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Subsequent Event - Additional Information (Detail) - Subsequent Event [Member] - USD ($)
Mar. 02, 2018
Feb. 20, 2018
Subsequent Event [Line Items]    
Dividend declared $ 0.20  
Dividend payable date Apr. 16, 2018  
Dividend record date Mar. 26, 2018  
Related Party [Member]    
Subsequent Event [Line Items]    
Repurchased shares of common stock   100,000
Purchase price of common stock   $ 20.22