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Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended						12 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2020
Common stock dividends per share, declared	$ 0.27	$ 0.27	$ 0.27	$ 0.26	$ 0.26	$ 0.26
Series A 3% Preferred Stock [Member]
Preferred stock, dividend percentage	3.00%	3.00%	3.00%	3.00%	3.00%	3.00%	3.00%
Preferred stock dividends per share, declared	$ 0.75	$ 0.75	$ 0.75	$ 0.75	$ 0.75	$ 0.75
Series B-1 8.48% Preferred Stock [Member]
Preferred stock, dividend percentage	8.48%	8.48%	8.48%	8.48%	8.48%	8.48%	8.48%
Preferred stock dividends per share, declared	$ 2.12	$ 2.12	$ 2.12	$ 2.12	$ 2.12	$ 2.12

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- Definition

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

+ References

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-Publisher FASB
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-Topic 505
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- Definition

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

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-Publisher FASB
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