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Share-Based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 10, 2017
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Recognized share-based compensation awards   $ 700,000 $ 600,000 $ 700,000 $ 1,100,000
Number of stock option granted   128,000 0 128,000 100,000
Weighted-average fair value of stock options granted       $ 2.68 $ 2.07
Expected Volatility Rate       39.00% 39.00%
Expected Term Period       6 years 3 months 18 days 6 years 6 months
Risk-Free Interest Rate       2.10% 2.10%
Expected dividend rate       3.30% 3.60%
Number of options exercised       282,000 51,000
Cash received from employees and directors stock option exercised       $ 1,100,000 $ 300,000
Intrinsic value of option exercised       $ 1,800,000 $ 100,000
Restricted Stock Units [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of stock awards granted   351,000 90,000 405,000 100,000
Weighted-average fair value of restricted stock unit granted       $ 9.87 $ 7.77
Performance Units [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common stock price threshold consecutive trading days       30 days  
Period to earn units based on stock price during thirty consecutive trading days       2 years  
Share-based payment award vesting period       3 years  
Maximum shares of common stock participant could receive per performance       77,778  
Performance Units [Member] | Chief Executive Officer [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of stock awards granted 700,000        
Value of stock awards granted $ 175,000