Basis Of Presentation And Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	May 31, 2021	May 31, 2020	May 31, 2021	May 31, 2020	Aug. 31, 2020
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Realized foreign currency transactions	$ 0	$ 0	$ 0	$ 0
Unrealized foreign currency transactions			529,000	$ (30,000)
Carrying value of senior notes	116,498,000		116,498,000		$ 113,098,000
Assets	427,887,000		427,887,000		362,637,000
Liabilities	225,255,000		225,255,000		202,324,000
Foreign Currency Forward Contracts [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Foreign currency forward contracts outstanding	15,800,000		$ 15,800,000
Foreign currency forward contracts, Maturity date			Jun. 29, 2021
Unrealized foreign currency transactions			$ 0		$ 0
Level 2 [Member] | Recurring [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Assets	0		0
Liabilities	0		0
Level 2 [Member] | Nonrecurring [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Assets	0		0
Liabilities	0		0
Senior Notes [Member] | Level 2 [Member]
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]
Fair value of senior notes	66,400,000		66,400,000
Carrying value of senior notes	$ 69,200,000		$ 69,200,000