Evoqua Water Technologies (AQUA) 10-K 16 Nov 22 2022 FY Annual report Financial data

Cover

Cover - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022	Oct. 31, 2022	Mar. 31, 2022	Sep. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Sep. 30, 2022
Document Transition Report	false
Entity File Number	001-38272
Entity Registrant Name	EVOQUA WATER TECHNOLOGIES CORP.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-4132761
Entity Address, Address Line One	210 Sixth Avenue
Entity Address, City or Town	Pittsburgh,
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	15222
City Area Code	724
Local Phone Number	772-0044
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	AQUA
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Common stock, par value (in USD per share)	$ 0.01			$ 0.01
Entity Public Float			$ 5,600
Entity Common Stock, Shares Outstanding		121,812,049
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement (the “Proxy Statement”) for its annual meeting of shareholders to be held in February 2023, are incorporated by reference into Part III of this Report. The Proxy Statement will be filed with the U.S. Securities and Exchange Commission within 120 days after the end of the fiscal year to which this report relates.
Amendment Flag	false
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2022
Entity Central Index Key	0001604643
Current Fiscal Year End Date	--09-30

Audit Information

Audit Information	12 Months Ended
	Sep. 30, 2022
Audit Information [Abstract]
Auditor Name	Ernst & Young LLP
Auditor Location	Pittsburgh, Pennsylvania
Auditor Firm ID	42

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
ASSETS
Current assets	$ 831,389	$ 678,458
Cash and cash equivalents	134,005	146,244
Receivables, net	305,712	277,995
Inventories, net	229,351	158,503
Contract assets	102,123	72,746
Prepaid and other current assets	59,971	21,871
Income tax receivable	227	1,099
Property, plant, and equipment, net	405,289	374,988
Goodwill	473,572	407,376
Intangible assets, net	317,733	290,075
Deferred income taxes, net of valuation allowance	5,841	8,285
Operating Lease, Right-of-Use Asset	53,540	45,521
Other non‑current assets	103,499	64,188
Total assets	2,190,863	1,868,891
LIABILITIES AND EQUITY
Current liabilities	483,716	405,989
Accounts payable	213,518	164,535
Current portion of debt, net of deferred financing fees and discounts	17,266	12,775
Contract liabilities	62,439	55,883
Product warranties	6,740	8,138
Accrued expenses and other liabilities	178,272	160,367
Income tax payable	5,481	4,291
Non‑current liabilities	997,054	880,683
Long‑term debt, net of deferred financing fees and discounts	863,534	730,430
Product warranties	3,465	2,966
Obligations under operating leases, excluding current installments	43,961	37,935
Other non‑current liabilities	69,889	92,909
Deferred income taxes	16,205	16,443
Total liabilities	1,480,770	1,286,672
Commitments and Contingencies
Shareholders’ equity
Common stock	1,235	1,223
Treasury Stock, Value	(2,837)	(2,837)
Additional paid‑in capital	607,748	582,052
Retained earnings (deficit)	61,016	(11,182)
Accumulated other comprehensive income, net of tax	42,931	11,415
Total Evoqua Water Technologies Corp. equity	710,093	580,671
Non‑controlling interest	0	1,548
Total shareholders’ equity	710,093	582,219
Total liabilities and shareholders’ equity	$ 2,190,863	$ 1,868,891

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2022	Sep. 30, 2021
Statement of Financial Position [Abstract]
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares, issued (in shares)	123,411,000	122,173,000
Common stock, outstanding (in shares)	121,747,000	120,509,000
Treasury stock, shares (in shares)	1,664,000	1,664,000

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Revenues [Abstract]
Sales to external customers	$ 1,737,076	$ 1,464,429	$ 1,429,456
Cost of Revenue [Abstract]
Cost of product sales and services	(1,201,097)	(1,007,077)	(979,653)
Gross profit	535,979	457,352	449,803
Operating Expenses [Abstract]
General and administrative expense	(260,550)	(206,455)	(192,597)
Sales and marketing expense	(161,303)	(143,110)	(136,167)
Research and development expense	(15,442)	(13,445)	(13,198)
Total operating expenses	(437,295)	(363,010)	(341,962)
Other operating income	5,726	5,743	61,662
Other operating expense	(417)	(768)	(1,055)
Income before interest expense and income taxes	103,993	99,317	168,448
Interest expense	(34,680)	(37,575)	(46,682)
Income before income taxes	69,313	61,742	121,766
Income tax benefit (expense)	3,030	(10,080)	(7,371)
Net income	72,343	51,662	114,395
Net income attributable to non‑controlling interest	145	180	746
Net income attributable to Evoqua Water Technologies Corp.	$ 72,198	$ 51,482	$ 113,649
Basic income per common share	$ 0.60	$ 0.43	$ 0.97
Diluted income per common share	$ 0.58	$ 0.42	$ 0.94
Product
Revenues [Abstract]
Sales to external customers	$ 1,052,488	$ 861,026	$ 839,857
Cost of Revenue [Abstract]
Cost of product sales and services	(740,464)	(607,693)	(588,264)
Revenue from service
Revenues [Abstract]
Sales to external customers	684,588	603,403	589,599
Cost of Revenue [Abstract]
Cost of product sales and services	$ (460,633)	$ (399,384)	$ (391,389)

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 72,343	$ 51,662	$ 114,395
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation adjustments	(9,370)	21,672	(2,830)
Unrealized derivative gain (loss) on cash flow hedges, net of tax	35,188	7,293	(4,717)
Change in pension liability, net of tax	5,698	2,922	79
Total other comprehensive income (loss)	31,516	31,887	(7,468)
Less: Comprehensive income attributable to non‑controlling interest	(145)	(180)	(746)
Comprehensive income attributable to Evoqua Water Technologies Corp.	$ 103,714	$ 83,369	$ 106,181

Condensed Consolidated Statemen

Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid‑in Capital	Retained Earnings (Deficit)	Accumulated Other Comprehensive (Loss) Income	Noncontrolling Interest	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjustment Retained Earnings (Deficit)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, outstanding (in shares)		116,008,000
Stockholders' equity, balance at the beginning of the period at Sep. 30, 2019	$ 365,822	$ 1,154	$ (2,837)	$ 552,422	$ (174,976)	$ (13,004)	$ 3,063	$ (1,337)	$ (1,337)
Treasury stock, balance at the beginning of the period (shares) at Sep. 30, 2019			1,664,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity based compensation expense	10,509			10,509
Issuance of common stock (shares)		3,478,000	531,000
Issuance of common stock, net	18,927	$ 35		18,892
Dividends paid to non-controlling interest	(1,890)						(1,890)
Divestiture of Memcor product line	(16,895)			(16,895)
Net income	114,395				113,649		746
Other comprehensive loss	(7,468)					(7,468)
Common stock, ending balance (in shares) at Sep. 30, 2020		119,486,000
Stockholders' equity, balance at the end of the period at Sep. 30, 2020	482,063	$ 1,189	$ (2,837)	564,928	(62,664)	(20,472)	1,919
Treasury stock, balance at the end of the period (shares) at Sep. 30, 2020			2,195,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, outstanding (in shares)		119,486,000
Equity based compensation expense	15,524			15,524
Issuance of common stock (shares)		2,687,000	(531,000)
Issuance of common stock, net	1,634	$ 34		1,600
Dividends paid to non-controlling interest	(551)						(551)
Net income	51,662				51,482		180
Other comprehensive loss	$ 31,887					31,887
Common stock, ending balance (in shares) at Sep. 30, 2021	120,509,000	122,173,000
Stockholders' equity, balance at the end of the period at Sep. 30, 2021	$ 582,219	$ 1,223	$ (2,837)	582,052	(11,182)	11,415	1,548
Treasury stock, balance at the end of the period (shares) at Sep. 30, 2021	1,664,000		1,664,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, outstanding (in shares)	120,509,000	122,173,000
Equity based compensation expense				22,104
Issuance of common stock (shares)		1,238,000	0
Issuance of common stock, net	$ 3,604	$ 12		3,592
Dividends paid to non-controlling interest	(100)						(100)
Net income	72,343				72,198		145
Other comprehensive loss	$ 31,516					31,516
Common stock, ending balance (in shares) at Sep. 30, 2022	121,747,000	123,411,000
Stockholders' equity, balance at the end of the period at Sep. 30, 2022	$ 710,093	$ 1,235	$ (2,837)	$ 607,748	$ 61,016	$ 42,931	0
Treasury stock, balance at the end of the period (shares) at Sep. 30, 2022	1,664,000		1,664,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	$ (1,593)						$ (1,593)
Common stock, outstanding (in shares)	121,747,000	123,411,000

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Changes in Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Operating activities
Net income	$ 72,343	$ 51,662	$ 114,395
Reconciliation of net income to cash flows provided by operating activities:
Depreciation and amortization	127,570	113,664	107,268
Amortization of Debt Issuance Costs	1,866	3,280	4,026
Deferred income taxes	(15,018)	(2,363)	(1,234)
Share-based compensation	22,104	15,524	10,509
(Gain) loss on sale of property, plant, and equipment	(1,681)	1,287	950
(Gain) loss on sale of business	(193)	193	(68,051)
Foreign currency exchange losses (gains) on intercompany loans and other non-cash items	18,778	(1,094)	(8,202)
Changes in assets and liabilities
Accounts receivable	(9,821)	(13,281)	(6,844)
Inventories	(42,560)	(15,985)	(7,604)
Contract assets	(30,857)	8,426	(4,136)
Prepaids and other current assets	(13,173)	260	2,088
Accounts payable	43,132	9,824	8,017
Accrued expenses and other liabilities	13,943	21,881	22,078
Contract liabilities	7,497	28,447	(12,556)
Income taxes	2,440	(2,091)	592
Other non‑current assets and liabilities	(14,968)	(40,929)	15,730
Net cash provided by operating activities	181,402	178,705	177,026
Investing activities
Purchase of property, plant, and equipment	(82,045)	(75,293)	(88,456)
Purchase of intangibles	(3,281)	(3,780)	(6,529)
Proceeds from sale of property, plant, and equipment	3,553	2,041	1,191
Proceeds from divestiture	356	897	118,894
Payments to Acquire Businesses, Net of Cash Acquired	(229,277)	(21,037)	(13,108)
Net cash (used in) provided by investing activities	(310,694)	(97,172)	11,992
Financing activities
Issuance of debt, net of deferred issuance costs	263,396	761,915	21,959
Borrowings under credit facility	0	0	2,597
Repayment of debt	(127,667)	(898,024)	(117,131)
Finance Lease, Principal Payments	(13,356)	(13,396)	(13,441)
Payment of earn-out related to previous acquisitions	0	(170)	(470)
Proceeds from issuance of common stock	9,556	21,205	10,091
Taxes paid related to net share settlements of share-based compensation awards	(6,281)	(1,323)	(9,832)
Distribution to non‑controlling interest	(100)	(551)	(1,890)
Net cash provided by (used in) financing activities	125,548	(130,344)	(108,117)
Effect of exchange rate changes on cash	(8,495)	2,054	2,219
Change in cash and cash equivalents	(12,239)	(46,757)	83,120
Cash and cash equivalents
Beginning of period	146,244	193,001	109,881
End of period	134,005	146,244	193,001
Supplemental disclosure of cash flow information
Cash paid for taxes	9,883	14,194	8,427
Cash paid for interest	27,562	26,502	38,680
Non‑cash investing and financing activities
Accrued earn-out related to acquisitions	0	0	204
Finance lease transactions	14,531	14,351	12,600
Operating lease transactions	22,864	12,894	23,727
Option and Purchase Right	$ 0	$ 8,305	$ 7,739

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Changes in Cash Flows (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Statement of Cash Flows [Abstract]
Write off of deferred financing fees	$ 0	$ 1,333	$ 1,795
Cash divested with sale of business	0	0	12,117
Cash acquired from acquisition	$ 411	$ 0	$ 0

