Annual report pursuant to Section 13 and 15(d)

Organization and Summary of Significant Accounting Policies - Additional Information (Detail)

v2.4.0.6
Organization and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)
 12 Months Ended
Apr. 30, 2013
Segment
Country
Apr. 30, 2012
Apr. 30, 2011
Dec. 31, 2011
Dec. 31, 2010
Organization And Summary Of Significant Accounting Policies [Line Items]          
Number of offices 87        
Number of countries in which entity operates 37        
Number of business segments 3        
Investments in affiliated companies maximum 50.00%        
Dividends received from unconsolidated subsidiary $ 1,897,000 $ 1,669,000 $ 1,608,000    
Restricted cash 2,900,000 10,000,000      
Realized loss of other-than-temporary impairment 0 0 0    
Reduction in the estimated fair value of contingent consideration relating to prior acquisition   (2,196,000) (4,919,000)    
Impairment of goodwill 0 0      
Intangible assets estimated useful lives 11 years        
Trademark written-off     880,000    
Performance related bonus expenses 114,100,000 116,800,000 128,300,000    
(Decrease) increase in performance related bonus expenses (200,000) (1,200,000) (2,000,000)    
Performance related bonus after reduction in the previous year estimate 113,900,000 115,600,000 126,300,000    
Deferred bonuses paid       5,400,000 10,200,000
Foreign currency losses, after tax basis 500,000 1,600,000      
Foreign currency gains, after tax basis     100,000    
Csv Of Coli Contracts
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Gross CSV 159,200,000 151,100,000      
Outstanding policy loans 73,300,000 73,300,000      
Receivable on insolvency of insurance companies $ 40,500,000 $ 35,400,000      
Executive Capital Accumulation Plan
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Deferred compensation arrangement vesting terms The Company amortizes these contributions on a straight-line basis as they vest, generally over a four year period.        
Minimum
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Intangible assets estimated useful lives 2 years        
Maximum
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Intangible assets estimated useful lives 24 years        
Software and Software Development Costs | Minimum
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Property and equipment, estimated useful life, maximum 3 years        
Software and Software Development Costs | Maximum
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Property and equipment, estimated useful life, maximum 7 years        
Other Capitalized Property Plant and Equipment | Minimum
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Property and equipment, estimated useful life, maximum 3 years        
Other Capitalized Property Plant and Equipment | Maximum
          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Property and equipment, estimated useful life, maximum 10 years