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STOCK-BASED COMPENSATION - Summary of Restricted Stock Activity (Detail) - Restricted Stock - $ / shares
6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Shares    
Nonvested stock outstanding at beginning of period, shares 184,885 191,397
Granted, shares 222,390 86,984
Vested, shares (80,558) (72,393)
Nonvested stock outstanding at end of period, shares 326,717 205,988
Weighted-Average Grant Date Fair Value Per Share    
Nonvested stock outstanding at beginning of period, Weighted-Average Grant-Date Fair Value (in dollars per share) $ 54.63 $ 57.12
Granted, Weighted-Average Grant-Date Fair Value (in dollars per share) 32.87 52.21
Vested, Weighted-Average Grant-Date Fair Value (in dollars per share) 55.34 57.75
Nonvested stock outstanding at end of period, Weighted-Average Grant-Date Fair Value (in dollars per share) $ 39.64 $ 54.82
Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 1 year  
Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 5 years