Description of the Company and

Description of the Company and Basis of Presentation	12 Months Ended
	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Company and Basis of Presentation	Description of the Company and Basis of Presentation Background Evoqua Water Technologies Corp. (referred to herein as the “Company” or “EWT”) is a holding company and does not conduct any business operations of its own. The Company was incorporated on October 7, 2013. On November 6, 2017, the Company completed its initial public offering (“IPO”). The Business EWT provides a wide range of product brands and advanced water and wastewater treatment systems and technologies, as well as mobile and emergency water supply solutions and service contract options through its branch network. Headquartered in Pittsburgh, Pennsylvania, EWT is a multinational corporation with operations in the United States (“U.S.”), Canada, the United Kingdom (“UK”), the Netherlands, Germany, Australia, the People’s Republic of China, Singapore, and India. The Company is organizationally structured into two reportable operating segments for the purpose of making operational decisions and assessing financial performance: (i) Integrated Solutions and Services and (ii) Applied Product Technologies. Basis of Presentation The accompanying Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) from the accounting records of the Company and reflect the consolidated financial position and results of operations for the fiscal years ended September 30, 2022, 2021 and 2020. Unless otherwise specified, references in this section to a year refer to its fiscal year. All intercompany transactions have been eliminated. Unless otherwise specified, all dollar and share amounts in this section are referred to in thousands. Certain prior period amounts have been reclassified to conform to the current period presentation. The Company’s fiscal year ends on September 30 of each year and references in this section to a year refer to the Company’s fiscal year. As such, references to: 2022 relates to the fiscal year ended September 30, 2022, 2021 relates to the fiscal year ended September 30, 2021 and 2020 relates to the fiscal year ended September 30, 2020.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Fiscal Year The Company’s fiscal year ends on September 30. Use of Estimates The Consolidated Financial Statements have been prepared in conformity with GAAP and require management to make estimates and assumptions. These assumptions affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the audited Consolidated Financial Statements and the reported amounts of revenue and expenses during the reporting period. Estimates and assumptions are used for, but not limited to: (i) revenue recognition; (ii) allowance for credit losses; (iii) inventory valuation, asset valuations, impairment, and recoverability assessments; (iv) depreciable lives of assets; (v) useful lives of intangible assets; (vi) income tax reserves and valuation allowances; and (vii) product warranty and litigation reserves. Estimates are revised as additional information becomes available. Actual results could differ from these estimates. Cash and Cash Equivalents Cash and cash equivalents are liquid investments with an original maturity of three or fewer months when purchased. Accounts Receivable Receivables are primarily comprised of uncollected amounts owed to the Company from transactions with customers and are reported on the Consolidated Balance Sheets at the outstanding principal amount adjusted for any allowance for credit losses and any charge offs. The Company provides an allowance for credit losses to reduce trade receivables to their estimated net realizable value equal to the amount that is expected to be collected. This allowance is estimated based on historical collection experience, the aging of receivables, specific current and expected future macroeconomic and market conditions, and assessments of the current creditworthiness and economic status of customers. The Company considers a receivable delinquent if it is unpaid after the term of the related invoice has expired. Write‑offs are recorded at the time all collection efforts have been exhausted. The Company reviews its allowance for credit losses on a quarterly basis. Inventories Inventories are stated at the lower of cost or net realizable value, where cost is generally determined on the basis of an average or first‑in, first‑out (“FIFO”) method. Production costs comprise direct material and labor and applicable manufacturing overheads, including depreciation charges. The Company regularly reviews inventory quantities on hand and writes off excess or obsolete inventory based on estimated forecasts of product demand and production requirements. Manufacturing operations recognize cost of product sales using standard costing rates with overhead absorption which generally approximates actual cost. Property, Plant, and Equipment Property, plant, and equipment is valued at cost less accumulated depreciation. Depreciation expense is recognized using the straight‑line method. Useful lives are reviewed annually and, if expectations differ from previous estimates, adjusted accordingly. Estimated useful lives for major classes of depreciable assets are as follows: Asset Class Estimated Useful Life Machinery and equipment 3 to 20 years Buildings and improvements 10 to 40 years Leasehold improvements are depreciated over the shorter of their estimated useful life or the term of the lease. Costs related to maintenance and repairs that do not extend the assets’ useful life are expensed as incurred. Acquisitions The Company evaluates the inputs, processes and outputs of each asset acquired to determine if the transaction meets the definition of a business in accordance with Accounting Standards Codification (“ASC”) Topic No. 805, Business Combinations (“ASC 805”). Acquisitions that do not meet the definition of a business are accounted for as an asset acquisition. In asset acquisitions, the Company allocates the purchase price as well as other costs of acquisition, such as transaction costs, to tangible and identifiable intangible assets or liabilities based on the basis of relative fair values. This cost accumulation model is unique to asset acquisitions and differs from business combinations as there is no goodwill recognized. Acquisitions that meet the definition of a business are recorded using the acquisition method of accounting. The purchase price of acquisitions is allocated to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair value at the acquisition date. The excess of the acquisition price over those estimated fair values is recorded as goodwill. Changes to the acquisition date preliminary fair values prior to the expiration of the measurement period, a period not to exceed 12 months from date of acquisition, are recorded as an adjustment to the associated goodwill. Contingent consideration resulting from acquisitions is recorded at its estimated fair value on the acquisition date. These obligations are revalued during each subsequent reporting period and changes in the fair value of the contingent consideration obligations can result from adjustments in the probability of achieving future development steps, sales targets and profitability and are recorded in General and administrative expenses in the Consolidated Statements of Operations. Acquisition-related expenses and restructuring costs, if any, are recognized separately from the business combination and are expensed as incurred. Goodwill and Intangible Assets Goodwill represents purchase consideration paid in a business combination that exceeds the value assigned to the net assets of acquired businesses. Intangible assets consist of customer‑related intangibles, proprietary technology, software, trademarks, and other intangible assets. The Company amortizes intangible assets with definite useful lives on a straight‑line basis over their respective estimated economic lives which range from 1 to 26 years. The Company reviews goodwill and indefinite-lived intangible assets to determine potential impairment annually during the fourth quarter of its fiscal year, or more frequently if events and circumstances indicate that the asset might be impaired. Impairment testing for goodwill is performed at a reporting unit level and the Company has determined that it has three reporting units. The quantitative impairment testing for goodwill utilizes both a market (guideline public company) and income (discounted cash flows) method for determining fair value. In estimating the fair value of the reporting unit utilizing a discounted cash flow (“DCF”) valuation technique, the Company incorporates its judgment and estimates of future cash flows, future revenue and gross profit growth rates, terminal value amount, capital expenditures and applicable weighted‑average cost of capital used to discount these estimated cash flows. The estimates and projections used in the estimate of fair value are consistent with the Company’s current budget and long‑range plans, including anticipated change in market conditions, industry trend, growth rates and planned capital expenditures, among other considerations. The impairment test for indefinite-lived intangibles consists of a comparison of the asset’s fair value with its carrying value. The fair value is calculated using the income approach DCF method. Impairment is determined to exist when the fair value is less than the carrying value of the assets being tested. Impairment of Long‑Lived Assets Long‑lived assets, such as property, plant, and equipment, purchased intangibles and lease right-of-use assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. Recoverability of the asset or asset group is measured by comparison of its carrying amount to undiscounted future net cash flows the asset or asset group is expected to generate. If the carrying amount of an asset or asset group is not recoverable, the Company recognizes an impairment loss based on the excess of the carrying amount of the asset or asset group over its respective fair value which is generally determined as the present value of estimated future cash flows or as the appraised value. Debt Issuance Costs and Debt Discounts Debt issuance costs are capitalized and amortized over the contractual term of the underlying debt using the effective interest method. Debt discounts and lender arrangement fees deducted from the proceeds have been included as a component of the carrying value of debt and are being amortized to interest expense using the effective interest method. Revenue Recognition The Company recognizes sales of products and services based on the five-step analysis of transactions as provided in Topic 606, Revenue from Contracts with Customers. For sales of aftermarket parts or products with a low level of customization and engineering time, the Company recognizes revenue at the time risks and rewards of ownership pass, which is generally when products are shipped or delivered to the customer as the Company has no obligation for installation. The Company considers shipping and handling services to be fulfillment activities and as such they do not represent separate performance obligations for revenue recognition. Sales of short‑term service arrangements are recognized as the services are performed, and sales of long‑term service arrangements are typically recognized on a straight‑line basis over the life of the agreement. For certain arrangements where there is significant customization to the product and for long-term construction-type sales contracts, revenue may be recognized over time. These arrangements include large capital water treatment projects, systems, and solutions for municipal and industrial applications. The nature of the contracts is generally fixed price with milestone billings. Contract revenue and cost estimates are reviewed and revised quarterly at a minimum and the cumulative effect of such adjustments are recognized in current operations. The amount of such adjustments has not been material. Contract assets relate to costs incurred to perform in advance of scheduled billings. Contract liabilities relate to payments received in advance of performance under the contracts. Change in contract assets and liabilities are due to the Company’s performance under the contract. The Company has made accounting policy elections to exclude all taxes by governmental authorities from the measurement of the transaction price and that long-term construction-type sales contracts, or those contracts for products with significant customization that the total contract price is less than $100 will be recorded at the point in time when the construction is complete. The recording of assets recognized from the costs to obtain and fulfill customer contracts primarily relate to the deferral of sales commissions. The Company’s costs incurred to obtain or fulfill a contract with a customer are classified as non-current assets and amortized to expense over the period of benefit of the related revenue. These costs are recorded within Cost of product sales and services. The amount of contract costs was insignificant at September 30, 2022. The Company offers standard warranties that generally do not represent a separate performance obligation. In certain instances, a warranty is obtained separately from the original equipment sale or the warranty provides incremental services and as such is treated as a separate performance obligation. Variable consideration in contracts for the years ended September 30, 2022 and 2021 was insignificant. Product Warranties Accruals for estimated expenses related to warranties are made at the time products are sold and are recorded as a component of Cost of product sales in the Consolidated Statements of Operations. The estimated warranty obligation is based on product warranty terms offered to customers, ongoing product failure rates, material usage and service delivery costs expected to be incurred in correcting a product failure, as well as specific obligations for known failures and other currently available evidence. The Company assesses the adequacy of the recorded warranty liabilities on a regular basis and adjusts amounts as necessary. The Company accrues warranty obligations associated with certain products as revenue is recognized. Provisions for the warranty obligations are based upon historical experience of costs incurred for such obligations, adjusted for site‑specific risk factors, and, as necessary, for current conditions and factors. There are significant uncertainties and judgments involved in estimating warranty obligations, including changing product designs, differences in customer installation processes and future claims experience which may vary from historical claims experience. Leases The Company accounts for leases in accordance with ASC Topic No. 842, Leases . Lessee Accounting The Company leases office space, buildings, vehicles, forklifts, computers, copiers and other assets under non-cancelable operating and finance leases. The Company determines whether an arrangement is or contains a lease at the inception of the arrangement based on the terms and conditions in the contract. A contract contains a lease if there is an identified asset and the Company has the right to control the asset. If the arrangement contains a lease, the Company recognizes a right-of-use (“ROU”) asset and an operating lease liability as of the lease commencement date. Any lease arrangements with a term of 12 months or less are not recorded on the Consolidated Balance Sheets, and lease costs for these arrangements are recognized on a straight-line basis over the lease term. Many of the Company’s lease arrangements provide for an option to exercise one or more renewal terms or to terminate the lease arrangement. The Company includes these options when the Company is reasonably certain to exercise them in the leased term used to establish the ROU asset and lease liabilities. The discount rate utilized in calculating the lease liability is the rate implicit in the lease, if known, otherwise, the incremental borrowing rate (“IBR”) for the expected lease term is used. Operating lease assets and finance lease assets are included in Operating lease right-of-use assets, net and Property, plant, and equipment, net, respectively, on the Consolidated Balance Sheets. The corresponding operating lease liabilities are included in Accrued expenses and other liabilities and Obligation under operating leases on the Consolidated Balance Sheets. The corresponding finance lease liabilities are included in Accrued expenses and other liabilities and Other non‑current liabilities on the Consolidated Balance Sheets. Lessor Accounting The Company generates revenue through the lease of its water treatment equipment and systems to customers. In certain instances, the Company enters into a contract with a customer but must construct the underlying asset prior to its lease. At the time of contract inception, the Company determines if an arrangement is or contains a lease. These contracts generally contain both lease and non-lease components, including installation, maintenance, and monitoring services of the Company-owned equipment, in addition to sale of certain constructed assets. In situations where arrangements contain multiple elements, contract consideration is allocated based on relative standalone selling price. Lease components associated with underlying assets that have an alternative use are classified as operating leases with revenue recognized over time throughout the lease term. Lease components associated with underlying assets that have no alternative are classified as sales-type leases, with point in time revenue recognition at the on-set of the lease, or classified as financing transactions, with over time revenue recognition at the on-set of the construction of the underlying assets. In order for a component to be separate, the customer would be able to benefit from the right of use of the component separately or with other resources readily available to the customer and the right of the use is not highly dependent or highly interrelated with the other rights to use the other underlying assets or components. Shipping and Handling Cost Shipping and handling costs are included as a component of Cost of product sales. Derivative Financial Instruments The Company’s risk-management strategy uses derivative financial instruments to manage interest rate risk, foreign currency exchange rate risk, equity price risk and commodity price risk. The Company does not enter into derivatives for trading or speculative purposes. The Company accounts for derivatives and hedging activities in accordance with ASC Topic No. 815, Derivatives and Hedging (“Topic No. 815”). As required by Topic No. 815, the Company records all derivatives on the Consolidated Balance Sheets at fair value and adjusts to market on a quarterly basis. Changes in the fair value of derivatives are recorded in earnings or Accumulated other comprehensive income, net of tax (“AOCI”), based on whether the instrument is designated and effective as a hedge transaction. Gains and losses on derivative instruments recorded to AOCI are reclassified to earnings in the period the hedged item affects earnings. The Company’s interest rate swaps are valued based on readily-observable market inputs, such as quotations on interest rates and LIBOR yield curves at the reporting date. The Company’s foreign currency forward contracts are valued based on quoted forward foreign exchange prices and spot rates at the reporting date. The Company’s total return swaps are valued using closing stock prices at the reporting date. Income Taxes The Company recognizes deferred tax assets and liabilities for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Valuation allowances are provided against deferred tax assets when it is considered more likely than not that some portion or all of the deferred tax asset will not be realized within a reasonable time period. The Company assesses tax positions using a two‑step process. A tax position is recognized if it meets a more‑likely‑than‑not threshold and is measured at the largest amount of benefit that has a greater than 50% percent likelihood of being realized. Uncertain tax positions are reviewed each balance sheet date. Foreign Currency Translation and Transactions The functional currency for the international subsidiaries is the local currency. Assets and liabilities are translated into U.S. dollars using current rates of exchange, with the resulting translation adjustments recorded in Accumulated other comprehensive income, net of tax within shareholders’ equity. Revenue and expenses are translated at the weighted‑average exchange rate for the period, with the resulting translation adjustments recorded in the Consolidated Statements of Operations. Foreign currency translation losses (gains), mainly related to intercompany loans, which aggregated $18,712, $(927) and $(8,216) for the years ended September 30, 2022, 2021 and 2020, respectively, are primarily included in General and administrative expenses in the Consolidated Statements of Operations. Research and Development Costs Research and development costs are expensed as incurred. Equity‑based Compensation The Company measures the cost of awards of equity instruments to employees based on the grant‑date fair value of the award. The grant‑date fair value of a non-qualified stock option is determined using the Black‑Scholes model. The grant-date fair value of restricted stock unit awards is determined using the closing price of the Company’s common stock on date of grant. For performance share units, performance metrics are valued using the grant-date fair value and the market conditions are valued using a Monte Carlo simulation. Compensation costs resulting from equity-based payment transactions are recognized primarily within General and administrative expenses, at fair value over the requisite vesting period on a straight-line basis. Earnings (Loss) Per Share Basic earnings (loss) per common share is computed based on the weighted average number of shares of common stock outstanding during the period. Diluted earnings per common share is computed based on the weighted average number of shares of common stock, plus the effect of diluted common shares outstanding during the period using the treasury stock method. Diluted potential common shares include outstanding stock options. Retirement Benefits The Company applies ASC Topic 715, Compensation—Retirement Benefits , which requires the recognition in pension obligations and accumulated other comprehensive income of actuarial gains or losses, prior service costs or credits and transition assets or obligations that have previously been deferred. The determination of retirement benefit pension obligations and associated costs requires the use of actuarial computations to estimate participant plan benefits to which the employees will be entitled. The significant assumptions primarily relate to discount rates, expected long‑term rates of return on plan assets, rate of future compensation increases, mortality, years of service, and other factors. The Company develops each assumption using relevant experience in conjunction with market‑related data for each individual country in which such plans exist. All actuarial assumptions are reviewed annually with third‑party consultants and adjusted as necessary. For the recognition of net periodic postretirement cost, the calculation of the expected return on plan assets is generally derived by applying the expected long‑term rate of return on the market‑related value of plan assets. The fair value of plan assets is determined based on actual market prices or estimated fair value at the measurement date. Recent Accounting Pronouncements

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	Variable Interest Entities Treated Water Outsourcing (“TWO”) was a joint venture between the Company and Nalco Water, an Ecolab company, in which the Company held a 50% partnership interest. The Company acquired the remaining partnership interest in TWO from Nalco Water on April 1, 2022. See Note 4, “Acquisitions and Divestitures” for further discussion. Prior to acquisition, the Company was obligated to absorb all risk of loss up to 100% of the joint venture partner’s equity. As such, the Company fully consolidated TWO as a variable interest entity (“VIE”) under ASC Topic No. 810, Consolidation . The following provides a summary of TWO’s balance sheet as of September 30, 2021 and summarized financial information for the fiscal years ended September 30, 2022, 2021 and 2020. As a result of the acquisition of the remaining partnership interest in TWO on April 1, 2022, there is no summarized balance sheet as of September 30, 2022. September 30, Current assets (includes cash of $1,380) $ 3,202 Property, plant, and equipment 903 Goodwill 2,206 Total liabilities (1,009) Year Ended September 30, 2022 2021 2020 Total revenue $ 1,641 $ 3,315 $ 5,944 Total operating expenses (1,440) (2,922) (4,519) Income from operations $ 201 $ 393 $ 1,425 On October 1, 2019, the Company acquired a 60% investment position in San Diego-based Frontier Water Systems, LLC (“Frontier”). The Frontier acquisition was a VIE because it had insufficient equity to finance its activities due to key assets being assigned to the Company upon acquisition. The Company was the primary beneficiary of Frontier because the Company had the power to direct the activities that most significantly affect Frontier’s economic performance. In addition, the Company entered into an agreement to purchase the remaining 40% interest in Frontier on or prior to March 30, 2024. This agreement (a) gave holders of the remaining 40% interest in Frontier (the “Minority Owners”) the right to sell to Evoqua up to approximately 10% of the outstanding equity in Frontier at a predetermined price, which right was exercisable by the Minority Owners between January 1, 2021 and February 28, 2021 (the “Option”), and (b) obligated the Company to purchase and the Minority Owners to sell all of the Minority Owners’ remaining interest in Frontier at the fair market value at the time of sale on or prior to March 30, 2024 (the “Purchase Right”). The Company acquired an additional 8% equity interest in Frontier in April 2021. O n April 1, 2022, the Company purchased the remaining 32% outstanding equity in Frontier. See Note 4, “Acquisitions and Divestitures” for further discussion. The following provides a summary of Frontier’s balance sheet as of September 30, 2021, and summarized financial information for the fiscal years ended September 30, 2022, 2021 and 2020. As a result of the acquisition of the remaining equity interest in Frontier on April 1, 2022, there is no summarized balance sheet as of September 30, 2022. September 30, Current assets (includes cash of $2,095) $ 12,495 Property, plant, and equipment 2,113 Goodwill 1,798 Intangible assets, net 8,265 Total liabilities (9,425) Year Ended September 30, 2022 2021 2020 Total revenue $ 13,363 $ 14,340 $ 5,365 Total operating expenses (12,135) (14,362) (8,219) Income (loss) from operations $ 1,228 $ (22) $ (2,854)

