Condensed Consolidated Statement of Stockholders' Equity (USD $)
In Thousands, except Share data, unless otherwise specified
Total
Series C Preferred Stock [Member]
Series D Preferred Stock [Member]
Preferred Stock [Member]
Series D Preferred Stock [Member]
Common Stock [Member]
Additional Paid-in Capital [Member]
Retained Earnings (Deficit) [Member]
Retained Earnings (Deficit) [Member]
Series C Preferred Stock [Member]
Retained Earnings (Deficit) [Member]
Series D Preferred Stock [Member]
Balance at Apr. 30, 2014 $ 282,759     $ 25,041 $ 4 $ 98,788 $ 158,926    
Balance (in shares) at Apr. 30, 2014       1,070,448 45,756,697        
Increase (Decrease) in Stockholders' Equity [Roll Forward]                  
Net loss (11,854)           (11,854)    
Series C preferred stock dividends   (2,062)           (2,062)  
Accretion of Series C preferred stock   (694)           (694)  
Issuance of Series D preferred stock     1,542 1,542          
Issuance of Series D preferred stock (in shares)     62,304 62,304          
Series D preferred stock dividends     (884)           (884)
Accretion of Series D preferred stock     0 (128)         (128)
Issuance of equity for services 416         416      
Issuance of equity for compensation 1,645         1,645      
Issuance of equity for compensation (in shares)         40,010        
Exercise of equity rights 1,399       1 1,398      
Exercise of equity rights (in shares) 311,354       311,354        
Balance at Jul. 31, 2014 $ 272,267     $ 26,711 $ 5 $ 102,247 $ 143,304    
Balance (in shares) at Jul. 31, 2014       1,132,752 46,108,061