Business Segments (Details) $ in Thousands		3 Months Ended
	Oct. 29, 2018 segment	Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Sep. 30, 2020 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment	3	2
Segment Reporting Information [Line Items]
Revenue from product sales and services		$ 322,193	$ 346,105
Operating profit (loss)		16,234	69,692
Interest expense		(8,673)	(13,583)
Income (loss) before income taxes		7,561	56,109
Income tax (expense) benefit		(1,084)	(2,603)
Net income		6,477	53,506
Depreciation and amortization		27,391	25,143
Capital expenditures		17,260	17,572
Assets		1,843,666		$ 1,844,458
Goodwill		408,593		397,205
Integrated Solutions and Services
Segment Reporting Information [Line Items]
Revenue from product sales and services		214,717	228,138
Applied Product Technologies
Segment Reporting Information [Line Items]
Revenue from product sales and services		107,476	117,967
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue from product sales and services		18,141	24,224
Intersegment Eliminations | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Revenue from product sales and services		2,036	3,662
Intersegment Eliminations | Applied Product Technologies
Segment Reporting Information [Line Items]
Revenue from product sales and services		16,105	20,562
Operating Segments
Segment Reporting Information [Line Items]
Total sales		340,334	370,329
Operating Segments | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Total sales		216,753	231,800
Revenue from product sales and services		214,717
Operating profit (loss)		26,357	33,154
Assets		846,707		835,307
Goodwill		232,531		224,381
Operating Segments | Applied Product Technologies
Segment Reporting Information [Line Items]
Total sales		123,581	138,529
Revenue from product sales and services		107,476
Operating profit (loss)		13,380	63,142
Assets		599,543		598,701
Goodwill		176,062		172,824
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Operating profit (loss)		(23,503)	$ (26,604)
Assets		$ 397,416		$ 410,450