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Equity and Mezzanine Equity - Dividends Paid (Detail) - $ / shares | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 2018
Senior Common Stock |  |
Dividends Payable [Line Items] |  |
Common Stock, dividends paid per share | $ 0.2625 | $ 0.2625
Series A Preferred Stock |  |
Dividends Payable [Line Items] |  |
Preferred Stock, dividends paid per share | 0.4843749 | 0.4843749
Series B Preferred Stock |  |
Dividends Payable [Line Items] |  |
Preferred Stock, dividends paid per share | 0.46875 | 0.46875
Series D Preferred Stock |  |
Dividends Payable [Line Items] |  |
Preferred Stock, dividends paid per share | 0.4374999 | 0.4374999
Common Stock |  |
Dividends Payable [Line Items] |  |
Common Stock, dividends paid per share | $ 0.375 | $ 0.375

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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=27012166&loc=d3e187085-122770 + Details
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- Definition Aggregate dividends paid during the period for each share of preferred stock outstanding. + References No definition available. + Details
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