Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands		3 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		$ 322,193	$ 346,105
Operating Leases, Income Statement, Lease Revenue	[1]	37,005	37,503
United States
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		264,131	277,717
Europe
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		21,285	26,112
Asia
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		22,605	18,742
Canada
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		11,179	17,563
Australia
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		2,993	5,971
Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		214,717	228,138
Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		107,476	117,967
Revenue from aftermarket
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		52,500	67,014
Revenue from aftermarket | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		27,146	29,673
Revenue from aftermarket | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		25,354	37,341
Revenue from service
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		142,178	149,545
Revenue from service | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		136,945	143,845
Revenue from service | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		5,233	5,700
Revenue from capital projects
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		127,515	129,546
Revenue from capital projects | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		50,626	54,620
Revenue from capital projects | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		76,889	74,926
Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		$ 285,188	$ 308,602

[1] Other revenue relates to revenue recognized pursuant to ASU 2016-02, Leases (Topic 842), mainly attributable to long term rentals.