Acquisitions and Divestitures

Acquisitions and Divestitures	12 Months Ended
	Sep. 30, 2022
Business Combinations [Abstract]
Acquisitions and Divestitures	Acquisitions and Divestitures Acquisitions support the Company’s strategy of delivering a broad solutions portfolio with robust technology across multiple geographies and end markets. The Company continues to evaluate potential strategic acquisitions of businesses, assets and product lines and believes that capex-like, tuck-in acquisitions present a key opportunity within its overall growth strategy. 2022 Acquisitions On July 15, 2022, the Company completed the acquisition of Epicor, Inc. (“Epicor”) for $4,339 cash paid at closing. Epicor has supplied specialty resins for power steam system treatment for fifty years. The resins provide a cost-effective and efficient method for creating and maintaining a continual supply of ultra-pure water for power plants. The acquisition of Epicor did not meet the definition of a business under ASC 805, and as such was accounted for as an asset acquisition. During the year ended September 30, 2022 , the Company incurred approximately $172 in acquisition costs, which due to the inconsequential amount, the Company elected to include in General and administrative expense on the Consolidated Statements of Operations. Epicor is included within the Integrated Solutions and Services segment. The table below summarizes the Company’s allocation of the purchase price to the individual assets acquired based on their relative fair values using the cost accumulation and allocation model. Other current assets $ 40 Property, plant, and equipment, net 116 Intangible assets, net 4,281 Other non-current assets 472 Total assets acquired $ 4,909 Current liabilities (456) Non-current liabilities (114) Total liabilities assumed $ (570) Net assets acquired $ 4,339 On July 1, 2022, the Company completed the acquisition of Smith Engineering, Inc. (“Smith Engineering”) for $18,878 cash paid at closing, of which $2,895 was paid into an escrow account. Smith Engineering is a leader in the design, manufacturing, and service of custom high purity water treatment equipment serving the biotech/pharmaceutical, data center, food and beverage, healthcare, medical device, and microelectronics markets. With over 1,200 customers in North America, Smith Engineering offers a variety of water treatment products and services, including filtration, UV, reverse osmosis, and deionization. During the year ended September 30, 2022, the Company incurred approximately $421 in acquisition costs, which are included in General and administrative expense on the Consolidated Statements of Operations. Smith Engineering is included within the Integrated Solutions and Services segment. The acquisition of Smith Engineering has been accounted for using the acquisition method of accounting which requires the assets acquired and liabilities assumed be recognized at their respective fair values as of the acquisition date. Due to the timing of the business combination and the nature of the net assets acquired, at September 30, 2022, the valuation process to determine fair values is not complete and further adjustments are expected in fiscal year 2023. Smith Engineering business's assets and liabilities were measured at estimated fair values at September 30, 2022 primarily using Level 3 inputs. Estimates of fair value represent the Company’s best estimate of assumptions about future events and uncertainties, including significant judgments related to future cash flows, discount rates, margin and revenue growth assumptions including customer attrition rates and others. Inputs used were generally obtained from historical data supplemented by current and anticipated market conditions and growth rates expected as of the acquisition date. As the Company finalizes the fair value of assets acquired and liabilities assumed, additional purchase price allocation adjustments will be recorded during the measurement period, but no later than one year from the date of the acquisition. The preliminary fair value of assets acquired and liabilities assumed were as follows: Receivables, net $ 2,501 Inventories, net 1,345 Other current assets 937 Property, plant, and equipment, net 532 Goodwill 7,820 Intangible assets, net 9,815 Other non-current assets 796 Total assets acquired $ 23,746 Current liabilities (1,834) Non-current liabilities (3,034) Total liabilities assumed $ (4,868) Net assets acquired $ 18,878 On April 1, 2022, the Company acquired the remaining 32% interest in Frontier from the Minority Owners for a purchase price of $10,396 making Frontier a wholly-owned subsidiary of the Company. This followed the Company’s initial acquisition of a 60% equity interest in Frontier in October 2019 and the Company’s acquisition of an additional 8% equity interest in Frontier in April 2021. The total amount paid for the acquisition of Frontier, including those amounts paid in prior periods, was $22,771. Also on April 1, 2022, the Company acquired the remaining 50% partnership interest in TWO from Nalco for a purchase price of $1,099. On December 20, 2021, the Company and its indirect wholly-owned subsidiaries Evoqua Water Technologies LLC (“EWT LLC”) and Evoqua Water Technologies Ltd. (together with EWT LLC, the “Buyer”) entered into an Asset Purchase Agreement (the “Agreement”) with Cantel Medical LLC, Mar Cor Purification, Inc., and certain of their affiliates (collectively, the “Sellers”), each wholly-owned subsidiaries of Steris plc, pursuant to which the Buyer agreed to acquire certain assets of the Sellers and assume certain liabilities of the Sellers that are owned or used or arise in connection with the global operation of the Sellers’ renal business (the “Mar Cor Business”) for an aggregate purchase price of $196,300 in cash at closing (the “Purchase Price”), subject to customary adjustments, including for working capital (the “Transaction”). On January 3, 2022, the Company completed the Transaction to acquire the Mar Cor Business for $194,976 paid in cash at closing, following adjustments. The Company utilized cash on hand and borrowed an additional $160,000 under the 2021 Revolving Credit Facility (as defined below) to fund the Transaction. The Mar Cor Business is included within the Integrated Solutions and Services segment. The Purchase Price includes a $12,300 earn out, which is being held in escrow and will be paid, pro rata, to the Sellers if the Mar Cor Business meets certain sales performance goals through December 31, 2022 (the “Earn Out”). Any portion of the Earn Out not paid to the Sellers during the first year following closing of the Transaction will be returned to the Buyer. A Monte Carlo simulation was performed to determine the fair value of an Earn Out asset for the amount expected to be received back from escrow based on the forecasted achievement of the sales performance goals associated with the Earn Out as of the acquisition date. See Note 6, Fair Value Measurements, for further discussion. In addition, approximately $12,965 of the Purchase Price was placed into an escrow account, of which $9,815 is to secure general indemnification claims against the Sellers and $3,150 is for net working capital adjustments. During the year ended September 30, 2022, the Company incurred approximately $4,865 in acquisition costs, which are included in General and administrative expense on the Consolidated Statements of Operations. The acquisition of the Mar Cor Business has been accounted for using the acquisition method of accounting which requires the assets acquired and liabilities assumed be recognized at their respective fair values as of the acquisition date. The preliminary purchase price allocation included $57,094 of acquired intangible assets, of which $42,181 was assigned to customer relationships and $14,913 was assigned to trade name, developed technology and know-how. The preliminary fair value of the identifiable intangible assets has been estimated using the income approach through a discounted cash flow analysis. The cash flows are based on estimates used to price the Mar Cor Business acquisition, and the discount rates applied were benchmarked with reference to the implied rate of return to the Company’s pricing model and the weighted-average cost of capital. Additionally, the significant assumptions used to determine the fair value of the customer relationships intangible assets were revenue growth and EBITDA margin. These significant assumptions are forward-looking and could be affected by future economic and market conditions. The customer relationship intangible assets are subject to useful lives ranging from 3 to 9 years, and trade name, developed technology and know-how intangible assets are subject to useful lives of 15, 4 and 9 years, respectively. The table below summarizes the preliminary estimated fair values of the assets acquired and liabilities assumed as of the acquisition date. These preliminary estimates are subject to revision during the measurement period as additional analyses are performed and third-party valuations are finalized, and these differences could have a material impact on the accounting for the business combination. Receivables, net $ 21,275 Inventories, net 32,350 Earn Out asset 7,824 Other current assets 1,844 Property, plant, and equipment, net 19,150 Goodwill 68,754 Intangible assets, net 57,094 Other non-current assets 7,694 Total assets acquired $ 215,985 Current liabilities (15,467) Non-current liabilities (5,542) Total liabilities assumed $ (21,009) Net assets acquired $ 194,976 2022 Divestitures On January 31, 2022, the Company completed the divestiture of the resin regeneration assets in Germany (the “Germany Regen Business”) for $356 in cash at closing, resulting in a gain of $193 recognized on the sale, which is included in Other operating income on the Consolidated Statements of Operations. The Germany Regen Business was a part of the Applied Product Technologies segment. 2021 Acquisitions On April 1, 2021, the Company acquired the assets of Water Consulting Specialists, Inc. (“WCSI”) for $12,025 cash paid at closing. In addition, the Company recorded a liability of $761 at closing associated with an earn-out related to the WCSI acquisition, which was subsequently revalued to $150 and is included in Accrued expenses and other liabilities on the Consolidated Balance Sheets. During the year ended September 30, 2021, the Company received cash of $21 from the seller as a result of net working capital adjustments. WCSI is a leader in the design, manufacturing, and service of industrial high-purity water treatment systems. The acquisition strengthens the Company’s portfolio of high-purity water treatment systems and provides the opportunity to further expand its digitally enabled solutions and services in key industrial markets. WCSI is a part of the Integrated Solutions and Services segment. During the year ended September 30, 2021, the Company incurred approximately $83 in acquisition costs, which are included in General and administrative expense on the Consolidated Statements of Operations. The opening balance sheet for WCSI is summarized as follows: Current assets $ 1,813 Property, plant, and equipment 221 Goodwill 4,340 Intangible assets, net 7,336 Other non-current assets 86 Total assets acquired $ 13,796 Liabilities assumed $ (1,792) Net assets acquired $ 12,004 On December 17, 2020, the Company acquired the industrial water business of Ultrapure & Industrial Services, LLC (“Ultrapure”) for $8,743 cash paid at closing. On April 1, 2021, the Company paid an additional $290 as a result of net working capital adjustments. Ultrapure, based out of Texas, provides customers across multiple end markets with a variety of water treatment products and services, including service deionization, reverse osmosis, UV, and ozonation. Ultrapure will strengthen the Company’s service capabilities in the Houston and Dallas markets and is a part of the Integrated Solutions and Services segment. During the year ended September 30, 2021, the Company incurred approximately $230 in acquisition costs, which are included in General and administrative expense on the Consolidated Statements of Operations. The opening balance sheet for Ultrapure is summarized as follows: Current assets $ 2,366 Property, plant, and equipment 963 Goodwill 2,836 Intangible assets, net 3,751 Other non-current assets 21 Total assets acquired $ 9,937 Liabilities assumed $ (904) Net assets acquired $ 9,033 2021 Divestitures On March 1, 2021, the Company completed the divestiture of the Lange containment system, geomembrane and geosynthetic liner product line (the “Lange Product Line”) for $897 in cash at closing. The Lange Product Line was a part of the Integrated Solutions and Services segment. During the year ended September 30, 2021, the Company recognized a loss of $193 on the divestiture, which is included in Other operating expense on the Consolidated Statements of Operations.

Revenue

Revenue	12 Months Ended
	Sep. 30, 2022
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Disaggregation of Revenue In accordance with Topic 606, the Company disaggregates revenue from contracts with customers into source of revenue, reportable operating segment, and geographical regions. The Company determined that disaggregating revenue into these categories meets the disclosure objective in Topic 606 which is to depict how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors. Information regarding the source of revenue: Year Ended September 30, 2022 2021 2020 Revenue from contracts with customers recognized under Topic 606 $ 1,555,565 $ 1,274,096 $ 1,279,772 Other (1) 181,511 190,333 149,684 Total $ 1,737,076 $ 1,464,429 $ 1,429,456 (1) Other revenue relates to revenue recognized pursuant to ASU 2016-02, Leases (Topic 842) , primarily attributable to long term rentals. Information regarding revenue disaggregated by segment and source of revenue is as follows: Year Ended September 30, 2022 2021 2020 Integrated Solutions and Services Revenue from capital projects $ 304,925 $ 250,187 $ 257,528 Revenue from aftermarket 215,972 128,585 119,051 Revenue from service 663,580 581,114 567,603 Total $ 1,184,477 $ 959,886 $ 944,182 Applied Product Technologies Revenue from capital projects $ 383,473 $ 365,791 $ 335,227 Revenue from aftermarket 148,118 116,463 128,051 Revenue from service 21,008 22,289 21,996 Total $ 552,599 $ 504,543 $ 485,274 Total Revenue Revenue from capital projects $ 688,398 $ 615,978 $ 592,755 Revenue from aftermarket 364,090 245,048 247,102 Revenue from service 684,588 603,403 589,599 Total $ 1,737,076 $ 1,464,429 $ 1,429,456 Information regarding revenue disaggregated by geographic area is as follows: Year Ended September 30, 2022 2021 2020 United States $ 1,431,095 $ 1,174,474 $ 1,164,634 Asia 129,981 113,316 77,253 Europe 108,271 113,559 108,139 Canada 54,935 49,952 65,223 Australia 12,794 13,128 14,207 Total $ 1,737,076 $ 1,464,429 $ 1,429,456 Performance Obligations The Company elects to apply the practical expedient to exclude from this disclosure revenue related to performance obligations if the product has an alternative use and the Company does not have an enforceable right to payment for the performance completed to date, including a normal profit margin, in the event of termination for convenience. The Company maintains a backlog of confirmed orders of approximately $377,091 at September 30, 2022. This backlog represents the aggregate amount of the transaction price allocated to performance obligations that were unsatisfied or partially unsatisfied as of the end of the reporting period. The Company estimates that the majority of these performance obligations will be satisfied within the next twelve Contract Balances The tables below provide a roll-forward of contract assets and contract liabilities balances for the periods presented: Year Ended September 30, Contract assets (a) 2022 2021 Balance at beginning of period $ 72,746 $ 80,759 Recognized in current period 401,825 316,864 Reclassified to accounts receivable (368,936) (325,405) Foreign currency (3,512) 528 Balance at end of period $ 102,123 $ 72,746 (a) Excludes receivable balances which are disclosed on the Consolidated Balance Sheets. Year Ended September 30, Contract Liabilities 2022 2021 Balance at beginning of period $ 55,883 $ 26,259 Recognized in current period 370,375 349,046 Amounts in beginning balance reclassified to revenue (44,313) (25,523) Current period amounts reclassified to revenue (319,513) (294,033) Foreign currency 7 134 Balance at end of period $ 62,439 $ 55,883

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value MeasurementsAs of September 30, 2022 and 2021, the fair values of cash and cash equivalents, accounts receivable and accounts payable approximated carrying values due to the short maturity of these items. The Company measures the fair value of pension plan assets and liabilities, deferred compensation and plan assets and liabilities on a recurring basis pursuant to ASC Topic 820. ASC Topic 820 establishes a three‑tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include: Level 1: Quoted prices for identical instruments in active markets. Level 2: Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model‑derived valuations whose inputs are observable or whose significant value driver is observable. Level 3: Unobservable inputs in which little or no market data is available, therefore requiring an entity to develop its own assumptions. The following table presents the Company’s financial assets and liabilities at fair value. The fair values related to the pension assets are determined using net asset value (“NAV”) as a practical expedient, or by information categorized in the fair value hierarchy level based on the inputs used to determine fair value. The reported carrying amounts of deferred compensation assets and liabilities and debt approximate their fair values. The Company uses interest rates and other relevant information generated by market transactions involving similar instruments to measure the fair value of these assets and liabilities, therefore, all are classified as Level 2 within the valuation hierarchy. Net Asset Value Quoted Market Significant Other Significant As of September 30, 2022 Assets: Pension plan Cash $ — $ 40 $ — $ — Global Multi-Asset Fund 11,632 — — — Government Securities 3,343 — — — Liability Driven Investment 928 — — — Guernsey Unit Trust 2,048 — — — Global Absolute Return 1,299 — — — Deferred compensation plan assets Cash — 902 — — Mutual Funds — 12,330 — — Earn-out assets related to acquisitions — — — 11,597 Interest rate swaps — — 49,952 — Foreign currency forward contracts — — 507 — Liabilities: Pension plan — — (26,654) — Deferred compensation plan liabilities — — (20,081) — Total return swaps—deferred compensation — — (632) — Long‑term debt — — (884,517) — Foreign currency forward contracts — — (872) — Commodity swaps — — (7) — As of September 30, 2021 Assets: Pension plan Cash $ — $ 831 $ — $ — Global Multi-Asset Fund 15,244 — — — Government Securities 5,158 — — — Liability Driven Investment 2,793 — — — Guernsey Unit Trust 2,387 — — — Global Absolute Return 2,225 — — — Deferred compensation plan assets Cash — 1,251 — — Mutual Funds — 17,806 — — Interest rate swaps — — 3,127 — Foreign currency forward contracts — — 24 — Liabilities: Pension plan — — (46,013) — Deferred compensation plan liabilities — — (24,382) — Total return swaps—deferred compensation — — (130) — Long‑term debt — — (752,988) — Interest rate swaps — — (303) — Foreign currency forward contracts — — (102) — Commodity swaps — — (19) — Earn-out liabilities related to acquisitions — — — (150) Purchase Right — — — (8,305) The pension plan assets and liabilities and deferred compensation assets and liabilities are included in other non-current assets and other non-current liabilities on the Consolidated Balance Sheets at September 30, 2022 and 2021. The unrealized loss on mutual funds was $2,537 at September 30, 2022. The Company records contingent consideration arrangements at fair value on a recurring basis and the associated balances presented as of September 30, 2022 and 2021 are earn-outs related to acquisitions. See Note 4, “Acquisitions and Divestitures” for further discussion regarding the earn-outs recorded for specific acquisitions. The fair value of earn-outs related to acquisitions is based on significant unobservable inputs including the achievement of certain performance metrics. Significant changes in these inputs would result in corresponding increases or decreases in the fair value of the earn-out each period until the related contingency has been resolved. Changes in the fair value of the contingent consideration obligations and assets can result from adjustments in the probability of achieving future development steps, sales targets and profitability and are recorded in General and administrative expenses in the Consolidated Statements of Operations. During the year ended September 30, 2022, the Company recorded a decrease in the fair value of the earn-out liability related to the prior year acquisition of Water Consulting Specialists, Inc. (“WCSI”) of $150. A rollforward of the activity in the Company’s fair value of earn-out liabilities related to acquisitions is as follows: Current Portion (1) Long-term Portion (2) Total Balance at September 30, 2020 $ 295 $ — $ 295 Acquisitions 761 — 761 Payments (170) — (170) Fair value adjustment (736) — (736) Balance at September 30, 2021 $ 150 $ — $ 150 Fair value adjustment (150) — (150) Balance at September 30, 2022 $ — $ — $ — (1) Included in Accrued expenses and other liabilities on the Consolidated Balance Sheets. (2) Included in Other non‑current liabilities on the Consolidated Balance Sheets. As a result of the Mar Cor Business acquisition on January 3, 2022, the Company recorded an Earn Out asset for $7,824 which represented the fair value of amounts expected to be received back from escrow based on the forecasted achievement of certain sales performance goals at the acquisition date. During the year ended September 30, 2022, the Company recorded an increase in the fair value of the Earn Out asset of $3,773 based on updated forecast information. As of September 30, 2022 and September 30, 2021, earn-out assets related to acquisitions total $11,597 and $0, respectively, and are included in Prepaid and other current assets on the Consolidated Balance Sheets.

