CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Beginning balance at Aug. 31, 2018	$ 20	$ 153,469	$ 351,266	$ (27,636)	$ (321,630)	$ 155,489
Beginning balance, shares at Aug. 31, 2018	19,729,774				5,879,361
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes		(2,425)				(2,425)
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes, shares	24,062
Stock-based compensation		1,965				1,965
Cash dividends			(7,522)			(7,522)
Acquisition of treasury stock					$ (6,863)	(6,863)
Acquisition of treasury stock, shares					41,184
Foreign currency translation adjustment				(1,631)		(1,631)
Net income			13,279			13,279
Ending balance at Nov. 30, 2018	$ 20	153,009	356,699	(29,267)	$ (328,493)	151,968
Ending balance, shares at Nov. 30, 2018	19,753,836				5,920,545
Cumulative effect of change in accounting principle			(324)			(324)
Beginning balance at Aug. 31, 2019	$ 20	155,132	374,060	(32,482)	$ (351,255)	$ 145,475
Beginning balance, shares at Aug. 31, 2019	19,773,977				6,055,316	13,718,661
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes		(2,640)				$ (2,640)
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes, shares	22,342
Stock-based compensation		2,214				2,214
Cash dividends			(8,406)			(8,406)
Acquisition of treasury stock					$ (4,957)	(4,957)
Acquisition of treasury stock, shares					26,800
Foreign currency translation adjustment				2,112		2,112
Net income			12,194			12,194
Ending balance at Nov. 30, 2019	$ 20	$ 154,706	$ 377,848	$ (30,370)	$ (356,212)	$ 145,992
Ending balance, shares at Nov. 30, 2019	19,796,319				6,082,116	13,714,203