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Equity and Mezzanine Equity - Dividends Declared (Detail) - $ / shares | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Senior Common Stock |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, cash paid (in dollars per share) | $ 1.0500 | $ 1.0500 | $ 1.0500
Series A Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, cash paid (in dollars per share) | 0 | 1.6038191 | 1.9374996
Series B Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, cash paid (in dollars per share) | 0 | 1.5521 | 1.8750
Series D Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, cash paid (in dollars per share) | 1.7500 | 1.7500 | 1.7500
Series E Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, cash paid (in dollars per share) | 1.656252 | 0.404900 | 0
Series F Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, cash paid (in dollars per share) | 0.7500 | 0 | 0
Common Stock and Non-controlling OP Units |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, cash paid (in dollars per share) | $ 1.5018 | $ 1.5000 | $ 1.5000

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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 + Details
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