Quarterly report pursuant to Section 13 or 15(d)

Subsequent Events - Monthly Distributions Declared by Company's Board of Directors (Detail)

v3.5.0.2
Subsequent Events - Monthly Distributions Declared by Company's Board of Directors (Detail) - $ / shares
shares in Thousands
Jul. 12, 2016
Feb. 29, 2012
Dividends Payable [Line Items]    
Preferred shares at a redemption price (in dollars per share)   $ 25.00
Subsequent Event [Member]    
Dividends Payable [Line Items]    
Preferred stock to be redeemed (in shares) 540  
Preferred shares at a redemption price (in dollars per share) $ 25.00  
Subsequent Event [Member] | Senior Common Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.002625  
Subsequent Event [Member] | Series A Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.004843749  
Subsequent Event [Member] | Series B Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.0046875  
Subsequent Event [Member] | Series C Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001484375  
Subsequent Event [Member] | Series D Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.004374999  
Subsequent Event [Member] | Common Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) $ 0.00375  
Subsequent Event [Member] | Installment 1 - FY2016 [Member]    
Dividends Payable [Line Items]    
Record Date Jul. 22, 2016  
Payment Date Aug. 02, 2016  
Subsequent Event [Member] | Installment 1 - FY2016 [Member] | Senior Common Stock [Member]    
Dividends Payable [Line Items]    
Payment Date Aug. 05, 2016  
Distribution per Share (in dollars per share) $ 0.000875  
Subsequent Event [Member] | Installment 1 - FY2016 [Member] | Series A Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001614583  
Subsequent Event [Member] | Installment 1 - FY2016 [Member] | Series B Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.0015625  
Subsequent Event [Member] | Installment 1 - FY2016 [Member] | Series C Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001484375  
Subsequent Event [Member] | Installment 1 - FY2016 [Member] | Series D Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001458333  
Subsequent Event [Member] | Installment 1 - FY2016 [Member] | Common Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) $ 0.00125  
Subsequent Event [Member] | Installment 2 - FY2016 [Member]    
Dividends Payable [Line Items]    
Record Date Aug. 22, 2016  
Payment Date Aug. 31, 2016  
Subsequent Event [Member] | Installment 2 - FY2016 [Member] | Senior Common Stock [Member]    
Dividends Payable [Line Items]    
Payment Date Sep. 08, 2016  
Distribution per Share (in dollars per share) $ 0.000875  
Subsequent Event [Member] | Installment 2 - FY2016 [Member] | Series A Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001614583  
Subsequent Event [Member] | Installment 2 - FY2016 [Member] | Series B Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.0015625  
Subsequent Event [Member] | Installment 2 - FY2016 [Member] | Series C Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0  
Subsequent Event [Member] | Installment 2 - FY2016 [Member] | Series D Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001458333  
Subsequent Event [Member] | Installment 2 - FY2016 [Member] | Common Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) $ 0.00125  
Subsequent Event [Member] | Installment 3 - FY2016 [Member]    
Dividends Payable [Line Items]    
Record Date Sep. 21, 2016  
Payment Date Sep. 30, 2016  
Subsequent Event [Member] | Installment 3 - FY2016 [Member] | Senior Common Stock [Member]    
Dividends Payable [Line Items]    
Payment Date Oct. 07, 2016  
Distribution per Share (in dollars per share) $ 0.000875  
Subsequent Event [Member] | Installment 3 - FY2016 [Member] | Series A Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001614583  
Subsequent Event [Member] | Installment 3 - FY2016 [Member] | Series B Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.0015625  
Subsequent Event [Member] | Installment 3 - FY2016 [Member] | Series C Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0  
Subsequent Event [Member] | Installment 3 - FY2016 [Member] | Series D Preferred Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) 0.001458333  
Subsequent Event [Member] | Installment 3 - FY2016 [Member] | Common Stock [Member]    
Dividends Payable [Line Items]    
Distribution per Share (in dollars per share) $ 0.00125