Financial Information from Continuing Operations By Geographic Region (Detail) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2022	Aug. 31, 2021	Aug. 31, 2020
Geographic Reporting Disclosure [Line Items]
Percentage Of Export Sales From Domestic To Total Net Sales	9.80%	7.20%	7.30%
Assets	$ 757,312	$ 820,247
Net sales	$ 571,223	$ 528,660	$ 493,292
Largest customer sales in fiscal year, percent	3.00%	3.00%	3.00%
Property, plant & equipment, net	$ 41,372	$ 48,590
United States
Geographic Reporting Disclosure [Line Items]
Net sales	226,020	188,070	$ 185,279
Property, plant & equipment, net	16,743	18,942
GERMANY
Geographic Reporting Disclosure [Line Items]
Net sales	28,004	28,456	24,401
UNITED KINGDOM
Geographic Reporting Disclosure [Line Items]
Net sales	29,316	39,896	24,033
Property, plant & equipment, net	8,212	11,818
SAUDI ARABIA
Geographic Reporting Disclosure [Line Items]
Net sales	20,892	16,715	19,787
AUSTRALIA
Geographic Reporting Disclosure [Line Items]
Net sales	26,667	24,990	19,332
BRAZIL
Geographic Reporting Disclosure [Line Items]
Net sales	16,517	13,937	16,413
Property, plant & equipment, net	2,873	2,248
CANADA
Geographic Reporting Disclosure [Line Items]
Net sales	19,651	17,348	15,924
China
Geographic Reporting Disclosure [Line Items]
Net sales	15,434	16,927	15,058
UNITED ARAB EMIRATES
Geographic Reporting Disclosure [Line Items]
Property, plant & equipment, net	4,407	6,448
NETHERLANDS
Geographic Reporting Disclosure [Line Items]
Property, plant & equipment, net	1,965	2,625
KAZAKHSTAN
Geographic Reporting Disclosure [Line Items]
Property, plant & equipment, net	1,028	1,552
SPAIN
Geographic Reporting Disclosure [Line Items]
Property, plant & equipment, net	1,413	1,506
All Other
Geographic Reporting Disclosure [Line Items]
Net sales	188,722	182,321	$ 173,065
Property, plant & equipment, net	4,731	3,451
General Corporate
Geographic Reporting Disclosure [Line Items]
Assets	$ 92,472	$ 126,246