Basis Of Presentation (Schedule Of Cumulative After-Tax Effects On Balance Sheet) (Details) - USD ($) $ in Thousands	Nov. 30, 2018	Sep. 01, 2018	Aug. 31, 2018
Assets:
Deferred income tax assets	$ 4,877		$ 3,222
Liabilities and Shareholders' Equity:
Deferred revenue	46,221		51,888
Other liabilities	7,747		5,501
Retained earnings	59,069		63,569
Accounting Standards Update 2014-09 [Member]
Assets:
Other current assets		$ 11,002	10,893
Deferred income tax assets	4,877	4,227	3,222
Liabilities and Shareholders' Equity:
Deferred revenue	46,221	53,896	51,888
Other liabilities	7,747	7,750	5,501
Retained earnings	$ 59,069	60,426	$ 63,569
ASC 606 Adjustments [Member] | Accounting Standards Update 2014-09 [Member]
Assets:
Other current assets		109
Deferred income tax assets		1,005
Liabilities and Shareholders' Equity:
Deferred revenue		2,008
Other liabilities		2,249
Retained earnings		$ (3,143)