Consolidated Statements of Stockholders' Equity - USD ($)
$ in Thousands
Total
Restricted stock units
Common Stock
Common Stock
Restricted stock units
Additional paid in capital
Additional paid in capital
Restricted stock units
Accumulated deficit
Accumulated other comprehensive income (loss)
Treasury Stock
Beginning Balance, Shares at May. 31, 2020     38,448,536,000            
Beginning Balance at May. 31, 2020 $ 454,872   $ 374   $ 561,871   $ (100,318) $ (1,341) $ (5,714)
Beginning Balance, Treasury Shares at May. 31, 2020                 (370,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                  
Net loss (4,268)           (4,268)    
Issuance/Cancellation of performance share units and restricted stock units, net, Shares       164,946,000          
Issuance/Cancellation of performance share units and restricted stock units   $ (143)       $ (143)      
Purchase of common stock under ESPP, Shares     79,596,000            
Purchases of common stock under ESPP 634   $ 1   633        
Stock-based compensation 1,864       1,864        
Other comprehensive income, net of tax 2,095             2,095  
Ending Balance, Shares at Aug. 31, 2020     38,693,078,000            
Ending Balance at Aug. 31, 2020 455,054   $ 375   564,225   (104,586) 754 $ (5,714)
Ending Balance, Treasury Shares at Aug. 31, 2020                 (370,000,000)
Beginning Balance, Shares at May. 31, 2020     38,448,536,000            
Beginning Balance at May. 31, 2020 454,872   $ 374   561,871   (100,318) (1,341) $ (5,714)
Beginning Balance, Treasury Shares at May. 31, 2020                 (370,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                  
Net loss (8,536)                
Ending Balance, Shares at Nov. 30, 2020     38,702,030,000            
Ending Balance at Nov. 30, 2020 454,343   $ 375   566,602   (108,854) 1,934 $ (5,714)
Ending Balance, Treasury Shares at Nov. 30, 2020                 (370,000,000)
Beginning Balance, Shares at Aug. 31, 2020     38,693,078,000            
Beginning Balance at Aug. 31, 2020 455,054   $ 375   564,225   (104,586) 754 $ (5,714)
Beginning Balance, Treasury Shares at Aug. 31, 2020                 (370,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                  
Net loss (4,268)           (4,268)    
Issuance/Cancellation of performance share units and restricted stock units, net, Shares       8,952,000          
Issuance/Cancellation of performance share units and restricted stock units   (10)       (10)      
Stock-based compensation 2,387       2,387        
Other comprehensive income, net of tax 1,180             1,180  
Ending Balance, Shares at Nov. 30, 2020     38,702,030,000            
Ending Balance at Nov. 30, 2020 454,343   $ 375   566,602   (108,854) 1,934 $ (5,714)
Ending Balance, Treasury Shares at Nov. 30, 2020                 (370,000,000)
Beginning Balance, Shares at May. 31, 2021     38,920,951,000            
Beginning Balance at May. 31, 2021 $ 439,457   $ 377   573,507   (131,866) 3,153 $ (5,714)
Beginning Balance, Treasury Shares at May. 31, 2021 (370,000)               (370,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                  
Net loss $ (6,972)           (6,972)    
Exercise of stock options, Shares     80,635,000            
Exercise of stock options 1,280   $ 1   1,279        
Issuance/Cancellation of performance share units and restricted stock units, net, Shares     59,371,000 279,495,000          
Issuance/Cancellation of performance share units and restricted stock units   (1,734)       (1,734)      
Purchase of common stock under ESPP, Shares     49,789,000            
Purchases of common stock under ESPP 900   $ 1   899        
Stock-based compensation 2,429       2,429        
Other comprehensive income, net of tax 590             590  
Ending Balance, Shares at Aug. 31, 2021     39,390,241,000            
Ending Balance at Aug. 31, 2021 435,950   $ 379   576,380   (138,838) 3,743 $ (5,714)
Ending Balance, Treasury Shares at Aug. 31, 2021                 (370,000,000)
Beginning Balance, Shares at May. 31, 2021     38,920,951,000            
Beginning Balance at May. 31, 2021 $ 439,457   $ 377   573,507   (131,866) 3,153 $ (5,714)
Beginning Balance, Treasury Shares at May. 31, 2021 (370,000)               (370,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                  
Net loss $ (15,323)                
Ending Balance, Shares at Nov. 30, 2021     39,455,193,000            
Ending Balance at Nov. 30, 2021 $ 432,368   $ 379   580,330   (147,189) 4,562 $ (5,714)
Ending Balance, Treasury Shares at Nov. 30, 2021 (370,000)               (370,000,000)
Beginning Balance, Shares at Aug. 31, 2021     39,390,241,000            
Beginning Balance at Aug. 31, 2021 $ 435,950   $ 379   576,380   (138,838) 3,743 $ (5,714)
Beginning Balance, Treasury Shares at Aug. 31, 2021                 (370,000,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                  
Net loss (8,351)                
Exercise of stock options, Shares     56,064,000            
Exercise of stock options 1,022       1,022        
Issuance/Cancellation of performance share units and restricted stock units, net, Shares       8,695,000          
Issuance/Cancellation of performance share units and restricted stock units   $ (83)       $ (83)      
Purchase of common stock under ESPP, Shares     193,000            
Purchases of common stock under ESPP 3       3        
Stock-based compensation 3,008       3,008        
Other comprehensive income, net of tax 819             819  
Ending Balance, Shares at Nov. 30, 2021     39,455,193,000            
Ending Balance at Nov. 30, 2021 $ 432,368   $ 379   $ 580,330   $ (147,189) $ 4,562 $ (5,714)
Ending Balance, Treasury Shares at Nov. 30, 2021 (370,000)               (370,000,000)