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Equity and Mezzanine Equity - Summary of Changes in Stockholders' Equity (Detail) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Ordinary Income | Common Stock and Non-controlling OP Units |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, dividend rate (as percent) | 37.28754% | 44.46159% | 24.46913%
Ordinary Income | Senior Common Stock |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, dividend rate (as percent) | 100.00% | 100.00% | 100.00%
Ordinary Income | Series A Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 100.00% | 100.00%
Ordinary Income | Series B Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 100.00% | 100.00%
Ordinary Income | Series D Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 100.00% | 100.00% | 100.00%
Ordinary Income | Series E Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 100.00% | 100.00% | 0.00%
Ordinary Income | Series F Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 100.00% | 0.00% | 0.00%
Return of Capital | Common Stock and Non-controlling OP Units |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, dividend rate (as percent) | 62.71246% | 55.53841% | 75.53087%
Return of Capital | Senior Common Stock |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Return of Capital | Series A Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Return of Capital | Series B Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Return of Capital | Series D Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Return of Capital | Series E Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Return of Capital | Series F Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Long-Term Capital Gains | Common Stock and Non-controlling OP Units |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Long-Term Capital Gains | Senior Common Stock |  |  |
Dividends Payable [Line Items] |  |  |
Common stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Long-Term Capital Gains | Series A Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Long-Term Capital Gains | Series B Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Long-Term Capital Gains | Series D Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Long-Term Capital Gains | Series E Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%
Long-Term Capital Gains | Series F Preferred Stock |  |  |
Dividends Payable [Line Items] |  |  |
Preferred stock, dividend rate (as percent) | 0.00% | 0.00% | 0.00%

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