Business Segments (Details) $ in Thousands		3 Months Ended		9 Months Ended
	Oct. 29, 2018 segment	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)	Oct. 01, 2019 USD ($)	Sep. 30, 2019 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment	3	2		2
Segment Reporting Information [Line Items]
Revenue from product sales and services		$ 347,827	$ 360,343	$ 1,045,595	$ 1,031,973
Operating profit (loss)		33,066	27,091	123,913	32,200
Interest expense		(10,485)	(14,842)	(37,320)	(43,759)
Income (loss) before income taxes		22,581	12,249	86,593	(11,559)
Income tax (expense) benefit		(740)	(7,959)	(3,336)	1,134
Net income (loss)		21,841	4,290	83,257	(10,425)
Depreciation and amortization		27,542	24,145	80,056	71,397
Capital expenditures		27,165	23,266	65,924	63,948
Assets		1,777,896		1,777,896		$ 1,782,660	$ 1,737,848
Goodwill		393,427		393,427			392,890
Integrated Solutions and Services
Segment Reporting Information [Line Items]
Revenue from product sales and services		228,711	225,429	694,734
Capital expenditures		23,734	19,646	56,918	53,303
Applied Product Technologies
Segment Reporting Information [Line Items]
Revenue from product sales and services		119,116	134,914	350,861
Capital expenditures		1,040	1,720	4,407	5,988
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue from product sales and services		18,837	25,998	61,646	74,254
Intersegment Eliminations | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Revenue from product sales and services		1,603	2,386	8,204	6,240
Intersegment Eliminations | Applied Product Technologies
Segment Reporting Information [Line Items]
Revenue from product sales and services		17,234	23,612	53,442	68,014
Operating Segments
Segment Reporting Information [Line Items]
Total sales		366,664	386,341	1,107,241	1,106,227
Operating Segments | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Total sales		230,314	227,815	702,938	669,031
Revenue from product sales and services		228,711	225,429	694,734	662,791
Operating profit (loss)		32,608	37,345	102,457	102,282
Depreciation and amortization		17,745	14,035	50,702	42,307
Assets		836,389		836,389			762,707
Goodwill		222,669		222,669			222,013
Operating Segments | Applied Product Technologies
Segment Reporting Information [Line Items]
Total sales		136,350	158,526	404,303	437,196
Revenue from product sales and services		119,116	134,914	350,861	369,182
Operating profit (loss)		23,588	22,524	110,480	38,362
Depreciation and amortization		3,556	4,350	10,673	13,142
Assets		589,721		589,721			657,879
Goodwill		170,758		170,758			170,877
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Operating profit (loss)		(23,130)	(32,778)	(89,024)	(108,444)
Depreciation and amortization		6,241	5,760	18,681	15,948
Capital expenditures		2,391	$ 1,900	4,599	$ 4,657
Assets		$ 351,786		$ 351,786			$ 317,262