Fair Value Measurements (Schedule of Financial Assets and Liabilities Measured at Fair Value) (Details) - USD ($) $ in Thousands	Feb. 29, 2020	Aug. 31, 2019	Feb. 28, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 101,272	$ 127,204	$ 102,778
Marketable securities:
Marketable securities	18,700
Derivative assets	247	1,112	426
Derivative liabilities			(22)
Corporate Bonds [Member]
Marketable securities:
Marketable securities	14,555
U.S. Treasury Securities [Member]
Marketable securities:
Marketable securities	4,185
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	101,272	127,204	102,778
Marketable securities:
Derivative assets	0	0	0
Derivative liabilities			0
Level 1 [Member] | Corporate Bonds [Member]
Marketable securities:
Marketable securities	0
Level 1 [Member] | U.S. Treasury Securities [Member]
Marketable securities:
Marketable securities	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0	0
Marketable securities:
Derivative assets	247	1,112	426
Derivative liabilities			(22)
Level 2 [Member] | Corporate Bonds [Member]
Marketable securities:
Marketable securities	14,555
Level 2 [Member] | U.S. Treasury Securities [Member]
Marketable securities:
Marketable securities	4,185
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0	0
Marketable securities:
Derivative assets	0	$ 0	0
Derivative liabilities			$ 0
Level 3 [Member] | Corporate Bonds [Member]
Marketable securities:
Marketable securities	0
Level 3 [Member] | U.S. Treasury Securities [Member]
Marketable securities:
Marketable securities	$ 0