Condensed Consolidated Statement of Shareholders' Equity (Parenthetical) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Dividends on common stock per share	$ 0.28	$ 0.24	$ 0.28	$ 0.24
8% Preferred Stock \| Preferred stock
Preferred stock, dividend rate (as a percent)	8.00%	8.00%	8.00%	8.00%
Dividends on preferred stock per share				$ 80.00
Final dividend for redemption of preferred stock per share				$ 3.33
7% Preferred Stock
Preferred stock, dividend rate (as a percent)			7.00%
7% Preferred Stock \| Preferred stock
Preferred stock, dividend rate (as a percent)	7.00%	7.00%	7.00%	7.00%
Dividends on preferred stock per share	$ 1.75	$ 1.75	$ 1.75	$ 1.75
6% Series B Preferred Stock
Preferred stock, dividend rate (as a percent)			6.00%
6% Series B Preferred Stock \| Preferred stock
Preferred stock, dividend rate (as a percent)	6.00%	6.00%	6.00%	6.00%
Dividends on preferred stock per share	$ 60.00	$ 60.00	$ 60.00	$ 60.00
6% Series C Preferred Stock
Preferred stock, dividend rate (as a percent)			6.00%
6% Series C Preferred Stock \| Preferred stock
Preferred stock, dividend rate (as a percent)	6.00%	6.00%	6.00%	6.00%
Dividends on preferred stock per share	$ 60.00	$ 60.00	$ 60.00	$ 60.00
Offering expenses on issuance of stock				$ 5,100,000
6% Series C Preferred Stock \| Private Placement \| Preferred stock
Preferred stock, dividend rate (as a percent)	6.00%	6.00%	6.00%	6.00%
Offering expenses on issuance of stock		$ 23,000		$ 23,000

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

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The cash outflow for cost incurred directly with the issuance of an equity security.

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-Publisher FASB
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The percentage rate used to calculate dividend payments on preferred stock.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Aggregate dividends declared during the period for each share of preferred stock outstanding.

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