Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Capital In Excess Of Stated Value [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss, Net [Member]
Beginning balance, value at Aug. 31, 2022	$ 393,358	$ 19,063	$ (277,238)	$ 94,006	$ 579,000	$ (21,473)
Beginning balance, shares at Aug. 31, 2022		19,063	8,083
Net earnings	53,150	$ 0	$ 0	0	53,150	0
Other comprehensive income (loss)	(1,134)	0	0	0	0	(1,134)
Total comprehensive income	52,016	0	0	0	0	0
Cash dividends per share	(11,228)	0	0	0	(11,228)	0
Repurchase of common stock	0	0	0	0	0	0
Issuance of common shares under share compensation plans, net	(2,125)	$ 29	$ 0	(2,154)	0	0
Issuance of common shares under share compensation plans, net, shares		29	0
Share-based compensation expense	4,775	$ 0	$ 0	4,775	0	0
Ending balance, value at May. 31, 2023	436,796	$ 19,092	$ (277,238)	96,627	620,922	(22,607)
Ending Balance, shares at May. 31, 2023		19,092	8,083
Beginning balance, value at Feb. 28, 2023	422,272	$ 19,091	$ (277,238)	94,834	607,784	(22,199)
Beginning balance, shares at Feb. 28, 2023		19,091	8,083
Net earnings	16,881	$ 0	$ 0	0	16,881	0
Other comprehensive income (loss)	(408)	0	0	0	0	(408)
Total comprehensive income	16,473	0	0	0	0	0
Cash dividends per share	(3,743)	0	0	0	(3,743)	0
Repurchase of common stock	0	0	0	0	0	0
Issuance of common shares under share compensation plans, net	107	$ 1	$ 0	106	0	0
Issuance of common shares under share compensation plans, net, shares		1	0
Share-based compensation expense	1,687		$ 0	1,687	0	0
Ending balance, value at May. 31, 2023	436,796	$ 19,092	$ (277,238)	96,627	620,922	(22,607)
Ending Balance, shares at May. 31, 2023		19,092	8,083
Beginning balance, value at Aug. 31, 2023	455,651	$ 19,094	$ (277,238)	98,508	636,297	(21,010)
Beginning balance, shares at Aug. 31, 2023		19,094	8,083
Net earnings	53,521	$ 0	$ 0	0	53,521	0
Other comprehensive income (loss)	(3,992)	0	0	0	0	(3,992)
Total comprehensive income	49,529	0	0	0	0	0
Cash dividends per share	(11,557)	0	0	0	(11,557)	0
Repurchase of common stock	(17,900)	$ 0	$ (17,900)	0	0	0
Repurchase of common stock, shares		0	154
Issuance of common shares under share compensation plans, net	(614)	$ 29	$ 0	(643)	0	0
Issuance of common shares under share compensation plans, net, shares		29	0
Share-based compensation expense	4,887	$ 0	$ 0	4,887	0	0
Ending balance, value at May. 31, 2024	479,996	$ 19,123	$ (295,138)	102,752	678,261	(25,002)
Ending Balance, shares at May. 31, 2024		19,123	8,237
Beginning balance, value at Feb. 29, 2024	483,034	$ 19,122	$ (277,238)	101,060	661,715	(21,625)
Beginning balance, shares at Feb. 29, 2024		19,122	8,083
Net earnings	20,379	$ 0	$ 0	0	20,379	0
Other comprehensive income (loss)	(3,377)	0	0	0	0	(3,377)
Total comprehensive income	17,002	0	0	0	0
Cash dividends per share	(3,833)	$ 0	0	0	(3,833)	0
Repurchase of common stock	(17,900)		$ (17,900)
Repurchase of common stock, shares		0	154
Issuance of common shares under share compensation plans, net	141	$ 1	$ 0	140	0	0
Issuance of common shares under share compensation plans, net, shares		1	0
Share-based compensation expense	1,552		$ 0	1,552	0	0
Ending balance, value at May. 31, 2024	$ 479,996	$ 19,123	$ (295,138)	$ 102,752	$ 678,261	$ (25,002)
Ending Balance, shares at May. 31, 2024		19,123	8,237