Accounts Receivable

Accounts Receivable	12 Months Ended
	Sep. 30, 2022
Receivables [Abstract]
Accounts receivable	Accounts Receivable Accounts receivable are summarized as follows: September 30, 2022 September 30, 2021 Accounts Receivable $ 312,600 $ 282,819 Allowance for Credit Losses (6,888) (4,824) Receivables, net $ 305,712 $ 277,995 The movement in the allowance for credit losses was as follows: Year Ended September 30, 2022 2021 2020 Balance at beginning of period $ (4,824) $ (4,057) $ (4,906) Charged to costs and expenses (1,997) (1,733) (537) Write-offs 473 780 1,277 Foreign currency and other (540) 186 109 Balance at end of period $ (6,888) $ (4,824) $ (4,057)

Inventories

Inventories	12 Months Ended
	Sep. 30, 2022
Inventory Disclosure [Abstract]
Inventories	Inventories The major classes of inventory, net are as follows: September 30, 2022 September 30, 2021 Raw materials and supplies $ 120,532 $ 86,469 Work in progress 36,499 19,842 Finished goods and products held for resale 80,811 59,624 Costs of unbilled projects 2,309 2,277 Reserves for excess and obsolete (10,800) (9,709) Inventories, net $ 229,351 $ 158,503 The following is the activity in the reserves for excess and obsolete inventory: Year Ended September 30, 2022 2021 2020 Balance at beginning of period $ (9,709) $ (11,467) $ (13,370) Change to reserve requirement (2,608) 265 (310) Write-offs 684 1,516 2,197 Foreign currency and other 833 (23) 16 Balance at end of period $ (10,800) $ (9,709) $ (11,467)

Property, Plant, and Equipment

Property, Plant, and Equipment	12 Months Ended
	Sep. 30, 2022
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant, and Equipment Property, plant, and equipment consists of the following: September 30, 2022 September 30, 2021 Machinery and equipment $ 401,334 $ 388,352 Rental equipment 267,345 246,257 Land and buildings 82,985 70,048 Construction in process 72,184 59,737 $ 823,848 $ 764,394 Less: accumulated depreciation (418,559) (389,406) Property, plant, and equipment, net $ 405,289 $ 374,988 The Company entered into secured financing agreements that require providing a security interest in specified equipment. As of September 30, 2022 and September 30, 2021, the gross and net amounts of those assets are as follows: September 30, 2022 September 30, 2021 Gross Net Gross Net Machinery and equipment $ 86,294 $ 62,459 $ 73,632 $ 57,036 Construction in process 49,983 49,983 30,504 30,504 $ 136,277 $ 112,442 $ 104,136 $ 87,540 Depreciation expense and maintenance and repairs expense for the years ended September 30, 2022, 2021 and 2020 were as follows: Year Ended September 30, 2022 2021 2020 Depreciation expense $ 82,637 $ 76,279 $ 73,002 Maintenance and repair expense $ 30,425 $ 22,354 $ 20,303

Goodwill

Goodwill	12 Months Ended
	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill Changes in the carrying amount of goodwill are as follows: Integrated Solutions and Services Applied Product Technologies Total Balance at September 30, 2020 $ 224,381 $ 172,824 $ 397,205 Business combinations and divestitures 10,349 — 10,349 Measurement period adjustments (3,216) — (3,216) Foreign currency translation 2,316 722 3,038 Balance at September 30, 2021 $ 233,830 $ 173,546 $ 407,376 Business combinations and divestitures 76,190 (34) $ 76,156 Measurement period adjustments 379 — 379 Foreign currency translation (3,464) (6,875) (10,339) Balance at September 30, 2022 $ 306,935 $ 166,637 $ 473,572 As of September 30, 2022 and 2021, $250,636 and $159,730, respectively, of goodwill is deductible for tax purposes.

Other Intangible Assets

Other Intangible Assets	12 Months Ended
	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Other Intangible Assets	Other Intangible Assets Intangible assets consist of the following: September 30, 2022 Estimated Life (years) Carrying Amount Accumulated Amortization Net Amortizing intangible assets Customer related 3 - 26 $ 346,128 $ (122,604) $ 223,524 Proprietary technology 4 - 10 68,586 (44,532) 24,054 Trademark 3 - 15 32,711 (15,056) 17,655 Backlog 1 81,159 (81,159) — Other 3 - 10 57,719 (39,426) 18,293 Total amortizing intangible assets $ 586,303 $ (302,777) $ 283,526 Indefinite‑lived intangible assets 34,207 — 34,207 Total intangible assets $ 620,510 $ (302,777) $ 317,733 September 30, 2021 Estimated Life (years) Carrying Amount Accumulated Amortization Net Amortizing intangible assets Customer related 5 - 26 $ 300,963 $ (101,272) $ 199,691 Proprietary technology 7 - 10 61,692 (36,921) 24,771 Trademark 5 - 15 27,195 (12,191) 15,004 Backlog 1 82,355 (82,355) — Other 3 - 10 47,903 (31,501) 16,402 Total amortizing intangible assets $ 520,108 $ (264,240) $ 255,868 Indefinite‑lived intangible assets 34,207 — 34,207 Total intangible assets $ 554,315 $ (264,240) $ 290,075 The Company’s indefinite-lived intangible asset relate to Federal hazardous waste treatment management permits obtained for locations operated by the Integrated Solutions and Services segment. The permits are considered perpetually renewable. The Company performs an indefinite-lived intangible asset impairment analysis on an annual basis during the fourth quarter of the year and whenever events or changes in circumstances indicate that the carrying value may not be recoverable. The Company assessed the carrying value of the permits at the Integrated Solutions and Services segment as of July 1, 2022, the annual measurement date, using a quantitative analysis outlined in ASU No. 2012-02 to determine whether the existence of events or circumstances would lead to the conclusion that it is more likely than not that the fair values of the permits are less than the carrying amounts. Events and circumstances considered in this review included macroeconomic conditions, new competition, financial performance of the entities which utilizes the permits and other financial and non-financial events. Based on these factors, the Company concluded the fair value of the permits were not more likely than not less than the carrying amounts. For the amortizing intangible assets, the remaining weighted-average amortization period at September 30, 2022 was as follows: Years Customer-related intangibles 8 Proprietary technology 3 Trademarks 6 Other 3 Aggregate net intangible assets 6 Intangible asset amortization was $44,934, $37,385, and $34,266 for the years ended September 30, 2022, 2021 and 2020, respectively. The estimated future amortization expense is as follows: 2023 $ 44,421 2024 38,994 2025 33,960 2026 28,596 2027 24,070 Thereafter 113,485 Total $ 283,526

Debt

Debt	12 Months Ended
	Sep. 30, 2022
Debt Disclosure [Abstract]
Debt	Debt Long‑term debt consists of the following: September 30, September 30, 2021 Term Loan, due April 1, 2028 $ 469,063 $ 473,837 2021 Revolving Credit Facility, due April 1, 2026 151,254 37,268 Securitization Facility, due April 1, 2024 150,201 150,061 Equipment Financing, due September 30, 2023 to September 30, 2032, interest rates ranging from 3.59% to 8.07% 120,155 93,375 Notes Payable, due July 31, 2023 (1) — 402 Total debt $ 890,673 $ 754,943 Less unamortized deferred financing fees (9,873) (11,738) Total net debt $ 880,800 $ 743,205 Less current portion (17,266) (12,775) Total long‑term debt $ 863,534 $ 730,430 (1) In March 2022, the outstanding balance of the Notes Payable due July 31, 2023, was repaid in conjunction with the Company’s acquisition of TWO. See Note 4, “Acquisitions and Divestitures” for further discussion. 2021 Credit Agreement On April 1, 2021, EWT III entered into a Credit Agreement (the “2021 Credit Agreement”) among EWT III, as borrower, EWT II, as parent guarantor, the lenders from time to time party thereto, JPMorgan Chase Bank, N.A., as administrative agent and collateral agent, and ING Capital, LLC, as sustainability coordinator. The 2021 Credit The 2021 Credit Agreement contains customary representations, warranties, affirmative covenants, and negative covenants, including, among other things, a springing maximum first lien leverage ratio of 5.55 to 1.00. The Company did not exceed this ratio during the year ended September 30, 2022, does not anticipate exceeding this ratio during the fiscal year ending September 30, 2023, and therefore does not anticipate any additional repayments during the year ending September 30, 2023. With respect to the 2021 Revolving Credit Facility, EWT III is required to pay a commitment fee based on the daily unused portion of the 2021 Revolving Credit Facility, as well as certain other fees to the agents and the arrangers under the Senior Facilities. Amounts outstanding under the Senior Facilities, at EWT III’s option, bear interest at either (i) a Base Rate determined in accordance with the terms of the 2021 Credit Agreement, (ii) with respect to any amounts denominated in U.S. dollars or Sterling, LIBOR, or replacement thereof, as determined in accordance with the terms of the 2021 Credit Agreement, or (iii) with respect to amounts denominated in Euros, the EURIBOR, or replacement thereof, as determined in accordance with the terms of the 2021 Credit Agreement. In the case of the 2021 Revolving Credit Facility, an applicable margin based on the consolidated total leverage of EWT III and its restricted subsidiaries, as calculated in accordance with the terms of the 2021 Credit Agreement, will be added to the interest rate elected by EWT III. During fiscal 2022, the spread on the 2021 Revolving Credit Facility was reduced to 2.20% from 2.25% as a result of a Sustainability Pricing Adjustment per the 2021 Credit Agreement. In the case of the 2021 Term Loan, a fixed applicable margin, calculated in accordance with the terms of the 2021 Credit Agreement, will be added to the interest rate elected by EWT III. On April 1, 2021, EWT III borrowed the full amount of $475,000 under the 2021 Term Loan and $105,000 under the 2021 Revolving Credit Facility. The 2021 Term Loan was issued at a discount of $2,375, which is recorded as a contra-liability to the carrying amount of debt issued, and is being amortized to interest expense using the effective interest method. The net proceeds of these borrowings under the Senior Facilities, together with the net proceeds of the Receivables Securitization Program (as defined below) and cash on hand, were used to repay all outstanding indebtedness, in an aggregate principal amount of approximately $814,538, under the 2014 Credit Agreement. The proceeds of the 2021 Revolving Credit Facility may also be used to finance or refinance the working capital and capital expenditures needs of EWT III and certain of its subsidiaries and for general corporate purposes. The 2021 Term Loan matures on April 1, 2028 and requires quarterly principal payments of $1,188 that started in the fourth quarter of 2021. Subject to the terms of the 2021 Credit Agreement, to the extent not previously paid, any amount owed under the 2021 Revolving Credit Facility will become due and payable in full on April 1, 2026. At September 30, 2022, the Company had (a) $469,063 outstanding under the 2021 Term Loan at an interest rate of 5.06%, comprised of 2.56% LIBOR plus the 2.50% spread, and (b) $151,254 outstanding under the 2021 Revolving Credit Facility with an interest rate of 5.33%, comprised of 3.13% LIBOR plus a 2.20% spread. The 2021 Revolving Credit Facility includes $254 of accrued interest at September 30, 2022. At September 30, 2021 the Company had (a) $473,837 outstanding under the 2021 Term Loan at an interest rate of 2.63%, comprised of 0.13% LIBOR plus the 2.50% spread, and (b) 37,268 outstanding under the 2021 Revolving Credit Facility with an interest rate of 2.38%, comprised of 0.13% LIBOR plus a 2.25% spread. The 2021 Revolving Credit Facility includes $268 of accrued interest at September 30, 2021. The following table summarizes the amount of the Company’s outstanding borrowings and outstanding letters of credit under the 2021 Revolving Credit Facility as of September 30, 2022, and September 30, 2021. September 30, September 30, Borrowing availability $ 350,000 $ 350,000 Outstanding borrowings 151,000 37,000 Outstanding letters of credit 9,317 10,112 Unused amounts $ 189,683 $ 302,888 Receivables Securitization Program On April 1, 2021, Evoqua Finance LLC (“Evoqua Finance”), an indirect wholly-owned subsidiary of the Company, entered into an accounts receivable securitization program (the “Receivables Securitization Program”) consisting of, among other agreements, (i) a Receivables Financing Agreement (the “Receivables Financing Agreement”) among Evoqua Finance, as the borrower, the lenders from time to time party thereto (the “Receivables Financing Lenders”), PNC Bank, National Association (“PNC Bank”), as administrative agent, Evoqua Water Technologies LLC (“EWT LLC”), an indirect wholly-owned subsidiary of the Company, as initial servicer, and PNC Capital Markets LLC (“PNC Markets”), as structuring agent, pursuant to which the lenders have made available to Evoqua Finance a receivables finance facility (the “Securitization Facility”) in an amount up to $150,000 and (ii) a Sale and Contribution Agreement (the “Sale Agreement”) among Evoqua Finance, as purchaser, EWT LLC, as initial servicer and as an originator, and Neptune Benson, Inc., an indirectly wholly-owned subsidiary of the Company, as an originator (together with EWT LLC, the “Originators”). Under the Receivables Securitization Program, the Originators, pursuant to the Sale Agreement, are required to sell substantially all of their domestic trade receivables and certain related rights to payment and obligations of the Originators with respect to such receivables (the “Receivables”) to Evoqua Finance, which, in turn, will obtain loans secured by the Receivables from the Receivables Financing Lenders pursuant to the Receivables Financing Agreement. The Receivables underlying any borrowings will continue to be included in Accounts receivable, net, in the Consolidated Balance Sheets of the Company. On April 1, 2021, Evoqua Finance borrowed $142,200 under the Securitization Facility. During the year ended September 30, 2022, Evoqua Finance borrowed additional amounts under the Securitization Facility. As of September 30, 2022 Evoqua Finance had $150,201 outstanding under the Securitization Facility which included $201 of accrued interest. As of September 30, 2021 Evoqua Finance had $150,061 outstanding under the Securitization Facility which included $61 of accrued interest. The Receivables Securitization Program contains certain customary representations, warranties, affirmative covenants, and negative covenants, subject to certain cure periods in some cases, including the eligibility of the Receivables being sold by the Originators and securing the loans made by the Receivables Financing Lenders, as well as customary reserve requirements, events of default, termination events, and servicer defaults. The Company was in compliance with all covenants during the fiscal year ended September 30, 2022, does not anticipate becoming noncompliant during the year ending September 30, 2023, and therefore does not anticipate any additional repayments during the year ending September 30, 2023. The Receivables Financing Lenders under the Receivables Securitization Program receive interest at LIBOR or LMIR as selected by Evoqua Finance. The Receivables Financing Agreement contains customary LIBOR benchmark replacement language. The interest rate on the Securitization Facility was 4.39% as of September 30, 2022, comprised of 3.14% LIBOR plus the 1.25% spread. As of September 30, 2021 the interest rate on the Securitization Facility was 1.33%, comprised of 0.08% LIBOR plus the 1.25% spread The Receivables Securitization Program matures on April 1, 2024. Equipment Financings During the year ended September 30, 2022, the Company completed the following equipment financings: Date Entered Due Interest Rate at September 30, 2022 Principal Amount September 30, 2022 September 30, 2032 5.30 % $ 3,811 September 29, 2022 May 31, 2029 (1) 5.03 % 2,248 June 30, 2022 July 31, 2029 (2) 6.31 % 12,356 June 30, 2022 May 31, 2029 (1) 5.03 % 4,086 March 18, 2022 March 17, 2029 4.67 % 1,839 March 16, 2022 July 31, 2029 (2) 6.31 % 1,317 March 15, 2022 April 1, 2029 4.67 % 4,788 December 30, 2021 December 30, 2028 3.94 % 2,207 December 23, 2021 July 31, 2029 (2) 6.31 % 3,742 $ 36,394 (1) Represents an advance received from the lender on a multiple draw term loan in which the Company is making interest only payments through December 30, 2022 based on a 2.28% Secured Overnight Financing Rate plus a 2.75% spread. (2) Represents an advance received from the lender on a multiple draw term loan in which the Company is making interest only payments through August 1, 2022 based on an interest rate of 6.31% including a 2.56% LIBOR plus a 3.75% spread as of September 30, 2022. The Company entered into an interest rate swap with an effective date of August 1, 2022 to mitigate risk associated with this variable rate equipment financing, see Note 13, “Derivative Financial Instruments” for further discussion. Deferred Financing Fees and Discounts Deferred financing fees and discounts related to the Company’s long-term debt were included as a contra liability to debt on the Consolidated Balance Sheets as follows: September 30, September 30, Current portion of deferred financing fees and discounts (1) $ (1,899) $ (1,866) Long-term portion of deferred financing fees and discounts (2) (7,974) (9,872) Total deferred financing fees and discounts $ (9,873) $ (11,738) (1) Included in Current portion of debt, net of deferred financing fees and discounts on the Consolidated Balance Sheets. (2) Included in Long-term debt, net of deferred financing fees and discounts on the Consolidated Balance Sheets. During the year ended September 30, 2021, as a result of the refinancing on April 1, 2021, the Company wrote off approximately $1,333 of deferred financing fees related to the 2014 Term Loan. In addition, the Company incurred approximately $4,985 of fees, of which approximately $1,931 were recorded as deferred financing fees on the Consolidated Balance Sheets and approximately $3,054 were expensed. During the year ended September 30, 2021, the Company incurred approximately $822 of fees related to the Receivables Securitization Program and $453 of fees related to an equipment financing which were recorded as deferred financing fees on the Consolidated Balance Sheets. Amortization of deferred financing fees and discounts included in interest expense were $1,866, $1,946, and $1,735 for the year ended September 30, 2022, 2021 and 2020, respectively. Repayment Schedule Aggregate maturities of all long‑term debt, including current portion of long‑term debt and excluding finance lease obligations as of September 30, 2022, are presented below: Fiscal Year 2023 $ 19,085 2024 167,870 2025 19,458 2026 173,775 2027 21,031 Thereafter 489,454 Total $ 890,673

