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Subsequent Events - Additional Information (Detail) - $ / shares
Jun. 15, 2018
Mar. 26, 2018
Subsequent Event [Member]    
Subsequent Event [Line Items]    
Dividend payable date Aug. 03, 2018  
Dividend payable, date of record Jul. 06, 2018  
Common Stock [Member]    
Subsequent Event [Line Items]    
Dividend payable per share   $ 0.20
Common Stock [Member] | Subsequent Event [Member]    
Subsequent Event [Line Items]    
Dividend payable per share $ 0.225