Fair Value Measurements (Schedule of Financial Assets and Liabilities Measured at Fair Value) (Details) - USD ($) $ in Thousands	Feb. 28, 2019	Aug. 31, 2018	Feb. 28, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 102,778	$ 160,787	$ 102,211
Derivative assets	426	898	19
Derivative liabilities	(22)	(12)	(1,010)
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	102,778	160,787	102,211
Derivative assets	0	0	0
Derivative liabilities	0	0	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0	0
Derivative assets	426	898	19
Derivative liabilities	(22)	(12)	(1,010)
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0	0
Derivative assets	0	0	0
Derivative liabilities	$ 0	$ 0	$ 0