XML 57 R41.htm IDEA: XBRL DOCUMENT v2.4.0.8
Debt - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Jul. 31, 2014
Apr. 30, 2014
Feb. 21, 2014
Nov. 04, 2008
Jul. 31, 2014
Unused lines of Credit
Apr. 30, 2014
Unused lines of Credit
Jul. 31, 2014
Revolving Credit Facility
Amendment Five
Jul. 31, 2014
Combined Letter Of Credit And Credit Card Services Sub facility
Jul. 31, 2014
Line of Credit
Jul. 31, 2014
Line of Credit
Daily adjusting LIBOR rate
Jul. 31, 2014
Line of Credit
Amendment Agreement
Debt Instrument [Line Items]                      
Revolving line of credit with a borrowing capacity             $ 30.0 $ 2.7      
Line of credit facility current borrowing capacity percentage             100.00%        
Loan and security agreement, issue date                 Jul. 18, 2007   Jun. 30, 2013
Loan and security agreement, expiration date                 Jan. 31, 2015    
Interest above daily adjusting LIBOR rate                   2.50%  
Letter of credit drawn 1.6 1.6   0.5              
Revolving line of credit drawn     27.0                
Unused revolving line of credit         $ 1.4 $ 1.4