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Sep. 30, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities Disclosure [Text Block]	Derivative Financial Instruments Interest Rate Risk Management The Company is subject to market risk exposure arising from changes in interest rates on the senior secured credit facilities as well as variable rate equipment financings, which bear interest at rates that are indexed against LIBOR. The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to mitigate its exposure to rising interest rates. As of September 30, 2022, the notional amount of the Company’s interest rate swaps was $540,000. Foreign Currency Risk Management The Company’s functional currency is the U.S. dollar. By operating internationally, the Company is subject to foreign currency translation risk associated with converting the foreign operations’ financial statements into U.S. dollars transactions denominated in currencies other than the U.S. dollar (“foreign currencies”). The Company is also subject to currency risk from transactions denominated in foreign currencies. To mitigate cross-currency transaction risk, the Company analyzes significant exposures where it has receipts or payments in a currency other than the functional currency of its operations, and from time to time may strategically enter into short-term foreign currency forward contracts to lock in some or all of the cash flows associated with these transactions. The Company uses foreign currency derivative contracts in order to manage the effect of exchange fluctuations on forecasted sales and purchases that are denominated in foreign currencies. To mitigate the impact of foreign exchange rate fluctuation risk, the Company entered into a series of forward contracts designated as cash flow hedges. As of September 30, 2022, the notional amount of the forward contracts was $26,106. Equity Price Risk Management The Company is exposed to variability in compensation charges related to certain deferred compensation obligations to employees. Equity price movements affect the compensation expense as certain investments made by the Company’s employees in the deferred compensation plan are revalued. Although not designated as accounting hedges, the Company utilizes derivatives such as total return swaps to economically hedge a portion of this exposure and offset the related compensation expense. As of September 30, 2022, the notional amount of the total return swaps was $5,629. Credit Risk Management The counterparties to the Company’s derivative contracts are highly rated financial institutions. The Company regularly reviews the creditworthiness of its financial counterparties and does not expect to incur a significant failure of any counterparties to perform under any agreements. The Company is not subject to any obligations to post collateral under derivative instrument contracts. The Company records all derivative instruments on a gross basis in the Consolidated Balance Sheets. Accordingly, there are no offsetting amounts that net assets against liabilities. Derivatives Designated as Cash Flow Hedges The following represents the fair value recorded for derivatives designated as cash flow hedges for the periods presented: Asset Derivatives Balance Sheet Location September 30, 2022 September 30, 2021 Interest rate swaps Prepaid and other current assets $ 19,186 $ 3,127 Foreign currency forward contracts Prepaid and other current assets 467 6 Interest rate swaps Other non‑current assets 30,766 — Liability Derivatives Balance Sheet Location September 30, 2022 September 30, 2021 Foreign currency forward contracts Accrued expenses and other current liabilities $ 872 $ 102 Commodity swaps Accrued expenses and other current liabilities 7 19 Interest rate swaps Accrued expenses and other current liabilities — 303 The following represents the amount of gain (loss) recognized in AOCI (net of tax) during the periods presented: Year Ended September 30, 2022 2021 2020 Interest rate swap $ 36,550 $ 5,252 $ (5,155) Foreign currency forward contracts (583) (324) (201) Commodity swaps 8 (19) — Interest rate cap — — (19) $ 35,975 $ 4,909 $ (5,375) The following represents the amount of (loss) gain reclassified from AOCI into earnings during the periods presented: Year Ended September 30, Location of (Loss) Gain 2022 2021 2020 Cost of product sales and services $ (136) $ (70) $ (8) General and administrative expense (229) (4) (192) Selling and marketing expense — (69) 28 Interest expense 1,152 (2,241) (486) $ 787 $ (2,384) $ (658) Based on the fair value amounts of the Company’s cash flow hedges at September 30, 2022, the Company expects that approximately $186 of pre-tax net losses will be reclassified from AOCI into earnings during the next twelve months. The amount ultimately realized, however, will differ as exchange rates vary and the underlying contracts settle. Derivatives Not Designated as Hedging Instruments The following represents the fair value recorded for derivatives not designated as hedges for the periods presented: Asset Derivatives Balance Sheet Location September 30, September 30, Foreign currency forward contracts Prepaid and other current assets $ 40 $ 18 Liability Derivatives Balance Sheet Location September 30, September 30, Total return swaps—deferred compensation Accrued expenses and other current liabilities $ 632 $ 130 The following represents the amount of loss recognized in earnings for derivatives not designated as hedges during the periods presented: Year Ended September 30, Location of Loss 2022 2021 2020 General and administrative expense $ (1,130) $ (106) $ — $ (1,130) $ (106) $ —

Product Warranties

Product Warranties	12 Months Ended
	Sep. 30, 2022
Guarantees and Product Warranties [Abstract]
Product warranties	Product Warranties A reconciliation of the activity related to the accrued warranty, including both the current and long‑term portions, is as follows: Current Product Warranties Non-Current Product Warranties Year Ended September 30, Year Ended September 30, 2022 2021 2020 2022 2021 2020 Balance at beginning of the period $ 8,138 $ 6,115 $ 4,922 $ 2,966 $ 1,724 $ 2,332 Warranty provision for sales 6,732 6,939 4,738 2,835 2,065 701 Settlement of warranty claims (7,206) (4,720) (4,890) (2,022) (830) (1,170) Foreign currency translation and other (924) (196) 550 (314) 7 (274) Amounts related to sale of the Memcor product line — — 795 — — 135 Balance at end of the period $ 6,740 $ 8,138 $ 6,115 $ 3,465 $ 2,966 $ 1,724

Restructuring and Related Charg

Restructuring and Related Charges	12 Months Ended
	Sep. 30, 2022
Restructuring and Related Activities [Abstract]
Restructuring and related charges	Restructuring and Related Charges To better align its resources with its growth strategies and reduce the cost structure, the Company commits to restructuring plans as necessary. The Company has undertaken various restructuring initiatives, including undertaking activities to reduce the cost structure and rationalize location footprint following the sale of the Memcor product line, transitioning from a three-segment structure to a two-segment operating model designed to better serve the needs of customers worldwide, and various initiatives within the Integrated Solutions and Services segment to drive efficiency and effectiveness in certain divisions. The Company currently expects to incur approximately $8,400 to $9,400 of costs during fiscal 2023 related to restructuring charges initiated in prior periods. The table below sets forth the amounts accrued for the restructuring components and related activity: Year Ended September 30, 2022 2021 2020 Balance at beginning of the period $ 304 $ 970 $ 655 Restructuring charges following the sale of the Memcor product line 979 5,588 8,274 Restructuring charges related to two-segment realignment 390 1,060 2,092 Restructuring charges related to other initiatives 4,517 2,830 1,867 Release of prior reserves (300) (329) (98) Write-off charges — (1,340) (2,461) Cash payments (5,222) (8,484) (9,367) Other adjustments (10) 9 8 Balance at end of the period $ 658 $ 304 $ 970 The balances for accrued restructuring liabilities at September 30, 2022 and 2021, are recorded in Accrued expenses and other liabilities on the Consolidated Balance Sheets. Restructuring charges primarily represent severance charges and other employee costs, fixed asset write-offs and certain relocation expenses. The Company expects to pay the remaining amounts accrued as of September 30, 2022 during the first half of 2023. The table below sets forth the location of amounts recorded above on the Consolidated Statements of Operations: Year Ended September 30, 2022 2021 2020 Cost of product sales and services $ 2,217 $ 4,554 $ 8,305 General and administrative expense 2,574 3,199 3,053 Sales and marketing expense 83 348 305 Research and development expense 1 (16) 23 Other operating expense, net 711 1,064 449 $ 5,586 $ 9,149 $ 12,135

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Sep. 30, 2022
Retirement Benefits [Abstract]
Employee benefit plans	Employee Benefit Plans Defined Benefit Plans The Company maintains multiple employee benefit plans. Certain of the Company’s employees in the UK were participants in a Siemen’s defined benefit plan established for employees of a UK-based operation acquired by Siemens in 2004. The plan was frozen with respect to future service credits for active employees, however the benefit formula recognized future compensation increases. The Company agreed to establish a replacement defined benefit plan, with the assets of the Siemens scheme transferring to the new scheme on April 1, 2015. Certain of the Company’s employees in Germany also participate in a defined benefit plan. Assets equaling the plan’s accumulated benefit obligation were transferred to a German defined benefit plan sponsored by the Company upon the acquisition of EWT from Siemens. The German entity also sponsors a defined benefit plan for a small group of employees located in France. The changes in projected benefit obligations, plan assets and the funded status of the UK and German defined benefit plans as of and for the years ended September 30, 2022 and 2021, respectively, are as follows: 2022 2021 Change in projected benefit obligation Projected benefit obligation at prior year measurement date $ 46,013 $ 47,389 Service cost 752 1,156 Interest cost 551 482 Actuarial gains (13,069) (2,312) Benefits paid from company assets (428) (738) Foreign currency exchange impact (7,165) 36 Projected benefit obligation at measurement date $ 26,654 $ 46,013 Change in plan assets Fair value of assets at prior year measurement date 28,638 27,530 Actual return on plan assets (4,639) 971 Benefits paid (109) (515) Employer contribution — 258 Foreign currency exchange impact (4,600) 394 Fair value of assets at measurement date $ 19,290 $ 28,638 Funded status and amount recognized in assets and liabilities $ (7,364) $ (17,375) Amount recognized in assets and liabilities Other non‑current assets $ 1,779 $ 2,960 Other non‑current liabilities $ (9,143) $ (20,335) Amount recognized in accumulated other comprehensive loss, before taxes Actuarial (gain) loss $ (1,067) $ 7,071 The following table provides summary information for the UK and German plans where the projected benefit obligation is in excess of plan assets: September 30, 2022 September 30, 2021 Projected benefit obligation $ 26,654 $ 46,013 Accumulated benefit obligation $ 14,621 $ 24,578 Fair value of plan assets $ 19,290 $ 28,638 The weighted average assumptions in the following table represent the rates used to develop the actuarial present value of the projected benefit obligation for the year indicated as well as net periodic pension cost for the following year. The discount rate is based on settling the obligation with high grade, high yield corporate bonds, and the rate of compensation increase is based upon actual experience. The expected return on assets is based on historical performance as well as expected future rates of return on plan assets considering the current investment portfolio mix and the long‑term investment strategy. 2022 2021 Discount rate 2.03% - 4.97% 1.00% - 2.03% Expected long‑term rate of return on plan assets 2.82% - 5.74% 1.97% - 3.50% Salary scale 2.25% - 4.54% 2.25% - 4.36% Pension increases 1.00% - 3.42% 1.00% - 3.27% The Plan trustees for the UK and German pension plans have established investment policies and strategies. The UK Pension Committee established and implemented a liability driven investment approach to take advantage of, and seeking to protect, its well‑funded status. The German investment strategy is to close the current funding gap by taking a risk-balanced growth approach through investing assets in marketable securities. Through a trust arrangement, the German plan assets are held in a global multi-asset fund. The actual overall asset allocation for the UK pension plan as compared to the investment policy goals as of September 30, 2022 was as follows by asset category: 2022 Actual 2022 Target Equity 26.7 % — % Index‑linked gilts 72.8 % 70 % Cash 0.5 % 30 % Pension expense for the German and UK plans were as follows: Year Ended September 30, 2022 2021 2020 Service cost $ 752 $ 1,156 $ 1,125 Interest cost 551 482 492 Expected return on plan assets (771) (615) (387) Amortization of actuarial losses 584 1,042 1,006 Pension expense for defined benefit plans $ 1,116 $ 2,065 $ 2,236 The components of pension expense, other than the service cost component, which is included in General and administrative expense, are included in the line item Other operating expense in the Consolidated Statements of Operations. Benefits expected to be paid to participants of the plans are as follows: Year Ended September 30, 2023 $ 880 2024 561 2025 648 2026 898 2027 828 Five years thereafter 7,616 Total $ 11,432 Defined Contribution Plans The Company maintains a defined contribution 401(k) plan, which covers all U.S.-based employees who meet minimum age and length of service requirements. Plan participants can elect to defer pre-tax compensation through payroll deductions. These deferrals are regulated under Section 401(k) of the Internal Revenue Code. Prior to January 1, 2021, the Company matched 100% of eligible participants’ deferrals that did not exceed 6% of their pay. Effective January 1, 2021, the Company matches 100% of eligible participants’ deferrals that do not exceed 4% of their pay. Also, effective January 1, 2021, the Company may make a discretionary profit sharing contribution of up to 4% of each plan participant’s compensation. All such contributions are subject to limitations imposed by the Internal Revenue Code. The Company’s total contributions were $21,448, $16,559, and $14,243 for the years ended September 30, 2022, 2021 and 2020, respectively. Employees in the UK and Germany also participate in a defined contribution plan maintained by the Company. For the years ended September 30, 2022, 2021 and 2020, contributions made to the Company’s plan in the UK and Germany were $937, $919, and $1,021, respectively. Deferred Compensation On April 1, 2014, the Company adopted a non-qualified deferred compensation plan for certain highly compensated employees. The Plan matches, on a dollar-for-dollar basis, up to the first 6% of a participant’s pay. The Company’s obligation under the plan represents an unsecured promise to pay benefits in the future. In the event of bankruptcy or insolvency of the Company, assets of the plan would be available to satisfy the claims of general creditors. To increase the security of the participants’ deferred compensation plan benefits, the Company has established and funded a grantor trust (known as a rabbi trust). The rabbi trust is specifically designed so that assets are available to pay plan benefits to participants in the event the Company is unwilling or unable to pay the plan benefits for any reason other than bankruptcy or insolvency. As a result, the Company is prevented from withdrawing or accessing assets for corporate needs. Plan participants choose to receive a return on their account balances equal to the return on the various investment options. The rabbi trust assets are primarily invested in mutual funds and insurance contracts of which the rabbi trust is the owner and beneficiary. Health Benefit Plan The Company maintains a qualified employee health benefit plan in the U.S. and is self‑funded by the Company with respect to claims up to a certain amount. The plan requires contributions from eligible employees and their dependents.

