Condensed Consolidating Statements of Earnings and Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2018	May 31, 2017
Condensed Financial Statements, Captions [Line Items]
Net sales	$ 317,096	$ 295,427	$ 881,216	$ 820,089
Cost of products sold	200,587	192,623	574,100	536,892
Gross profit	116,509	102,804	307,116	283,197
Selling, administrative and engineering expenses	77,570	70,051	220,550	205,609
Amortization of intangible assets	5,184	5,037	15,483	15,368
Restructuring charges	1,170	384	11,249	5,433
Impairment & divestiture charges		0	2,987	0
Director & officer transition charges	0	0	0	7,784
Operating profit	32,585	27,332	56,847	49,003
Financing costs, net	7,756	7,553	22,874	22,019
Intercompany Expense (Income) Net	0	0	0	0
Intercompany Dividends		0		0
Other (income) expense, net	(188)	1,297	508	1,260
Earnings before income tax (benefit) expense	25,017	18,482	33,465	25,724
Income tax (benefit) expense	(3,995)	(4,029)	17,448	(6,827)
Net earnings (loss) before equity in earnings of subsidiaries	29,012	22,511	16,017	32,551
Equity In Earnings Of Subsidiaries	0	0	0	0
Net earnings	29,012	22,511	16,017	32,551
Comprehensive income	8,059	42,835	79,098	29,864
Reportable Legal Entities | Parent
Condensed Financial Statements, Captions [Line Items]
Net sales	41,851	39,753	113,780	106,435
Cost of products sold	6,394	9,944	19,205	27,087
Gross profit	35,457	29,809	94,575	79,348
Selling, administrative and engineering expenses	22,480	18,113	60,385	54,633
Amortization of intangible assets	318	318	954	954
Restructuring charges	661	99	6,211	826
Impairment & divestiture charges			4,217
Director & officer transition charges				7,784
Operating profit	11,998	11,279	22,808	15,151
Financing costs, net	7,847	7,558	23,247	22,314
Intercompany Expense (Income) Net	(2,023)	(3,941)	(11,942)	(16,891)
Intercompany Dividends		5,353		5,353
Other (income) expense, net	(251)	(159)	(211)	1,878
Earnings before income tax (benefit) expense	6,425	2,468	11,714	2,497
Income tax (benefit) expense	(11,354)	(3,521)	(1,027)	(6,084)
Net earnings (loss) before equity in earnings of subsidiaries	17,779	5,989	12,741	8,581
Equity In Earnings Of Subsidiaries	11,233	16,523	3,276	23,970
Net earnings	29,012	22,511	16,017	32,551
Comprehensive income	8,059	42,835	79,098	29,864
Reportable Legal Entities | Guarantors
Condensed Financial Statements, Captions [Line Items]
Net sales	101,780	98,391	272,686	263,640
Cost of products sold	73,266	71,565	201,819	194,802
Gross profit	28,514	26,826	70,867	68,838
Selling, administrative and engineering expenses	18,439	18,060	54,119	51,245
Amortization of intangible assets	2,861	2,865	8,583	8,859
Restructuring charges	253	153	1,331	1,317
Impairment & divestiture charges			0
Director & officer transition charges				0
Operating profit	6,961	5,748	6,834	7,417
Financing costs, net	22	0	65	0
Intercompany Expense (Income) Net	7,120	3,958	18,023	14,114
Intercompany Dividends		0		(59,401)
Other (income) expense, net	(8)	98	86	24
Earnings before income tax (benefit) expense	(173)	1,692	(11,340)	52,680
Income tax (benefit) expense	(86)	(168)	(1,883)	(865)
Net earnings (loss) before equity in earnings of subsidiaries	(87)	1,860	(9,457)	53,545
Equity In Earnings Of Subsidiaries	13,406	15,475	12,745	29,157
Net earnings	13,319	17,335	3,288	82,702
Comprehensive income	13,319	24,376	3,288	71,992
Reportable Legal Entities | Non-Guarantors
Condensed Financial Statements, Captions [Line Items]
Net sales	173,465	157,283	494,750	450,014
Cost of products sold	120,927	111,114	353,076	315,003
Gross profit	52,538	46,169	141,674	135,011
Selling, administrative and engineering expenses	36,651	33,878	106,046	99,731
Amortization of intangible assets	2,005	1,854	5,946	5,555
Restructuring charges	256	132	3,707	3,290
Impairment & divestiture charges			(1,230)
Director & officer transition charges				0
Operating profit	13,626	10,305	27,205	26,435
Financing costs, net	(113)	(5)	(438)	(295)
Intercompany Expense (Income) Net	(5,097)	(17)	(6,081)	2,777
Intercompany Dividends		(5,353)		(5,353)
Other (income) expense, net	71	1,358	633	(642)
Earnings before income tax (benefit) expense	18,765	14,322	33,091	29,948
Income tax (benefit) expense	7,445	(340)	20,358	122
Net earnings (loss) before equity in earnings of subsidiaries	11,320	14,662	12,733	29,826
Equity In Earnings Of Subsidiaries	1,157	1,754	(348)	4,616
Net earnings	12,477	16,416	12,385	34,442
Comprehensive income	(9,092)	28,358	77,294	41,817
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net sales	0	0	0	0
Cost of products sold	0	0	0	0
Gross profit	0	0	0	0
Selling, administrative and engineering expenses	0	0	0	0
Amortization of intangible assets	0	0	0	0
Restructuring charges	0	0	0	0
Impairment & divestiture charges			0
Director & officer transition charges				0
Operating profit	0	0	0	0
Financing costs, net	0	0	0	0
Intercompany Expense (Income) Net	0	0	0	0
Intercompany Dividends		0		59,401
Other (income) expense, net	0	0	0	0
Earnings before income tax (benefit) expense	0	0	0	(59,401)
Income tax (benefit) expense	0	0	0	0
Net earnings (loss) before equity in earnings of subsidiaries	0	0	0	(59,401)
Equity In Earnings Of Subsidiaries	(25,796)	(33,752)	(15,673)	(57,743)
Net earnings	(25,796)	(33,752)	(15,673)	(117,144)
Comprehensive income	$ (4,227)	$ (52,734)	$ (80,582)	$ (113,809)