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, 2020	$ 20	$ 157,850	$ 398,731	$ (28,208)	$ (368,080)	$ 160,313
Beginning balance, shares at Aug. 31, 2020	19,812,685				6,147,899
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes		(3,490)				(3,490)
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes, shares	23,417
Stock-based compensation		2,665				2,665
Cash dividends			(9,199)			(9,199)
Foreign currency translation adjustment				588		588
Net income			23,623			23,623
Ending balance at Nov. 30, 2020	$ 20	157,025	413,155	(27,620)	$ (368,080)	174,500
Ending balance, shares at Nov. 30, 2020	19,836,102				6,147,899
Beginning balance at Aug. 31, 2020	$ 20	157,850	398,731	(28,208)	$ (368,080)	160,313
Beginning balance, shares at Aug. 31, 2020	19,812,685				6,147,899
Foreign currency translation adjustment						4,430
Net income						61,820
Ending balance at May. 31, 2021	$ 20	162,240	432,230	(23,778)	$ (368,080)	202,632
Ending balance, shares at May. 31, 2021	19,855,666				6,147,899
Beginning balance at Nov. 30, 2020	$ 20	157,025	413,155	(27,620)	$ (368,080)	174,500
Beginning balance, shares at Nov. 30, 2020	19,836,102				6,147,899
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes		(5)				(5)
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes, shares	19,564
Stock-based compensation		1,877				1,877
Cash dividends			(9,217)			(9,217)
Foreign currency translation adjustment				3,234		3,234
Net income			17,191			17,191
Ending balance at Feb. 28, 2021	$ 20	158,897	421,129	(24,386)	$ (368,080)	187,580
Ending balance, shares at Feb. 28, 2021	19,855,666				6,147,899
Stock-based compensation		3,343				3,343
Cash dividends			(9,905)			(9,905)
Foreign currency translation adjustment				608		608
Net income			21,006			21,006
Ending balance at May. 31, 2021	$ 20	162,240	432,230	(23,778)	$ (368,080)	202,632
Ending balance, shares at May. 31, 2021	19,855,666				6,147,899
Beginning balance at Aug. 31, 2021	$ 20	163,737	430,735	(26,030)	$ (368,080)	$ 200,382
Beginning balance, shares at Aug. 31, 2021	19,856,865				6,147,899	13,708,966
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes		(4,246)				$ (4,246)
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes, shares	30,072
Stock-based compensation		2,891				2,891
Cash dividends			(9,905)			(9,905)
Acquisition of treasury stock					$ (7,386)	(7,386)
Acquisition of treasury stock, shares					32,000
Foreign currency translation adjustment				(1,893)		(1,893)
Net income			18,555			18,555
Ending balance at Nov. 30, 2021	$ 20	162,382	439,385	(27,923)	$ (375,466)	198,398
Ending balance, shares at Nov. 30, 2021	19,886,937				6,179,899
Beginning balance at Aug. 31, 2021	$ 20	163,737	430,735	(26,030)	$ (368,080)	$ 200,382
Beginning balance, shares at Aug. 31, 2021	19,856,865				6,147,899	13,708,966
Foreign currency translation adjustment						$ (5,412)
Net income						52,543
Ending balance at May. 31, 2022	$ 20	165,159	451,962	(31,442)	$ (390,470)	$ 195,229
Ending balance, shares at May. 31, 2022	19,887,577				6,249,736	13,637,841
Beginning balance at Nov. 30, 2021	$ 20	162,382	439,385	(27,923)	$ (375,466)	$ 198,398
Beginning balance, shares at Nov. 30, 2021	19,886,937				6,179,899
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes		(75)				(75)
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes, shares	579
Stock-based compensation		1,885				1,885
Cash dividends			(10,714)			(10,714)
Acquisition of treasury stock					$ (10,779)	(10,779)
Acquisition of treasury stock, shares					46,637
Foreign currency translation adjustment				627		627
Net income			19,508			19,508
Ending balance at Feb. 28, 2022	$ 20	164,192	448,179	(27,296)	$ (386,245)	198,850
Ending balance, shares at Feb. 28, 2022	19,887,516				6,226,536
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes		(8)				(8)
Issuance of common stock under share-based compensation plan, net of shares withheld for taxes, shares	61
Stock-based compensation		975				975
Cash dividends			(10,697)			(10,697)
Acquisition of treasury stock					$ (4,225)	(4,225)
Acquisition of treasury stock, shares					23,200
Foreign currency translation adjustment				(4,146)		(4,146)
Net income			14,480			14,480
Ending balance at May. 31, 2022	$ 20	$ 165,159	$ 451,962	$ (31,442)	$ (390,470)	$ 195,229
Ending balance, shares at May. 31, 2022	19,887,577				6,249,736	13,637,841