Income Taxes

Income Taxes	12 Months Ended
	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For financial reporting purposes, income (loss) before income taxes includes the following components: Year Ended September 30, 2022 2021 2020 Domestic $ 23,245 $ 19,927 $ 81,276 Foreign 46,068 41,815 40,490 Income before income taxes $ 69,313 $ 61,742 $ 121,766 The components of income tax (expense) benefit were as follows: Year Ended September 30, 2022 2021 2020 Current: Federal $ — $ — $ — State (932) (1,233) (591) Foreign (11,056) (11,210) (8,014) $ (11,988) $ (12,443) $ (8,605) Deferred: Federal 9,470 (2,153) 115 State 6,168 (630) 401 Foreign (620) 5,146 718 $ 15,018 $ 2,363 $ 1,234 Total income tax (expense) benefit $ 3,030 $ (10,080) $ (7,371) For the years ended September 30, 2022, 2021 and 2020, the U.S. federal statutory rate was 21.0%. A reconciliation of income tax (expense) benefit and the amount computed by applying the applicable statutory rate to income from operations before income taxes was as follows: Year Ended September 30, 2022 2021 2020 Income tax (expense) benefit at the federal statutory rate of 21% $ (14,556) $ (12,966) $ (25,571) State and local income taxes, net of federal tax benefit 989 (757) (74) Foreign tax rate differential (1,897) (3,009) (1,129) Nondeductible interest expense (578) (588) (1,032) Meals and entertainment expense (36) (176) (760) U.S. tax on foreign earnings (2,683) (5,687) (8,438) Other nondeductible expenses (2,952) (786) (479) Impact of tax rate changes (24) 819 286 Valuation allowances 17,087 854 19,013 Share-based compensation 6,990 11,598 4,931 Non-taxable gain on sale of subsidiary — — 4,789 Return-to-provision adjustments 1,790 (44) 516 Non-controlling interest 31 30 (466) Net benefit of foreign R&D expenses — — 18 Transaction related contingent liabilities 824 155 143 Deferred tax adjustments (2,317) 87 491 Accrued tax adjustments (138) 27 (6) Other 500 363 397 Total $ 3,030 $ (10,080) $ (7,371) Annual Tax (Expense) Benefit For the year ended September 30, 2022, tax benefit was $3,030 as compared to tax expense based on the U.S. statutory rate of $14,556. The actual tax benefit was lower principally due to a one-time reversal of the U.S. federal and state valuation allowance which was partially offset by an increase in foreign tax expense due to improved profitability in certain jurisdictions with tax rates higher than the U.S. See the above reconciliation for more detail. Tax expense decreased $13,110 to a benefit of $3,030 for the year ended September 30, 2022 as compared to tax expense of $10,080 in the prior year. The decrease in tax expense was primarily attributable to a one-time reversal of the U.S. federal and state valuation allowance which was partially offset by an increase in foreign tax expense due to improved profitability in certain jurisdictions with tax rates higher than the U.S. Tax expense increased $2,709 to $10,080 for the year ended September 30, 2021 as compared to $7,371 in the prior year. The increase in tax expense was primarily attributable to an increase in foreign tax expense due to improved profitability in certain countries and the impact of a one-time state tax adjustment for prior periods. The increase in expense was partially offset by a one-time tax benefit for the reversal of the valuation allowance with respect to the Company’s German operating company. Significant components of deferred tax assets and liabilities were as follows: September 30, 2022 September 30, 2021 Deferred Tax Assets Receivable allowances $ 1,619 $ 885 Reserves and accruals 23,706 24,913 Inventory valuation and other assets 4,196 3,141 Investment in partnership — 1,977 Unrealized foreign exchange gains (losses), including related hedges 8,573 4,468 Right of use liabilities 12,021 — Other deferred tax assets 1,052 2,811 Net operating loss carryforwards 40,124 48,605 Gross deferred tax assets $ 91,291 $ 86,800 Less: Valuation allowance (3,740) (21,299) Deferred tax assets less valuation allowance $ 87,551 $ 65,501 Deferred Tax Liabilities Goodwill (8,162) (9,849) Fixed assets (48,992) (46,057) Intangibles (15,359) (15,313) Deferred tax liabilities in other comprehensive income (12,360) — Right of use assets (11,291) — Other deferred tax liabilities (1,751) (2,440) Gross deferred tax liabilities $ (97,915) $ (73,659) Net deferred tax liabilities $ (10,364) $ (8,158) The Company performs an evaluation at the end of each reporting period to determine whether it is more likely than not that all or some portion of our deferred tax assets will not be realized in future years. In making such a determination, the Company considers available positive and negative evidence, including (i) future reversal of existing taxable temporary differences, (ii) tax planning strategies, (iii) the carryforward periods of tax losses, (vi) recent results of operations, and (v) projected future taxable income. In performing this evaluation in prior periods, a full valuation allowance was recorded as a result of objective negative evidence which included losses generated in five of the six years ended September 30, 2014 to September 30, 2019 and the associated limitation on our ability to consider subjective evidence such as projections of future growth and profitability. As of September 30, 2022, the Company has generated profit each of the last three fiscal years while dealing with significant operational and worldwide economic challenges. As a result, we are able to take into consideration future projected income as part of our analysis. Based upon the available positive and negative evidence and the weight accorded to that evidence on September 30, 2022, the Company has determined that the significant positive evidence outweighs the negative evidence. Therefore, the Company has concluded that it is more likely than not that the U.S. federal and state deferred tax assets will be realized and accordingly will no longer provide a valuation allowance against those deferred tax assets. The previously provided valuation allowances have been released. The valuation allowances that remain relate to certain foreign net operating losses and credits that are not expected to be realized. A reconciliation of the valuation allowance on deferred tax assets is as follows: Year Ended September 30, 2022 2021 2020 Valuation allowance beginning of period $ 21,299 $ 23,298 $ 41,084 Change in assessment (17,305) (6,140) 1,650 Current year operations 217 7,300 (19,856) Foreign currency and other (471) (3,219) 3,012 Acquisitions / Dispositions — 60 (2,592) Valuation allowance end of period $ 3,740 $ 21,299 $ 23,298 The Company does not anticipate that it will dispose any of its foreign subsidiaries in the foreseeable future and as such has not recorded a U.S. deferred tax asset where the tax basis exceeds the financial reporting basis of these investments. Additionally, the Company has not provided a U.S. deferred tax liability on the excess of financial reporting over tax basis of its investments. As of September 30, 2022, 2021 and 2020, undistributed earnings of non-U.S. affiliates were approximately $119,524, $77,709, and $53,766, respectively, which are considered to be indefinitely reinvested. Upon distribution of these earnings the Company may be subject to U.S. income taxes and foreign withholding taxes. The amount of taxes that may be payable on remittance of these earnings is dependent on the tax laws and profile of the Company at that time and the availability of foreign tax credits in the year in which such earnings are remitted. Therefore, it is not practicable to estimate the amount of taxes that may be payable when these earnings are remitted in the future. The Company utilizes the more-likely-than-not standard in recognizing a tax benefit in its financial statements. For the years ended September 30, 2022, 2021, and 2020, the Company had unrecognized tax benefits of $1,035, $1,123, and $1,050 respectively. The following is a reconciliation of the Company’s total gross unrecognized tax benefits: Year Ended September 30, 2022 2021 2020 Balance as of beginning of period $ 1,123 $ 1,050 $ 1,075 Tax positions related to the current year Additions — — — Tax positions related to prior years Additions — 73 — Reductions (88) — (25) Expiration of statutes of limitations — — — Balance as of end of period $ 1,035 $ 1,123 $ 1,050 At September 30, 2022, 2021, and 2020, the Company had $1,593, $1,599, and $1,288 classified as a current liability respectively. The amount of unrecognized tax benefits is not expected to change significantly during the next 12 months. At September 30, 2022, 2021, and 2020, if the Company’s tax positions are sustained by the taxing authorities in favor of the Company, the amount that would affect the Company’s effective tax rate would be approximately $1,593, $1,599, and $1,288 respectively. The Company classifies interest expense and, if applicable, penalties which could be assessed related to unrecognized tax benefits as component of income tax (expense) benefit. For the years ended September 30, 2022, 2021, and 2020 the Company recognized approximately $(81), $(238), and $(143) of gross interest and penalties, respectively. Tax attributes available to reduce future taxable income begin to expire as follows: September 30, 2022 Begin Expiring Federal net operating loss $ 156,887 September 30, 2035 State net operating loss 78,348 September 30, 2023 State tax credits 43 September 30, 2036 Foreign net operating loss 2,121 September 30, 2023 Foreign net operating loss 8,644 Indefinite During the fourth quarter of the year ending September 30, 2020 the Company undertook a secondary offering. As a result of that offering, the Company experienced an ownership change for purposes of I.R.C. Section 382. There was no impact to current or deferred tax expense resulting from the ownership change for the years ending September 30, 2022, 2021 and 2020. The Company may be subject to tax audits in the U.S. as well as various state and foreign jurisdictions. The following table summarizes the Company’s open years by major jurisdiction as of September 30, 2022: Jurisdiction Open Tax Years United States 2019-2022 Australia 2018-2022 Canada 2018-2022 China 2017-2022 Germany 2018-2022 Netherlands 2017-2022 Singapore 2018-2022 United Kingdom 2020-2022

Share Based Compensation

Share Based Compensation	12 Months Ended
	Sep. 30, 2022
Share-Based Payment Arrangement [Abstract]
Share Based Compensation	Share-Based Compensation The Company designs equity compensation plans to attract and retain employees while also aligning employees’ interests with the interests of the Company’s shareholders. In addition, members of the Company’s Board of Directors (the “Board”) participate in equity compensation plans in connection with their service on the Company’s Board. The Company established the Evoqua Water Technologies Corp. Stock Option Plan (the “Stock Option Plan”) shortly after the acquisition date of January 16, 2014 . The plan allows certain management employees and the Board to purchase shares in Evoqua Water Technologies Corp. Under the Stock Option Plan, the number of shares available for award was 11,083. As of September 30, 2022, there were approximately 2,177 shares available for future grants, however, the Company does not currently intend to make additional grants under the Stock Option Plan. In connection with the IPO, the Board adopted and the Company’s shareholders approved the Evoqua Water Technologies Corp. 2017 Equity Incentive Plan (or the “Equity Incentive Plan”), under which equity awards may be granted in the form of options, restricted stock, restricted stock units, stock appreciation rights, dividend equivalent rights, share awards and performance-based awards (including performance share units and performance-based restricted stock). During the year ended September 30, 2022, the Company granted RSUs, stock appreciation rights, and performance share units under the Equity Incentive Plan to certain employees of the Company as well as its Board of Directors. The final number of performance share units that may be earned is dependent on the Company’s achievement of performance goals related to cumulative revenue growth dollars and average adjusted EBITDA margin over a three-year measurement period ending September 30, 2024, in which the maximum payout cannot exceed 250% of the applicable target award, which also considers that the final number of performance share units that may be earned is subject to a total stockholder return (“TSR”) modifier, which operates by increasing or decreasing the total number of shares earned by up to 25% based on the Company’s TSR relative to the TSR of the U.S. constituents of the S&P Global Water Index. In order to receive shares earned at the end of the performance period, the recipient must remain employed by the Company or its subsidiaries through the end of the three As of September 30, 2022, there were approximately 3,977 shares available for grants under the Equity Incentive Plan. Option awards vest ratably at 25% per year, and are exercisable at the time of vesting. The options granted have a ten A summary of the stock option activity, including stock appreciation rights, for the years ended September 30, 2022 and 2021 is presented below: (In thousands, except per share amounts) Options Weighted Average Exercise Price/Share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding at September 30, 2020 7,430 $ 10.30 5.9 years $ 83,152 Granted 612 $ 24.78 Exercised (2,884) $ 6.81 Forfeited (67) $ 21.25 Cancelled (1) $ 16.63 Outstanding at September 30, 2021 5,090 $ 13.87 5.9 years $ 120,611 Granted 2 $ 46.75 Exercised (789) $ 8.86 Forfeited (38) $ 21.05 Outstanding at September 30, 2022 4,265 $ 14.74 5.2 years $ 78,218 Options exercisable at September 30, 2022 3,223 $ 12.51 4.4 years $ 66,272 Options vested and expected to vest at September 30, 2022 4,253 $ 14.72 5.2 years $ 78,093 The total intrinsic value of options exercised (which is the amount by which the stock price exceeded the exercise price of the options of the date of exercise) during the year ended September 30, 2022 was $24,919. During the year ended September 30, 2022, $9,556 was received from the exercise of stock options. A summary of the status of the Company's nonvested stock options, including stock appreciation rights, as of and for the years ended September 30, 2022, 2021 and 2020 is presented below. 2022 2021 2020 (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Shares Weighted Average Grant Date Fair Value/Share Shares Weighted Average Grant Date Fair Value/Share Unvested at beginning of period 1,901 $ 6.69 2,166 $ 5.56 2,379 $ 4.96 Granted 2 $ 24.22 612 $ 9.00 823 $ 6.06 Vested (823) $ 6.54 (810) $ 5.48 (864) $ 4.52 Forfeited (38) $ 6.87 (67) $ 6.82 (172) $ 4.94 Unvested at end of period 1,042 $ 6.82 1,901 $ 6.69 2,166 $ 5.56 The total fair value of options vested during the year was $5,382, $4,434, and $3,906 for the years ended September 30, 2022, 2021 and 2020, respectively. Restricted Stock Units The following is a summary of the RSU activity for the years ended September 30, 2022 and 2021. Shares Weighted Average Grant Date Fair Value/Share Outstanding at September 30, 2020 750 $ 17.86 Granted 731 $ 25.98 Vested (240) $ 17.55 Forfeited (25) $ 20.31 Cancelled (7) $ 21.22 Outstanding at September 30, 2021 1,209 $ 22.77 Granted 328 $ 44.88 Vested (507) $ 22.23 Forfeited (50) $ 27.96 Outstanding at September 30, 2022 980 $ 30.18 Expected to vest at September 30, 2022 959 $ 30.05 Performance Share Units The following is a summary of the PSU activity for the years ended September 30, 2022 and 2021. (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Unvested at September 30, 2020 — $ — Granted 469 $ 16.92 Nonvested at September 30, 2021 469 $ 16.92 Granted 124 $ 52.50 Forfeited (1) $ 47.92 Nonvested at September 30, 2022 592 $ 23.36 Expected to vest at September 30, 2022 555 $ 23.25 Expense Measurement and Recognition The Company recognizes share-based compensation for all current award grants and, in future periods, will recognize compensation costs for the unvested portion of previous award grants based on grant date fair values as well as expectations for achievement of performance goals. Total share-based compensation expense was $23,450, $17,703 and $10,535 during the year ended September 30, 2022, 2021 and 2020, respectively, of which $22,104, $15,524 and $10,509 was non-cash, respectively. Reported non-cash share-based compensation expense was classified on the Consolidated Statements of Operations as shown in the following table: Year Ended September 30, 2022 2021 2020 Cost of services $ 234 $ 143 $ 91 General and administrative 21,870 15,381 10,418 $ 22,104 $ 15,524 $ 10,509 The unrecognized compensation expense related to stock options, RSUs, and and performance share units (measured at a target award level) was $4,655, $20,255 and $9,710, respectively at September 30, 2022, and is expected to be recognized over a weighted average period of 1.4 years, 1.7 years, and 1.8 years, respectively. The Company estimates the fair value of each stock option and stock appreciation right awards on the grant date using the Black-Scholes valuation model incorporating the assumptions noted in the following table. Option valuation models require the input of highly subjective assumptions, and changes in assumptions used can materially affect the fair value estimate. Valuation assumptions for options and stock appreciation rights granted are as follows for the years ended September 2022, 2021 and 2020, respectively: Year Ended September 30, 2022 2021 2020 Expected volatility 55.3% 38.3% - 56.7% 24.2% - 77.1% Expected dividends — — — Expected term (in years) 5.9 5.3 - 6.0 5.4 - 6.0 Risk free rate 1.4% 0.4% - 0.9% 0.2% - 1.7% Grant date fair value per share of options and stock appreciation rights granted $24.22 $8.12 - $19.76 $5.33 - $8.56 The risk‑free interest rate is based on the U.S. treasury security rate in effect as of the date of grant. Beginning in fiscal year 2021, the Company utilized historical realized volatility for expected volatility which is based on historical stock prices during a period of time. Prior to fiscal year 2021, the Company had little history with respect to volatility of share prices, and as such, the expected volatility was not based on realized volatility. The Company, as permitted under ASC 718, had identified guideline public companies who are participants in the Company’s markets. The Company obtained share price trading data from the guideline companies and based their estimate of expected volatility on the implied volatility of the guideline companies in addition to the Company’s own implied volatility. As the guideline companies were comparable in most significant respects, the Company believed they represent an appropriate basis for estimating expected volatility. For performance share units, the performance metrics in the units are valued using the grant-date fair value. The market conditions in the units are valued using an estimated fair value on the grant date using a Monte Carlo simulation incorporating the assumptions noted in the following table. Year Ended September 30, 2022 2021 Expected volatility 56.0% - 56.2% 61.0% Expected dividends — — Expected term (in years) 3.0 3.0 Risk free rate 0.91% - 1.13% 0.34% Grant date fair value per share of PSUs granted $46.08 - $52.57 $16.92 The risk‑free interest rate is based on the U.S. treasury security rate in effect as of the date of grant. The Company utilized historical realized volatility for expected volatility which is based on historical stock prices during a period of time. Employee Stock Purchase Plan Effective October 1, 2018, the Company implemented an employee stock purchase plan (the “ESPP”) which allows employees to purchase shares of the Company’s stock at 85% of the lower of the fair market value on the first or last business day of the applicable six-month offering period. These purchases are offered twice throughout each fiscal year, and are paid by employees through payroll deductions over the respective six month purchase period, at the end of which the stock is transferred to the employees. On December 21, 2018, the Company registered 11,297 shares of common stock, par value $0.01 per share, of which 5,000 are available for future issuance under the ESPP. During the years ended September 30, 2022, 2021 and 2020, the Company incurred compensation expense of $1,011, $887 and $392, respectively, in salaries and wages in respect of the ESPP, representing the fair value of the discounted price of the shares. These amounts are included in the total share-based compensation expense above. During the years ended September 30, 2022, 2021 and 2020, 108 shares, 182 shares and 58 shares, respectively, were issued under the ESPP plan.

