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STOCK COMPENSATION PLAN - Additional Information (Details) - USD ($)
1 Months Ended 9 Months Ended 12 Months Ended
Apr. 17, 2017
Apr. 15, 2017
Jul. 31, 2014
Sep. 30, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Apr. 15, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Shares reserved for issuance (in shares)         6,565,000      
Shares remaining available for grants (in shares)         3,400,000      
Term of plan     7 years          
Share based payment award options vesting period range start         1 year      
Share based payment award options vesting period range end         4 years      
Options exercisable (in shares)         0 0 0  
Closing price (usd per share)         $ 26.00     $ 36.97
Shares withheld for withholding taxes (in shares)         89,620 92,092 82,740  
Segment reconciling items                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Compensation expense       $ 6,400,000 $ 6,800,000 $ 6,400,000 $ 5,100,000  
Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Share based payment award period range start         2 years      
Share based payment award period range end         5 years      
Restricted stock granted (in shares)         853,111 125,540 220,635  
Fair value of restricted stock and restricted stock units vested         $ 7,000,000 $ 6,500,000    
Deferred stock-based compensation related to restricted stock awards         19,400,000      
Weighted average remaining contractual terms           3 years 3 months    
Chief Executive Officer [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Vesting period   5 years            
Shares withheld for withholding taxes (in shares)   30,197            
Chief Executive Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Restricted stock granted (in shares)   270,489            
Common stock equivalent value to shares granted   $ 10,000,000            
Chief Financial Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Common stock equivalent value to shares granted         $ 5,000,000      
Chief Operating Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Restricted stock granted (in shares) 192,307              
First Anniversary [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Vesting period         2 years 3 years 4 years  
First Anniversary [Member] | Chief Executive Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage   20.00%            
First Anniversary [Member] | Chief Operating Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage 20.00%              
Second Anniversary [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Vesting period         5 years 4 years 5 years  
Second Anniversary [Member] | Chief Executive Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage   20.00%            
Second Anniversary [Member] | Chief Operating Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage 20.00%              
Third Anniversary [Member] | Chief Executive Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage   20.00%            
Third Anniversary [Member] | Chief Operating Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage 20.00%              
Fourth Anniversary [Member] | Chief Executive Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage   20.00%            
Fourth Anniversary [Member] | Chief Operating Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage 20.00%              
Fifth Anniversary [Member] | Chief Executive Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage   20.00%            
Fifth Anniversary [Member] | Chief Operating Officer [Member] | Restricted Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award vesting percentage 20.00%              
Class A Common Stock                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Award requisite service period         7 years