Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation Expense (Details)

v3.8.0.1
Stock-Based Compensation Expense (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Mar. 31, 2016
Mar. 31, 2015
Jul. 28, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Benefit (loss) from excess tax deduction from option exercises $ 0 $ (448) $ 92    
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net (481) (1,069) 92    
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition 3,519 3,402 $ 3,749    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]          
Exercised (in shares)     (69,704)    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]          
Exercised, weighted average exercise price (in dollars per share)     $ 21.97    
Stock compensation expense $ 3,519 3,402 $ 3,749    
Total fair value of options issued   385      
Target number of shares (in shares) 15,438        
Restricted Stock and Stock Option Plan [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Maximum number of shares of the company's common stock that may be awarded         2,767,171
2011 Long-term Incentive Plan [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Maximum number of shares of the company's common stock that may be awarded         2,893,341
Stock Options [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Intrinsic value of stock options exercised $ 648 $ 627 $ 384    
Vesting period (in years) 5 years        
Annual vesting percentage 20.00%        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]          
Options outstanding, beginning of period (in shares) 411,939.000 433,726 465,042    
Exercised (in shares) (42,956) (47,484) (29,056)    
Forfeited (in shares) (1,412) (2,802) (2,260)    
Options outstanding, end of period (in shares) 367,571.000 411,939.000 433,726    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]          
Options outstanding, weighted average exercise price (in dollars per share) $ 9.12 $ 8.94 $ 8.07 $ 8.12  
Granted, weighted average exercise price (in dollars per share)   19.64      
Exercised, weighted average exercise price (in dollars per share) 7.00 6.77 8.25    
Forfeited, weighted average exercise price (in dollars per share) 19.83 $ 19.58 $ 17.10    
Granted (in shares)   28,499      
Closing price (in dollars per share) $ 22.41        
Total unrecognized expense related to non-vested stock option awards $ 117        
Stock based compensation, recognition period 1 year 9 months 4 days        
Stock Options [Member] | Maximum [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]          
Expiration term 10 years        
Common Stock [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]          
Total fair value of options issued $ 411        
Performance Shares [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]          
Forfeited (in shares) 0 0 (8,669,000)    
Vested shares 0 0 31,658,000    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]          
Total unrecognized expense related to non-vested stock option awards $ 1,231        
Stock based compensation, recognition period 2 years 2 months 19 days        
Total fair value of options issued $ 1,420 $ 881 $ 1,113    
Amortization Period For The Fair Value Share Based Compsensation Award (in years) 3 years        
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period 50,799        
Adjusted EBITDA Awards [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]          
Target number of shares (in shares) 58,246        
Common Stock [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]          
Exercised (in shares) (42,636) (43,121) (29,056)