Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Summary of Changes in Stockholders' Equity (Detail)

v3.3.1.900
Stockholders' Equity - Summary of Changes in Stockholders' Equity (Detail)
 1 Months Ended 12 Months Ended
Feb. 29, 2012
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Series C Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock 7.125%      
Ordinary Income [Member] | Common Stock [Member]        
Dividends Payable [Line Items]        
Common stock   18.80114% 0.00% 18.32962%
Ordinary Income [Member] | Senior Common Stock [Member]        
Dividends Payable [Line Items]        
Common stock   91.71368% 0.00% 100.00%
Ordinary Income [Member] | Series A Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   91.71368% 24.10732% 100.00%
Ordinary Income [Member] | Series B Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   91.71368% 24.10732% 100.00%
Ordinary Income [Member] | Series C Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   91.71368% 24.10732% 100.00%
Return of Capital [Member] | Common Stock [Member]        
Dividends Payable [Line Items]        
Common stock   79.50018% 100.00% 81.67038%
Return of Capital [Member] | Senior Common Stock [Member]        
Dividends Payable [Line Items]        
Common stock   0.00% 100.00% 0.00%
Return of Capital [Member] | Series A Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   0.00% 75.89268% 0.00%
Return of Capital [Member] | Series B Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   0.00% 75.89268% 0.00%
Return of Capital [Member] | Series C Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   0.00% 75.89268% 0.00%
Long Term Capital Gains [Member] | Common Stock [Member]        
Dividends Payable [Line Items]        
Common stock   1.69868% 0.00% 0.00%
Long Term Capital Gains [Member] | Senior Common Stock [Member]        
Dividends Payable [Line Items]        
Common stock   8.28632% 0.00% 0.00%
Long Term Capital Gains [Member] | Series A Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   8.28632% 0.00% 0.00%
Long Term Capital Gains [Member] | Series B Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   8.28632% 0.00% 0.00%
Long Term Capital Gains [Member] | Series C Preferred Stock [Member]        
Dividends Payable [Line Items]        
Preferred stock   8.28632% 0.00% 0.00%