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STOCK-BASED COMPENSATION (Details) - USD ($)
3 Months Ended 9 Months Ended 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Mar. 31, 2017
Mar. 31, 2016
Mar. 31, 2014
Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Document Fiscal Year Focus     2018          
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 338,489 746,274 392,609 734,155        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate 0.00% 0.00% 0.00% 0.00%        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate 53.02% 48.83% 52.97% 48.90%        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate 1.97% 1.19% 1.97% 1.90%        
Stock Option Plans [Abstract]                
Number of shares available for grant (in shares) 1,280,821   1,280,821          
Weighted-average fair value at the grant date $ 39.63 $ 22.25 $ 39.33 $ 22.24        
Options Activity [Roll Forward]                
Exercised (in shares)     (155,710)   (33,702)      
Restricted Stock [Abstract]                
Grant date fair value (in dollars per share)         $ 51.15 $ 28.11    
Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]                
Grant date fair value (in dollars per share)         $ 51.15 $ 28.11    
Compensation related to stock option and restricted stock plans     $ 3,447,832 $ 3,905,977        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term 5 years 5 years 5 years 5 years 3 days        
Group B Performance Award [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Stock Issued During Period, Shares, Share-based Compensation, Gross             56,660 443,700
Stock Options Plans [Member]                
Stock Option Plans [Abstract]                
Shares of authorized common stock reserved for issuance (in shares) 4,950,000   4,950,000          
Options Activity [Roll Forward]                
Options outstanding, beginning of year (in shares)     860,741          
Granted (in shares)     57,320          
Exercised (in shares)     (155,710)          
Forfeited (in shares)     (15,459)          
Expired (in shares)     (14,144)          
Options outstanding, end of period (in shares) 732,748   732,748   860,741      
Options exercisable, end of period (in shares) 527,249   527,249          
Weighted Average Exercise Price [Roll Forward]                
Options outstanding, beginning of year (in dollars per share)     $ 67.28          
Granted (in dollars per share)     83.02          
Exercised (in dollars per share)     56.11          
Forfeited (in dollars per share)     63.14          
Expired (in dollars per share)     80.87          
Options outstanding, end of period (in dollars per share) $ 70.71   70.71   $ 67.28      
Options exercisable, end of period (in dollars per share) $ 71.47   $ 71.47          
Stock Option Activity Additional Disclosures [Abstract]                
Weighted-average remaining contractual term, Options outstanding, end of period     6 years 26 days          
Weighted-average remaining contractual terms, Options exercisable, end of period     5 years 3 months 26 days          
Aggregate intrinsic value, Options outstanding, end of period $ 8,815,506   $ 8,815,506          
Aggregate intrinsic value, Options exercisable, end of period 5,959,813   5,959,813          
Intrinsic value of options exercised 1,334,062 $ 500,137 4,010,659 $ 612,530        
Compensation Cost Not yet Recognized [Abstract]                
Total unrecognized stock-based compensation expense related to non-vested stock options 3,100,000   $ 3,100,000          
Weighted average period for recognition     2 years 4 months 2 days          
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Weighted average period for recognition     2 years 4 months 2 days          
Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]                
Compensation related to stock option and restricted stock plans 712,286 2,149,340 $ 1,834,513 3,131,760        
Group A Performance Award [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Stock Issued During Period, Shares, Share-based Compensation, Gross             8,590 70,800
Restricted Stock [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Stock Issued During Period, Shares, Share-based Compensation, Gross         74,490 69,950    
Restricted Stock [Abstract]                
Grant date fair value (in dollars per share)     $ 0.00          
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options $ 1,300,000   $ 1,300,000          
Summary of the status and changes in restricted stock [Roll Forward]                
Outstanding at Beginning of Year (in shares)     111,361          
Awards granted (in shares)     0          
Vested during the period, net of cancellations (in shares)     (42,880)          
Stock Issued During Period, Shares, Restricted Stock Award, Forfeited     0          
Outstanding at End of Period (in shares) 68,481   68,481   111,361      
Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]                
Outstanding at March 31, 2012 (in dollars per share)     $ 43.11          
Grant date fair value (in dollars per share)     0.00          
Vested during the period, net of cancellations (in dollars per share)     40.99          
Cancelled during the period (in dollars per share)     0.00          
Outstanding at June 30, 2012 (in dollars per share) $ 44.44   $ 44.44   $ 43.11      
Compensation related to stock option and restricted stock plans $ 323,201 618,023 $ 1,613,319 1,041,891        
Restricted Stock [Member] | EPS Target [Member] | $10.29 EPS [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     100.00%          
EPS Target     $ 10.29          
Restricted Stock [Member] | EPS Target [Member] | $9.76 EPS [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     67.00%          
EPS Target     $ 9.76          
Restricted Stock [Member] | EPS Target [Member] | $9.26 EPS [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     33.00%          
EPS Target     $ 9.26          
Restricted Stock [Member] | EPS Target [Member] | Below $9.26 EPS [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     0.00%          
EPS Target     $ 9.26          
Restricted Stock [Member] | Trailing Four Quarter EPS Target [Member] | $13.00 [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     25.00%          
EPS Target     $ 13.00          
Restricted Stock [Member] | Trailing Four Quarter EPS Target [Member] | $14.50 [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     25.00%          
EPS Target     $ 14.50          
Restricted Stock [Member] | Trailing Four Quarter EPS Target [Member] | $16.00 [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     25.00%          
EPS Target     $ 16.00          
Restricted Stock [Member] | Trailing Four Quarter EPS Target [Member] | $18.00 [Member]                
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Vesting Percentage (in hundredths)     25.00%          
EPS Target     $ 18.00          
Equity Securities [Member]                
Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]                
Compensation related to stock option and restricted stock plans $ 1,035,487 $ 2,767,363 $ 3,447,832 $ 4,173,651        
Performance Shares [Member]                
Compensation Cost Not yet Recognized [Abstract]                
Weighted average period for recognition     1 year 7 months 21 days          
Schedule of vesting of restricted shares on basis of compounded annual EPS growth [Abstract]                
Weighted average period for recognition     1 year 7 months 21 days          
Maximum [Member] | Stock Options Plans [Member]                
Stock Option Plans [Abstract]                
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period     10 years          
Vesting period     5 years          
Minimum [Member] | Stock Options Plans [Member]                
Stock Option Plans [Abstract]                
Vesting period     3 years