Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		$ 346,564	$ 351,663	$ 668,757	$ 697,768
Operating Leases, Income Statement, Lease Revenue	[1]	48,645	36,669	85,650	74,172
United States
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		274,681	290,273	538,812	567,990
Europe
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		31,527	30,381	52,812	56,493
Asia
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		26,976	12,720	49,581	31,462
Canada
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		10,636	16,319	21,815	33,882
Australia
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		2,744	1,970	5,737	7,941
Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		224,134	237,885	438,851	466,023
Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		122,430	113,778	229,906	231,745
Revenue from aftermarket
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		60,077	64,663	112,577	131,677
Revenue from aftermarket | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		32,501	31,901	59,647	61,574
Revenue from aftermarket | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		27,576	32,762	52,930	70,103
Revenue from service
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		144,098	145,694	286,276	295,239
Revenue from service | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		139,540	139,892	276,485	283,737
Revenue from service | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		4,558	5,802	9,791	11,502
Revenue from capital projects
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		142,389	141,306	269,904	270,852
Revenue from capital projects | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		52,093	66,092	102,719	120,712
Revenue from capital projects | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		90,296	75,214	167,185	150,140
Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		$ 297,919	$ 314,994	$ 583,107	$ 623,596

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