Note 4. Fair Value Measures (Tables)

3 Months Ended

Nov. 30, 2012

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Fair Value Measurements at Reporting Date Using
November 30, 2012	Level 1		Level 2		Level 3		Total
Assets
Corporate money market funds (1)	$	170,222	$	0	$	0	$	170,222
Certificates of deposit (2)		0		14,527		0		14,527
Total assets measured at fair value	$	170,222	$	14,527	$	0	$	184,749
Liabilities
Derivative instruments (3)	$	0	$	343	$	0	$	343
Total liabilities measured at fair value	$	0	$	343	$	0	$	343

	Fair Value Measurements at Reporting Date Using
August 31, 2012	Level 1		Level 2		Level 3		Total
Assets
Corporate money market funds (1)	$	160,169	$	0	$	0	$	160,169
Certificates of deposit (2)		0		13,919		0		13,919
Total assets measured at fair value	$	160,169	$	13,919	$	0	$	174,088
Liabilities
Derivative instruments (3)	$	0	$	2,374	$	0	$	2,374
Total liabilities measured at fair value	$	0	$	2,374	$	0	$	2,374

Carrying (Reported) Amount, Fair Value Disclosure [Member]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Fair Value Measurements at Reporting Date Using
November 30, 2012	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	170,222	$	0	$	0	$	170,222
Investments (short-term)		0		14,527		0		14,527
Total assets measured at fair value	$	170,222	$	14,527	$	0	$	184,749
Accounts payable and accrued liabilities (derivative liabilities)	$	0	$	343	$	0	$	343
Total liabilities measured at fair value	$	0	$	343	$	0	$	343

	Fair Value Measurements at Reporting Date Using
August 31, 2012	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	160,169	$	0	$	0	$	160,169
Investments (short-term)		0		13,919		0		13,919
Total assets measured at fair value	$	160,169	$	13,919	$	0	$	174,088
Accounts payable and accrued liabilities (derivative liabilities)	$	0	$	2,374	$	0	$	2,374
Total liabilities measured at fair value	$	0	$	2,374	$	0	$	2,374