Other Comprehensive Loss

Other Comprehensive Loss	12 Months Ended
	Sep. 30, 2022
Equity [Abstract]
Other Comprehensive Loss	Other Comprehensive Income (Loss) The components of accumulated other comprehensive income (loss) were: September 30, 2022 September 30, 2021 Foreign currency translation income $ 6,767 $ 16,137 Pension benefit plans, net of tax expense of $2,790 and $403 (1,776) (7,474) Unrealized derivative gain on cash flow hedges, net of tax expense of $11,770 and $135 37,940 2,752 Total accumulated other comprehensive income $ 42,931 $ 11,415 The (losses) gains in accumulated other comprehensive income (loss) by component, net of tax, for the years ended September 30, 2022, 2021 and 2020 are as follows: Foreign currency Pension Cash flow Hedges Balance at September 30, 2019 $ (2,705) $ (10,475) $ 176 Other comprehensive loss before reclassifications (2,830) (927) (5,375) Amounts gains reclassified from accumulated other comprehensive loss into earnings — 1,006 658 Balance at September 30, 2020 $ (5,535) $ (10,396) $ (4,541) Other comprehensive income before reclassifications 21,672 1,880 4,909 Amounts gains reclassified from accumulated other comprehensive loss into earnings — 1,042 2,384 Balance at September 30, 2021 $ 16,137 $ (7,474) $ 2,752 Other comprehensive (loss) income before reclassifications (9,370) 5,114 35,975 Amounts gains (losses) reclassified from accumulated other comprehensive loss (income) into earnings — 584 (787) Balance at September 30, 2022 $ 6,767 $ (1,776) $ 37,940 Amounts reclassified out of other comprehensive income (loss) related to the amortization of actuarial losses are included in pension expense. Refer to Note 13, “Derivative Financial Instruments” for the location in the Consolidated Statements of Operations of amounts reclassified out of other comprehensive income (loss) related to cash flow hedges.

Concentration of Credit Risk

Concentration of Credit Risk	12 Months Ended
	Sep. 30, 2022
Risks and Uncertainties [Abstract]
Concentration of Credit Risk	Concentration of Credit Risk The Company’s cash and cash equivalents and accounts receivable are potentially subject to concentration of credit risk. Cash and cash equivalents are placed with financial institutions that management believes are of high credit quality. Accounts receivable is derived from revenue earned from customers located in the U.S. and internationally and generally do not require collateral. The Company’s trade receivables do not represent a significant concentration of credit risk at September 30, 2022 and 2021 due to the wide variety of customers and markets into which products are sold and their dispersion across geographic areas. The Company does perform ongoing credit evaluations of its customers and maintains an allowance for potential credit losses on trade receivables. As of and for the years ended September 30, 2022, 2021 and 2020, no customer accounted for more than 10% of net sales or net accounts receivable. The Company operates predominantly in nine countries worldwide and provides a wide range of proven product brands and advanced water and wastewater treatment technologies, mobile and emergency water supply solutions and service contract options through its Integrated Solutions and Services and Applied Product Technologies segments. The Company is a multi-national business, but its sales and operations are primarily in the U.S. External sales to unaffiliated customers are transacted with the Company location that maintains the customer relationship. The following tables set forth external net revenue, net of intercompany eliminations, and net asset information by region: Year Ended September 30, 2022 2021 2020 Sales to external customers United States $ 1,431,095 $ 1,174,474 $ 1,164,634 Rest of World 305,981 289,955 264,822 Total $ 1,737,076 $ 1,464,429 $ 1,429,456 September 30, 2022 September 30, 2021 Net Assets United States $ 558,512 $ 462,883 Rest of World 151,581 119,336 $ 710,093 $ 582,219 Long Lived Assets United States $ 388,591 $ 357,597 Rest of World 16,698 17,391 $ 405,289 $ 374,988

Leases

Leases	12 Months Ended
	Sep. 30, 2022
Leases [Abstract]
Lessee, Operating Leases [Text Block]	Leases Lessee Accounting The following represents the components of lease cost for the years ended September 30, 2022, 2021, and 2020 and other information for both operating and finance leases for the years ended September 30, 2022, 2021, and 2020: Year Ended September 30, 2022 2021 2020 Lease cost Finance lease cost: Amortization of ROU assets $ 13,461 $ 13,572 $ 13,738 Interest on lease liabilities 1,574 1,793 1,981 Operating lease cost 16,529 15,357 16,052 Short-term lease cost 875 2,935 4,970 Sublease income — (58) (56) Total lease cost $ 32,439 $ 33,599 $ 36,685 Year Ended September 30, Other information 2022 2021 2020 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from finance leases $ 1,573 $ 1,810 $ 1,968 Operating cash flows from operating leases $ 17,178 $ 15,758 $ 16,034 Financing cash flows from finance leases $ 13,356 $ 13,373 $ 13,459 ROU assets obtained in exchange for new finance lease liabilities $ 15,329 $ 14,257 $ 14,934 ROU assets obtained in exchange for new operating lease liabilities $ 14,151 $ 4,839 $ 8,456 ROU asset remeasurement $ 6,723 $ 8,177 $ (960) Weighted average remaining lease term - finance leases 3.5 years 3.6 years 3.9 years Weighted average remaining lease term - operating leases 4.6 years 4.8 years 5.2 years Weighted average discount rate - finance leases 4.2 % 4.3 % 4.6 % Weighted average discount rate - operating leases 4.2 % 4.0 % 4.2 % The following table reconciles future minimum undiscounted rental commitments for operating leases to operating lease liabilities record on the Consolidated Balance Sheet as of September 30, 2022: Fiscal Year 2023 $ 16,995 2024 14,927 2025 12,585 2026 9,345 2027 5,815 Thereafter 4,788 Total undiscounted lease payments $ 64,455 Present value adjustment (5,562) Operating lease liabilities $ 58,893 Less current installments of obligations under operating leases 14,932 Obligations under operating leases, excluding current installments $ 43,961 The gross and net carrying values of the equipment under finance leases as of September 30, 2022 and September 30, 2021 was as follows: September 30, 2022 September 30, 2021 Gross carrying amount $ 85,217 $ 92,247 Net carrying amount $ 37,715 $ 36,884 The following table reconciles future minimum undiscounted rental commitments for finance leases to the finance lease liabilities recorded on the Consolidated Balance Sheet as of September 30, 2022: Fiscal Year 2023 $ 14,220 2024 11,669 2025 8,674 2026 5,132 2027 1,938 Thereafter 209 Total undiscounted lease payments $ 41,842 Present value adjustment (2,779) Finance lease liabilities $ 39,063 Less current installments of obligations under finance leases 12,875 Obligations under finance leases, excluding current installments $ 26,188 The current installments of obligations under finance leases are included in Accrued expenses and other liabilities. Obligations under finance leases, excluding current installments, are included in Other non-current liabilities. Lessor Accounting The following represents the components of lease revenue for the years ended September 30, 2022, 2021, and 2020: Year Ended September 30, 2022 2021 2020 Lease revenue: operating leases $ 164,574 $ 152,435 $ 148,703 Lease revenue: sales-type leases 16,937 37,898 981 Total lease revenue $ 181,511 $ 190,333 $ 149,684 As of September 30, 2022, future minimum lease payments receivable under operating leases are as follows: Fiscal year 2023 $ 165,025 2024 99,403 2025 69,620 2026 46,650 2027 34,700 Thereafter 181,314 Future minimum lease payments $ 596,712 At September 30, 2022, the Company had current and long-term lease receivables of $3,001 and $51,482, respectively, recorded in Prepaid and other current assets and Other non‑current assets, respectively, in the Consolidated Balance Sheets related to sales-type leases. As of September 30, 2022, the maturities of the Company’s sales type lease receivables are as follows: Fiscal year 2023 $ 3,001 2024 4,128 2025 4,128 2026 4,128 2027 4,128 Thereafter 34,970 Total $ 54,483
Lessor, Operating Leases [Text Block]	Leases Lessee Accounting The following represents the components of lease cost for the years ended September 30, 2022, 2021, and 2020 and other information for both operating and finance leases for the years ended September 30, 2022, 2021, and 2020: Year Ended September 30, 2022 2021 2020 Lease cost Finance lease cost: Amortization of ROU assets $ 13,461 $ 13,572 $ 13,738 Interest on lease liabilities 1,574 1,793 1,981 Operating lease cost 16,529 15,357 16,052 Short-term lease cost 875 2,935 4,970 Sublease income — (58) (56) Total lease cost $ 32,439 $ 33,599 $ 36,685 Year Ended September 30, Other information 2022 2021 2020 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from finance leases $ 1,573 $ 1,810 $ 1,968 Operating cash flows from operating leases $ 17,178 $ 15,758 $ 16,034 Financing cash flows from finance leases $ 13,356 $ 13,373 $ 13,459 ROU assets obtained in exchange for new finance lease liabilities $ 15,329 $ 14,257 $ 14,934 ROU assets obtained in exchange for new operating lease liabilities $ 14,151 $ 4,839 $ 8,456 ROU asset remeasurement $ 6,723 $ 8,177 $ (960) Weighted average remaining lease term - finance leases 3.5 years 3.6 years 3.9 years Weighted average remaining lease term - operating leases 4.6 years 4.8 years 5.2 years Weighted average discount rate - finance leases 4.2 % 4.3 % 4.6 % Weighted average discount rate - operating leases 4.2 % 4.0 % 4.2 % The following table reconciles future minimum undiscounted rental commitments for operating leases to operating lease liabilities record on the Consolidated Balance Sheet as of September 30, 2022: Fiscal Year 2023 $ 16,995 2024 14,927 2025 12,585 2026 9,345 2027 5,815 Thereafter 4,788 Total undiscounted lease payments $ 64,455 Present value adjustment (5,562) Operating lease liabilities $ 58,893 Less current installments of obligations under operating leases 14,932 Obligations under operating leases, excluding current installments $ 43,961 The gross and net carrying values of the equipment under finance leases as of September 30, 2022 and September 30, 2021 was as follows: September 30, 2022 September 30, 2021 Gross carrying amount $ 85,217 $ 92,247 Net carrying amount $ 37,715 $ 36,884 The following table reconciles future minimum undiscounted rental commitments for finance leases to the finance lease liabilities recorded on the Consolidated Balance Sheet as of September 30, 2022: Fiscal Year 2023 $ 14,220 2024 11,669 2025 8,674 2026 5,132 2027 1,938 Thereafter 209 Total undiscounted lease payments $ 41,842 Present value adjustment (2,779) Finance lease liabilities $ 39,063 Less current installments of obligations under finance leases 12,875 Obligations under finance leases, excluding current installments $ 26,188 The current installments of obligations under finance leases are included in Accrued expenses and other liabilities. Obligations under finance leases, excluding current installments, are included in Other non-current liabilities. Lessor Accounting The following represents the components of lease revenue for the years ended September 30, 2022, 2021, and 2020: Year Ended September 30, 2022 2021 2020 Lease revenue: operating leases $ 164,574 $ 152,435 $ 148,703 Lease revenue: sales-type leases 16,937 37,898 981 Total lease revenue $ 181,511 $ 190,333 $ 149,684 As of September 30, 2022, future minimum lease payments receivable under operating leases are as follows: Fiscal year 2023 $ 165,025 2024 99,403 2025 69,620 2026 46,650 2027 34,700 Thereafter 181,314 Future minimum lease payments $ 596,712 At September 30, 2022, the Company had current and long-term lease receivables of $3,001 and $51,482, respectively, recorded in Prepaid and other current assets and Other non‑current assets, respectively, in the Consolidated Balance Sheets related to sales-type leases. As of September 30, 2022, the maturities of the Company’s sales type lease receivables are as follows: Fiscal year 2023 $ 3,001 2024 4,128 2025 4,128 2026 4,128 2027 4,128 Thereafter 34,970 Total $ 54,483

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Guarantees From time to time, the Company is required to provide letters of credit, bank guarantees, or surety bonds in support of its commitments and as part of the terms and conditions on water treatment projects. In addition, the Company is required to provide letters of credit or surety bonds to the department of environmental protection or equivalent in some states in order to maintain its licenses to handle toxic substances at certain of its water treatment facilities. These financial instruments typically expire after all Company commitments have been met, a period typically ranging from twelve months to ten years, or more in some circumstances. The letters of credit, bank guarantees, or surety bonds are arranged through major banks or insurance companies. In the case of surety bonds, the Company generally indemnifies the issuer for all costs incurred if a claim is made against the bond. The following summarizes the Company’s outstanding letters of credit and surety bonds as of September 30, 2022 and September 30, 2021, respectively. September 30, 2022 September 30, 2021 Revolving credit capacity $ 60,000 $ 60,000 Letters of credit outstanding 9,317 10,112 Remaining revolving credit capacity $ 50,683 $ 49,888 Surety capacity $ 261,959 $ 250,000 Surety issuances 134,037 147,845 Remaining surety available $ 127,922 $ 102,155 The longest maturity date of letters of credit and surety bonds in effect as of September 30, 2022 was March 20, 2030. Litigation From time to time, as a normal incident of the nature and kind of business in which the Company is engaged, various claims or charges are asserted and litigation commenced against it arising from or related to product liability; personal injury; trademarks, trade secrets or other intellectual property; labor and employee disputes; commercial or contractual disputes; breach of warranty; or environmental matters. Claimed amounts may be substantial but may not bear any reasonable relationship to the merits of the claim or the extent of any real risk of court or arbitral awards. While it is not feasible to predict the outcome of these matters with certainty, and some lawsuits, claims or proceedings may be disposed or decided unfavorably, the Company does not expect that any asserted or un-asserted legal claims or

Accrued Expenses and Other Liab

Accrued Expenses and Other Liabilities	12 Months Ended
	Sep. 30, 2022
Payables and Accruals [Abstract]
Accrued Expenses and Other Liabilities	Accrued Expenses and Other Liabilities Accrued expenses and other liabilities consisted of the following: September 30, September 30, Salaries, wages, and other benefits $ 83,618 $ 79,110 Obligation under operating leases 14,932 13,316 Obligation under finance leases 12,875 12,093 Third party commissions 10,341 10,031 Deferred revenue 9,692 5,241 Taxes, other than income 5,594 4,575 Insurance liabilities 3,456 3,720 Provisions for litigation 2,375 2,938 Fair value of liability derivatives 1,511 554 Severance payments 658 304 Earn-outs related to acquisitions — 150 Other 33,220 28,335 $ 178,272 $ 160,367

