Note 17. Commitments and Contingencies (Detail) (USD $)	12 Months Ended
	Aug. 31, 2012 sqft	Aug. 31, 2011	Aug. 31, 2010
Increase in Leased Office Space (in Square feet)	807,000
Operating Leases, Future Minimum Payments Due	$ 141,171,000
Operating Leases, Future Minimum Payments Due, Next Twelve Months	100,000
Operating Leases Percentage Of Increase In Lease Area	11.00%
Operating Leases, Rent Expense	34,600,000	32,800,000	30,600,000
Line of Credit Facility, Amount Outstanding	4,300,000
Long-term Purchase Commitment, Amount	52,200,000	47,800,000
Line of Credit Facility, Maximum Borrowing Capacity	12,500,000
Line of Credit Facility, Commitment Fee Percentage	0.125%
Norwalk, Connecticut [Member]
Area of Real Estate Property (in Square feet)	193,000
Increase in Leased Office Space (in Square feet)	23,800
Operating Leases, Future Minimum Payments Due	3,800,000
Non Cancelable Lease Term Period	8 years
New York, New York [Member]
Area of Real Estate Property (in Square feet)	17,600
Operating Leases, Future Minimum Payments Due	3,100,000
Non Cancelable Lease Term Period	3 years 6 months
Hong Kong [Member]
Area of Real Estate Property (in Square feet)	3,000
Operating Leases, Future Minimum Payments Due	5,400,000
Non Cancelable Lease Term Period	6 years
Manila [Member]
Area of Real Estate Property (in Square feet)	22,900
Operating Leases, Future Minimum Payments Due	2,100,000
Non Cancelable Lease Term Period	5 years
Dubai, United Arab Emirates [Member]
Increase in Leased Office Space (in Square feet)	1,600
Operating Leases, Future Minimum Payments Due	800,000
Non Cancelable Lease Term Period	3 years
StreetAccount [Member]
Increase in Leased Office Space (in Square feet)	9,500
Operating Leases, Future Minimum Payments Due	$ 500,000
East Grinstead [Member]
Non Cancelable Lease Term Period	7 months
Reduction In Leased Office Space (in Square feet)	3,853