stock, Dividends, Per Depositary Share, Cash Paid

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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Aggregate dividends paid during the period for each share of preferred stock outstanding.

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