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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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