Consolidated Statements Of Shareholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Treasury Stock [Member]	Total
Beginning balance, shares at Aug. 31, 2017	27,056,000				13,414,000
Beginning balance at Aug. 31, 2017	$ 1,353	$ 212,484	$ 69,456	$ 667	$ (198,895)
Issuance of common stock from treasury, shares					337,000
Issuance of common stock from treasury		(3,702)			$ 4,510
Purchase of treasury shares, shares					(105,000)
Purchase of treasury shares					$ (2,006)
Restricted share award, shares					23,000
Restricted share award		(348)			$ 348
Stock-based compensation		2,846
Cumulative translation adjustments				(326)		$ (326)
Net loss			(5,887)			(5,887)
Ending balance, shares at Aug. 31, 2018	27,056,000				13,159,000
Ending balance at Aug. 31, 2018	$ 1,353	211,280	63,569	341	$ (196,043)
Issuance of common stock from treasury, shares					43,000
Issuance of common stock from treasury		321			$ 654
Purchase of treasury shares, shares					(1,000)
Purchase of treasury shares					$ (12)
Restricted share award, shares					28,000
Restricted share award		(426)			$ 426
Stock-based compensation		4,789
Cumulative translation adjustments				(72)		(72)
Net loss			(1,023)			(1,023)
Ending balance, shares at Aug. 31, 2019	27,056,000				13,087,000
Ending balance at Aug. 31, 2019	$ 1,353	215,964	59,403	269	$ (194,975)	$ 82,014
Cumulative effect of new accounting principle			(3,143)
Issuance of common stock from treasury, shares					291,000	311,452
Issuance of common stock from treasury		(3,138)			$ 4,184
Purchase of treasury shares, shares					(400,000)	(5,000)
Purchase of treasury shares					$ (13,971)
Restricted share award, shares					21,000
Restricted share award		(333)			$ 333
Stock-based compensation		(573)
Cumulative translation adjustments				372		$ 372
Net loss			(9,435)			(9,435)
Ending balance, shares at Aug. 31, 2020	27,056,000				(13,175,000)
Ending balance at Aug. 31, 2020	$ 1,353	$ 211,920	$ 49,968	$ 641	$ (204,429)	$ 59,453