XML 147 R58.htm IDEA: XBRL DOCUMENT v3.7.0.1
Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] - $ / shares
Jul. 24, 2017
Jul. 17, 2017
Jul. 11, 2017
Subsequent Event [Line Items]      
Dividend paid     $ 0.105
Dividend record date Sep. 15, 2017   Jun. 15, 2017
Preferred dividend paid   $ 0.50  
Dividend distributed $ 0.11    
Dividend payment date Oct. 11, 2017    
Preferred dividend distributed $ 0.50    
8% Series B Cumulative Redeemable Perpetual Preferred Stock [Member]      
Subsequent Event [Line Items]      
Dividend record date Sep. 29, 2017 Jun. 30, 2017  
Dividend payment date Oct. 16, 2017