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Subsequent Events - Monthly Distributions Declared by Company's Board of Directors (Detail) - Subsequent Event [Member] | Oct. 11, 2016 $ / shares
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Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | $ 0.2625
Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.4843749
Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.46875
Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.4374999
Common Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | $ 0.375
Installment 1 - FY2016 [Member] |
Dividends Payable [Line Items] |
Record Date | Oct. 21, 2016
Payment Date | Oct. 31, 2016
Installment 1 - FY2016 [Member] | Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Payment Date | Nov. 07, 2016
Distribution per Share (in dollars per share) | $ 0.0875
Installment 1 - FY2016 [Member] | Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.1614583
Installment 1 - FY2016 [Member] | Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.15625
Installment 1 - FY2016 [Member] | Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.1458333
Installment 1 - FY2016 [Member] | Common Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | $ 0.125
Installment 2 - FY2016 [Member] |
Dividends Payable [Line Items] |
Record Date | Nov. 17, 2016
Payment Date | Nov. 30, 2016
Installment 2 - FY2016 [Member] | Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Payment Date | Dec. 07, 2016
Distribution per Share (in dollars per share) | $ 0.0875
Installment 2 - FY2016 [Member] | Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.1614583
Installment 2 - FY2016 [Member] | Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.15625
Installment 2 - FY2016 [Member] | Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.1458333
Installment 2 - FY2016 [Member] | Common Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | $ 0.125
Installment 3 - FY2016 [Member] |
Dividends Payable [Line Items] |
Record Date | Dec. 20, 2016
Payment Date | Dec. 30, 2016
Installment 3 - FY2016 [Member] | Senior Common Stock [Member] |
Dividends Payable [Line Items] |
Payment Date | Jan. 09, 2017
Distribution per Share (in dollars per share) | $ 0.0875
Installment 3 - FY2016 [Member] | Series A Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.1614583
Installment 3 - FY2016 [Member] | Series B Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.15625
Installment 3 - FY2016 [Member] | Series D Preferred Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (in dollars per share) | 0.1458333
Installment 3 - FY2016 [Member] | Common Stock [Member] |
Dividends Payable [Line Items] |
Distribution per Share (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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