XML 18 R50.htm IDEA: XBRL DOCUMENT v2.4.0.8
Acquisitions - Additional Information (Detail) (USD $)
 3 Months Ended 9 Months Ended
Jan. 31, 2014
Jan. 31, 2014
Business Acquisition [Line Items]    
Acquisition of a business, contingent consideration   $ 15,000,000
PDI Ninth House
    
Business Acquisition [Line Items]    
Business acquisition, adjustments to the preliminary purchase price allocation, increase in net assets acquired 100,000  
Business acquisition, adjustments to the preliminary purchase price allocation, increase in the purchase price   200,000
Business acquisition, adjustments to the preliminary purchase price allocation, increase (decrease) in Goodwill (100,000) 200,000
Acquisition of a business, contingent consideration   $ 15,000,000