Note 6. Segment Information (Detail) - Results of Operations (USD $) In Thousands, unless otherwise specified	2 Months Ended	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2012		Aug. 31, 2011		Aug. 31, 2010
Revenues from clients		$ 805,793	[1]	$ 726,510	[1]	$ 641,059	[1]
Segment operating profit		272,990		238,335		221,634
Total assets	694,143	694,143		657,440		644,608
Depreciation and amortization		33,779		36,847		37,343
Stock-based compensation	500	21,982		25,773		14,065
Capital expenditures		22,520		29,343		20,768
United States [Member]
Revenues from clients		550,474	[1]	497,564	[1]	435,351	[1]
Segment operating profit		149,968		135,327		124,976
Total assets	377,320	377,320		353,205		401,684
Depreciation and amortization		25,061		27,463		28,866
Stock-based compensation		20,180		23,091		12,471
Capital expenditures		20,408		20,588		13,890
Europe [Member]
Revenues from clients		197,404		178,693		161,649
Segment operating profit		95,417		79,637		72,239
Total assets	266,967	266,967		274,139		216,171
Depreciation and amortization		4,922		6,092		6,466
Stock-based compensation		1,680		2,364		1,424
Capital expenditures		488		2,770		684
Asia Pacific [Member]
Revenues from clients		57,915	[1]	50,253	[1]	44,059	[1]
Segment operating profit		27,605		23,371		24,419
Total assets	49,856	49,856		30,096		26,753
Depreciation and amortization		3,796		3,292		2,011
Stock-based compensation		122		318		170
Capital expenditures		$ 1,624		$ 5,985		$ 6,194

[1] Revenues are attributed to countries based on the location of the client.