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v3.20.1

Cumulative Preferred Stock (Characteristics of the First Preferred Shares) (Details) | 12 Months Ended
--- | ---
Dec. 31, 2019 $ / shares | Dec. 31, 2018 د.إ / shares
Series A Preferred Stock |  |
Class of Stock [Line Items] |  |
Initial Yield | 4.40% |
Current Annual Dividend | $ 0.6388 |
Earliest Redemption and/or Conversion Option Date | Aug. 15, 2020 |
Redemption Value | $ 25 |
Series A Preferred Stock | Minimum |  |
Class of Stock [Line Items] |  |
Initial Yield | 1.84% |
Series A Preferred Stock | Maximum |  |
Class of Stock [Line Items] |  |
Redemption Value | $ 25.5 |
Series C Preferred Stock |  |
Class of Stock [Line Items] |  |
Initial Yield | 4.10% |
Current Annual Dividend | (per share) | $ 1.1802 | د.إ 1.025
Earliest Redemption and/or Conversion Option Date | Aug. 15, 2023 |
Redemption Value | $ 25 |
Series C Preferred Stock | Minimum |  |
Class of Stock [Line Items] |  |
Initial Yield | 2.65% |
Series C Preferred Stock | Maximum |  |
Class of Stock [Line Items] |  |
Redemption Value | $ 25.5 |
Series F Preferred Stock |  |
Class of Stock [Line Items] |  |
Initial Yield | 4.25% |
Current Annual Dividend | $ 1.0625 |
Earliest Redemption and/or Conversion Option Date | Feb. 15, 2020 |
Redemption Value | $ 25 |
Series F Preferred Stock | Minimum |  |
Class of Stock [Line Items] |  |
Initial Yield | 2.63% |
Series F Preferred Stock | Maximum |  |
Class of Stock [Line Items] |  |
Redemption Value | $ 25.5 |
Series B Preferred Stock |  |
Class of Stock [Line Items] |  |
Initial Yield | 2.393% |
Earliest Redemption and/or Conversion Option Date | Aug. 15, 2020 |
Redemption Value | $ 25 |
Series B Preferred Stock | Minimum |  |
Class of Stock [Line Items] |  |
Initial Yield | 1.84% |
Series H Preferred Stock |  |
Class of Stock [Line Items] |  |
Initial Yield | 4.90% |
Current Annual Dividend | $ 1.225 |
Earliest Redemption and/or Conversion Option Date | Aug. 15, 2023 |
Redemption Value | $ 25 |
Series H Preferred Stock | Minimum |  |
Class of Stock [Line Items] |  |
Initial Yield | 4.90% |
Series H Preferred Stock | Maximum |  |
Class of Stock [Line Items] |  |
Redemption Value | $ 25.5 |
Series I Preferred Stock | Minimum |  |
Class of Stock [Line Items] |  |
Initial Yield | 2.54% |
Perpetual fixed rate Series E Preferred Stock |  |
Class of Stock [Line Items] |  |
Initial Yield | 4.50% |
Current Annual Dividend | $ 1.125 |
Redemption Value | $ 25.75 |

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