Fair Value Measures (Assets And Liabilities Measured At Fair Value Reported In Statements Of Financial Condition) (Details) (USD $) In Thousands	Aug. 31, 2011	Aug. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	$ 161,168	$ 172,218
Other current assets (derivative assets)	897	879
Total assets measured at fair value	162,065	173,097
Derivative liabilities	0	1,220
Total liabilities measured at fair value	0	1,220
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	161,168	172,218
Other current assets (derivative assets)	0	0
Total assets measured at fair value	161,168	172,218
Derivative liabilities	0	0
Total liabilities measured at fair value	0	0
Level 1 [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	161,168	172,218
Level 1 [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets (derivative assets)		0
Level 1 [Member] | Accounts Payable And Accrued Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Level 1 [Member] | Deferred Rent And Other Non-Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	0	0
Other current assets (derivative assets)	897	879
Total assets measured at fair value	897	879
Derivative liabilities	0	1,220
Total liabilities measured at fair value	0	1,220
Level 2 [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	0	0
Level 2 [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets (derivative assets)	897	879
Level 2 [Member] | Accounts Payable And Accrued Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	1,027
Level 2 [Member] | Deferred Rent And Other Non-Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	193
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	0	0
Other current assets (derivative assets)	0	0
Total assets measured at fair value	0	0
Derivative liabilities	0	0
Total liabilities measured at fair value	0	0
Level 3 [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	0	0
Level 3 [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets (derivative assets)		0
Level 3 [Member] | Accounts Payable And Accrued Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Level 3 [Member] | Deferred Rent And Other Non-Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate money market funds	161,168	172,218
Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets (derivative assets)	897	879
Accounts Payable And Accrued Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	1,027
Deferred Rent And Other Non-Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	$ 0	$ 193