Consolidated Statements of Equity (Parentheticals) - $ / shares  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2021  | 
Dec. 31, 2020  | 
Dec. 31, 2019  | 
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| Consolidated Statements of Equity | |||
| Dividends to common stockholders | $ 0.82 | $ 0.80 | $ 0.80 | 
| Dividends to preferred stockholders | $ 1.875 | $ 1.875 | $ 1.875 | 
| X | ||||||||||
- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
- Definition Aggregate dividends declared during the period for each share of preferred stock outstanding. No definition available. 
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| X | ||||||||||
- References No definition available. 
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