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Subsequent Events - Monthly Distributions Declared by Company's Board of Directors (Detail) - Subsequent Event [Member] | Jan. 12, 2017 $ / shares
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Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.4843749
Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | 0.46875
Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | 0.4375
Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | 0.2625
Common Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.375
Dividend Declared for Month of January [Member] |
Dividends Payable [Line Items] |
Record date | Jan. 20, 2017
Payment date | Jan. 31, 2017
Dividend Declared for Month of January [Member] | Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.1614583
Dividend Declared for Month of January [Member] | Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | 0.15625
Dividend Declared for Month of January [Member] | Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.1458333
Dividend Declared for Month of January [Member] | Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Payment date | Feb. 07, 2017
Month in which distribution is payable to holders of record | January
Distributions (in dollars per share) | $ 0.0875
Dividend Declared for Month of January [Member] | Common Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.125
Dividend Declared for Month of February [Member] |
Dividends Payable [Line Items] |
Record date | Feb. 16, 2017
Payment date | Feb. 28, 2017
Dividend Declared for Month of February [Member] | Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.1614583
Dividend Declared for Month of February [Member] | Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | 0.15625
Dividend Declared for Month of February [Member] | Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.1458333
Dividend Declared for Month of February [Member] | Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Payment date | Mar. 07, 2017
Month in which distribution is payable to holders of record | February
Distributions (in dollars per share) | $ 0.0875
Dividend Declared for Month of February [Member] | Common Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.125
Dividend Declared for Month of March [Member] |
Dividends Payable [Line Items] |
Record date | Mar. 22, 2017
Payment date | Mar. 31, 2017
Dividend Declared for Month of March [Member] | Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.1614583
Dividend Declared for Month of March [Member] | Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | 0.15625
Dividend Declared for Month of March [Member] | Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.1458333
Dividend Declared for Month of March [Member] | Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Payment date | Apr. 07, 2017
Month in which distribution is payable to holders of record | March
Distributions (in dollars per share) | $ 0.0875
Dividend Declared for Month of March [Member] | Common Stock [Member] |
Dividends Payable [Line Items] |
Distributions (in dollars per share) | $ 0.125

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- Definition Date the declared dividend will be paid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition The per share amount of a dividend declared, but not paid, as of the financial reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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