Note 3. Fair Value Measures (Detail) - Assets and Liabilities Measured at Fair Value (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012		Aug. 31, 2011
Assets at fair value	$ 174,088		$ 162,065
Liabilities at fair value	2,374	[1]
Accounts payable and accrued liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities at fair value	2,374
Accounts payable and accrued liabilities [Member]
Liabilities at fair value	2,374
Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Assets at fair value	160,169		161,168
Cash Equivalents [Member]
Assets at fair value	160,169		161,168
Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets at fair value	13,919
Investments [Member]
Assets at fair value	13,919
Prepaid Expenses and Other Current Assets [Member] | Fair Value, Inputs, Level 2 [Member]
Assets at fair value			897
Prepaid Expenses and Other Current Assets [Member]
Assets at fair value			897
Fair Value, Inputs, Level 1 [Member]
Assets at fair value	160,169		161,168
Liabilities at fair value		[1]
Fair Value, Inputs, Level 2 [Member]
Assets at fair value	13,919		897
Liabilities at fair value	2,374	[1]
Fair Value, Inputs, Level 3 [Member]
Liabilities at fair value		[1]

[1] The Company utilizes the income approach to measure fair value for its derivative instruments (foreign exchange forward contracts). The income approach uses pricing models that rely on market observable inputs such as spot, forward and interest rates, as well as credit default swap spreads and therefore are classified as Level 2.