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Subsequent Events - Additional Information (Detail) - $ / shares
3 Months Ended
Apr. 12, 2018
Jan. 22, 2018
Mar. 31, 2018
Mar. 31, 2017
Subsequent Event [Line Items]        
Dividends per share declared on outstanding common stock   $ 0.14 $ 0.14 $ 0.14
Dividends payable date   Mar. 12, 2018    
Dividends payable, shareholders record date   Feb. 28, 2018    
Subsequent Event [Member]        
Subsequent Event [Line Items]        
Dividend declared date Apr. 12, 2018      
Dividends per share declared on outstanding common stock $ 0.14      
Dividends payable date May 04, 2018      
Dividends payable, shareholders record date Apr. 27, 2018