Basis Of Presentation (Balance Sheet Impacted By Adoption Of New Accounting Standard) (Details) - USD ($) $ in Thousands	Feb. 28, 2019	Sep. 01, 2018	Aug. 31, 2018
Assets:
Prepaid expenses and other current assets	$ 12,879		$ 14,757
Deferred income tax assets	5,652		3,222
Total assets	190,176		213,875
Liabilities and Shareholders' Equity:
Deferred revenue	45,209		51,888
Other liabilities	7,490		5,501
Retained earnings	55,552		63,569
Total liabilities and shareholders' equity	190,176		213,875
Accounting Standards Update 2014-09 [Member]
Assets:
Prepaid expenses and other current assets	12,879
Deferred income tax assets	5,652	$ 4,227	3,222
Total assets	190,176
Liabilities and Shareholders' Equity:
Deferred revenue	45,209	53,896	51,888
Other liabilities	7,490	7,750	5,501
Retained earnings	55,552	$ 60,426	$ 63,569
Total liabilities and shareholders' equity	190,176
Without ASC 606 [Member] | Accounting Standards Update 2014-09 [Member]
Assets:
Prepaid expenses and other current assets	12,853
Deferred income tax assets	4,989
Total assets	189,487
Liabilities and Shareholders' Equity:
Deferred revenue	44,262
Other liabilities	5,712
Retained earnings	57,588
Total liabilities and shareholders' equity	189,487
Impact Of ASC 606 [Member] | Accounting Standards Update 2014-09 [Member]
Assets:
Prepaid expenses and other current assets	26
Deferred income tax assets	663
Total assets	689
Liabilities and Shareholders' Equity:
Deferred revenue	947
Other liabilities	1,778
Retained earnings	(2,036)
Total liabilities and shareholders' equity	$ 689