Business Segments

Business Segments	12 Months Ended
	Sep. 30, 2022
Segment Reporting [Abstract]
Business segments	Business Segments The Company’s reportable operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated on a regular basis by the chief operating decision maker, or decision making group, in deciding how to allocate resources to an individual segment and in assessing performance. The key factors used to identify these reportable operating segments are the organization and alignment of the Company’s internal operations, the nature of the products and services, and customer type. The Company has two reportable operating segments, Integrated Solutions and Services and Applied Product Technologies. The business segments are described as follows: Integrated Solutions and Services is a group entirely focused on engaging directly with end users through direct sales with a market vertical focus. Integrated Solutions and Services provides tailored services and solutions in collaboration with the customers backed by life‑cycle services including on‑demand water, outsourced water, recycle / reuse, and emergency response service alternatives to improve operational reliability, performance, and environmental compliance. Key offerings within this segment also include equipment systems for industrial needs (influent water, boiler feed water, ultrahigh purity, process water, wastewater treatment and recycle / reuse), full-scale outsourcing of operations and maintenance, and municipal services, including odor and corrosion control services. Applied Product Technologies is focused on developing product platforms to be sold primarily through third party channels. This segment primarily engages in indirect sales through independent sales representatives, distributors, and aftermarket channels. Applied Product Technologies provides a range of highly differentiated and scalable products and technologies specified by global water treatment designers, OEMs, engineering firms, and integrators. Key offerings within this segment include filtration and separation, disinfection, wastewater solutions, anode and electrochlorination technology, and aquatics technologies and solutions for the global recreational and commercial pool market. Corporate activities include general corporate expenses, elimination of intersegment transactions, interest income and expense and certain other charges. Certain other charges may include restructuring and other business transformation charges that have been undertaken to align and reposition the Company to the current reporting structure, acquisition related costs (including transaction costs and certain integration costs), and share-based compensation charges. Since certain administrative costs and other operating expenses have not been allocated to business segments, the results in the below table are not necessarily a measure computed in accordance with generally accepted accounting principles and may not be comparable to other companies. The tables below provide segment information for the periods presented and a reconciliation to total consolidated information: Year Ended September 30, 2022 2021 2020 Total sales Integrated Solutions and Services $ 1,222,165 $ 980,852 $ 954,542 Applied Product Technologies 653,245 588,080 559,635 Total sales $ 1,875,410 $ 1,568,932 $ 1,514,177 Intersegment sales Integrated Solutions and Services $ 37,688 $ 20,966 $ 10,360 Applied Product Technologies 100,646 83,537 74,361 Total intersegment sales $ 138,334 $ 104,503 $ 84,721 Sales to external customers Integrated Solutions and Services $ 1,184,477 $ 959,886 $ 944,182 Applied Product Technologies 552,599 504,543 485,274 Total sales $ 1,737,076 $ 1,464,429 $ 1,429,456 Income from operations Integrated Solutions and Services $ 165,562 $ 147,251 $ 145,655 Applied Product Technologies 103,087 82,891 134,258 Corporate (164,656) (130,825) (111,465) Total income from operations $ 103,993 $ 99,317 $ 168,448 Interest expense (34,680) (37,575) (46,682) Income before income taxes $ 69,313 $ 61,742 $ 121,766 Income tax benefit (expense) 3,030 (10,080) (7,371) Net income $ 72,343 $ 51,662 $ 114,395 Depreciation and amortization Integrated Solutions and Services $ 83,866 $ 70,585 $ 67,489 Applied Product Technologies 13,918 14,423 14,226 Corporate 29,786 28,656 25,553 Total depreciation and amortization $ 127,570 $ 113,664 $ 107,268 Capital expenditures Integrated Solutions and Services $ 66,897 $ 60,407 $ 75,551 Applied Product Technologies 6,704 6,955 6,237 Corporate 8,444 7,931 6,668 Total Capital expenditures $ 82,045 $ 75,293 $ 88,456 September 30, 2022 September 30, 2021 Assets Integrated Solutions and Services $ 1,123,166 $ 887,265 Applied Product Technologies 653,244 656,362 Corporate 414,453 325,264 Total assets $ 2,190,863 $ 1,868,891 Goodwill Integrated Solutions and Services $ 306,935 $ 233,830 Applied Product Technologies 166,637 173,546 Total goodwill $ 473,572 $ 407,376

Earnings Per Share

Earnings Per Share	12 Months Ended
	Sep. 30, 2022
Earnings Per Share [Abstract]
Earnings per share	Earnings Per Share The following table sets forth the computation of basic and diluted income from continuing operations per common share: Year Ended September 30, (In thousands, except per share data) 2022 2021 2020 Numerator: Net income attributable to Evoqua Water Technologies Corp. $ 72,198 $ 51,482 $ 113,649 Denominator: Denominator for basic net income per common share—weighted average shares 121,138 119,575 116,721 Effect of dilutive securities: Share‑based compensation 3,744 3,368 4,342 Denominator for diluted net loss per common share—adjusted weighted average shares 124,882 122,943 121,063 Basic income per common share $ 0.60 $ 0.43 $ 0.97 Diluted income per common share $ 0.58 $ 0.42 $ 0.94 Because of their anti-dilutive effect, 474, 1,784, and 2,512 common share equivalents, comprised of employee stock options, have been excluded from the diluted EPS calculation for the years ended September 30, 2022, 2021, and 2020, respectively.

Subsequent Events

Subsequent Events	12 Months Ended
	Sep. 30, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsNone.

SCHEDULE_I - Evoqua Water Techn

SCHEDULE I - Evoqua Water Technologies Corp.	12 Months Ended
	Sep. 30, 2022
Condensed Financial Information Disclosure [Abstract]
Condensed Financial Information of Parent Company Only Disclosure	SCHEDULE I-Evoqua Water Technologies Corp. (Parent company only) Condensed Consolidated Balance Sheets (In thousands) September 30, 2022 September 30, 2021 ASSETS Current assets $ 67,403 $ 51,777 Due from affiliates 62,080 39,982 Cash and cash equivalents 5,202 11,681 Prepaid and other current assets 121 114 Investment in affiliate 600,064 517,479 Total assets $ 667,467 $ 569,256 LIABILITIES AND EQUITY Other current liabilities 305 — Total liabilities $ 305 $ — Common stock, par value $0.01: authorized 1,000,000 shares; issued 123,411 shares, outstanding 121,747 at September 30, 2022; issued 122,173 shares, outstanding 120,509 at September 30, 2021 1,235 1,223 Treasury stock: 1,664 shares at September 30, 2022 and 1,664 shares at September 30, 2021 (2,837) (2,837) Additional paid‑in capital 607,748 582,052 Retained earnings (deficit) 61,016 (11,182) Total shareholders’ equity $ 667,162 $ 569,256 Total liabilities and shareholder’s equity $ 667,467 $ 569,256 SCHEDULE I-Evoqua Water Technologies Corp. (Parent company only) Condensed Statements of Operations (In thousands) Year Ended September 30, 2022 2021 2020 Other operating income (expense) $ 8 $ (1,073) $ 16 General and administrative expense (454) (426) (476) Net income of subsidiaries 72,644 52,981 114,109 Income before taxes 72,198 51,482 113,649 Benefit for income taxes — — — Net income $ 72,198 $ 51,482 $ 113,649 SCHEDULE 1-Evoqua Water Technologies Corp. Condensed Statements of Cash Flows (Parent company only) (In thousands) Year Ended September 30, 2022 2021 2020 Operating activities Net income $ 72,198 $ 51,482 $ 113,649 Adjustments to reconcile net income (loss) to net cash used in operating activities Net income of subsidiaries (72,644) (52,981) (114,109) Foreign currency exchange gains on intercompany loans — — (15) Changes in assets and liabilities Due from affiliates (9,606) (11,638) 5,842 Due to affiliates — — (9,747) Accrued expenses 305 — 160 Prepaids and other current assets (7) (36) (24) Net cash used in operating activities $ (9,754) $ (13,173) $ (4,244) Investing activities Contributed capital $ — $ — $ — Net cash used in investing activities $ — $ — $ — Financing activities Proceeds from issuance of common stock $ 9,556 $ 21,205 $ 18,927 Taxes paid related to net share settlements of share-based compensation awards (6,281) (1,323) (9,832) Net cash provided by financing activities $ 3,275 $ 19,882 $ 9,095 Change in cash and cash equivalents $ (6,479) $ 6,709 $ 4,851 Cash and cash equivalents Beginning of period 11,681 4,972 121 End of period $ 5,202 $ 11,681 $ 4,972 SCHEDULE I-Evoqua Water Technologies Corp. (Parent company only) Notes to Financial Statements (In thousands) 1. Basis of Presentation Basis of Presentation In the parent‑company‑only financial statements, the Company’s investment in subsidiaries is stated at cost plus equity in undistributed earnings of subsidiaries. The Company’s share of net income (loss) of its consolidated subsidiaries is included in consolidated income (loss) using the equity method. The parent‑company‑only financial statements should be read in conjunction with the Company’s consolidated financial statements. 2. Guarantees and Restrictions On April 1, 2021, EWT Holdings III Corp. (“EWT III”), a subsidiary of the Company, entered into a Credit Agreement (the “2021 Credit Agreement”) among EWT III, as borrower, EWT Holdings II Corp. (“EWT II”), as parent guarantor, the lenders from time to time party thereto, JPMorgan Chase Bank, N.A., as administrative agent and collateral agent, and ING Capital, LLC, as sustainability coordinator. The 2021 Credit Agreement provides for a multi-currency senior secured revolving credit facility in an aggregate principal amount not to exceed the U.S. dollar equivalent of $350,000 (the “2021 Revolving Credit Facility”) and a discounted senior secured term (the “2021 Term Loan”) in the amount of $475,000 (together with the 2021 Revolving Credit Facility, the “Senior Facilities”). The Senior Facilities are guaranteed by EWT II and certain existing and future direct or indirect wholly-owned domestic subsidiaries of EWT III (together with EWT III, collectively, the “Loan Parties”), and collateralized by a first lien on substantially all of the assets of the Loan Parties, with certain exceptions. In connection with entering into the 2021 Credit Agreement, on April 1, 2021, EWT III repaid all outstanding indebtedness under the 2014 Credit Agreement and terminated that facility. As of September 30, 2022 and September 30, 2021, EWT III had $620,317 and $511,105, respectively, of debt outstanding under the Senior Facilities. Under the terms of the credit agreements governing the Company’s senior secured credit facilities, EWT II has guaranteed the payment of all principal and interest. In the event of a default under our senior secured credit facilities, certain of the Company’s subsidiaries will be directly liable to the debt holders. The 2021 Term Loan matures on April 1, 2028. Subject to the terms of the 2021 Credit Agreement, to the extent not previously paid, any amount owed under the 2021 Revolving Credit Facility will become due and payable in full on April 1, 2026. The credit agreements governing the Company’s senior secured credit facilities also include restrictions on the ability of the Company and its subsidiaries to (i) incur additional indebtedness and liens in connection therewith; (ii) pay dividends and make certain other restricted payments; (iii) effect mergers or consolidations; (iv) enter into transactions with affiliates; (v) sell or dispose of property or assets; and (vi) engage in unrelated lines of business. 3. Dividends from Subsidiaries There were no cash dividends paid to Evoqua Water Technologies Corp. from the Company’s consolidated subsidiaries of each of the periods ended September 30, 2022, 2021 and 2020.

Accounting Policies (Policies)

Accounting Policies (Policies)	12 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) from the accounting records of the Company and reflect the consolidated financial position and results of operations for the fiscal years ended September 30, 2022, 2021 and 2020. Unless otherwise specified, references in this section to a year refer to its fiscal year. All intercompany transactions have been eliminated. Unless otherwise specified, all dollar and share amounts in this section are referred to in thousands. Certain prior period amounts have been reclassified to conform to the current period presentation. The Company’s fiscal year ends on September 30 of each year and references in this section to a year refer to the Company’s fiscal year. As such, references to: 2022 relates to the fiscal year ended September 30, 2022, 2021 relates to the fiscal year ended September 30, 2021 and 2020 relates to the fiscal year ended September 30, 2020.
Fiscal Year	Fiscal YearThe Company’s fiscal year ends on September 30.
Use of Estimates	Use of Estimates The Consolidated Financial Statements have been prepared in conformity with GAAP and require management to make estimates and assumptions. These assumptions affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the audited Consolidated Financial Statements and the reported amounts of revenue and expenses during the reporting period. Estimates and assumptions are used for, but not limited to: (i) revenue recognition; (ii) allowance for credit losses; (iii) inventory valuation, asset valuations, impairment, and recoverability assessments; (iv) depreciable lives of assets; (v) useful lives of intangible assets; (vi) income tax reserves and valuation allowances; and (vii) product warranty and litigation reserves. Estimates are revised as additional information becomes available. Actual results could differ from these estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents are liquid investments with an original maturity of three or fewer months when purchased.
Accounts Receivable	Accounts Receivable Receivables are primarily comprised of uncollected amounts owed to the Company from transactions with customers and are reported on the Consolidated Balance Sheets at the outstanding principal amount adjusted for any allowance for credit losses and any charge offs. The Company provides an allowance for credit losses to reduce trade receivables to their estimated net realizable value equal to the amount that is expected to be collected. This allowance is estimated based on historical collection experience, the aging of receivables, specific current and expected future macroeconomic and market conditions, and assessments of the current creditworthiness and economic status of customers. The Company considers a receivable delinquent if it is unpaid after the term of the related invoice has expired. Write‑offs are recorded at the time all collection efforts have been exhausted. The Company reviews its allowance for credit losses on a quarterly basis.
Inventories	Inventories Inventories are stated at the lower of cost or net realizable value, where cost is generally determined on the basis of an average or first‑in, first‑out (“FIFO”) method. Production costs comprise direct material and labor and applicable manufacturing overheads, including depreciation charges. The Company regularly reviews inventory quantities on hand and writes off excess or obsolete inventory based on estimated forecasts of product demand and production requirements. Manufacturing operations recognize cost of product sales using standard costing rates with overhead absorption which generally approximates actual cost.
Property, Plant and Equipment	Property, Plant, and Equipment Property, plant, and equipment is valued at cost less accumulated depreciation. Depreciation expense is recognized using the straight‑line method. Useful lives are reviewed annually and, if expectations differ from previous estimates, adjusted accordingly. Estimated useful lives for major classes of depreciable assets are as follows: Asset Class Estimated Useful Life Machinery and equipment 3 to 20 years Buildings and improvements 10 to 40 years Leasehold improvements are depreciated over the shorter of their estimated useful life or the term of the lease. Costs related to maintenance and repairs that do not extend the assets’ useful life are expensed as incurred.
Acquisitions	Acquisitions The Company evaluates the inputs, processes and outputs of each asset acquired to determine if the transaction meets the definition of a business in accordance with Accounting Standards Codification (“ASC”) Topic No. 805, Business Combinations (“ASC 805”). Acquisitions that do not meet the definition of a business are accounted for as an asset acquisition. In asset acquisitions, the Company allocates the purchase price as well as other costs of acquisition, such as transaction costs, to tangible and identifiable intangible assets or liabilities based on the basis of relative fair values. This cost accumulation model is unique to asset acquisitions and differs from business combinations as there is no goodwill recognized. Acquisitions that meet the definition of a business are recorded using the acquisition method of accounting. The purchase price of acquisitions is allocated to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair value at the acquisition date. The excess of the acquisition price over those estimated fair values is recorded as goodwill. Changes to the acquisition date preliminary fair values prior to the expiration of the measurement period, a period not to exceed 12 months from date of acquisition, are recorded as an adjustment to the associated goodwill. Contingent consideration resulting from acquisitions is recorded at its estimated fair value on the acquisition date. These obligations are revalued during each subsequent reporting period and changes in the fair value of the contingent consideration obligations can result from adjustments in the probability of achieving future development
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill represents purchase consideration paid in a business combination that exceeds the value assigned to the net assets of acquired businesses. Intangible assets consist of customer‑related intangibles, proprietary technology, software, trademarks, and other intangible assets. The Company amortizes intangible assets with definite useful lives on a straight‑line basis over their respective estimated economic lives which range from 1 to 26 years. The Company reviews goodwill and indefinite-lived intangible assets to determine potential impairment annually during the fourth quarter of its fiscal year, or more frequently if events and circumstances indicate that the asset might be impaired. Impairment testing for goodwill is performed at a reporting unit level and the Company has determined that it has three reporting units. The quantitative impairment testing for goodwill utilizes both a market (guideline public company) and income (discounted cash flows) method for determining fair value. In estimating the fair value of the reporting unit utilizing a discounted cash flow (“DCF”) valuation technique, the Company incorporates its judgment and estimates of future cash flows, future revenue and gross profit growth rates, terminal value amount, capital expenditures and applicable weighted‑average cost of capital used to discount these estimated cash flows. The estimates and projections used in the estimate of fair value are consistent with the Company’s current budget and long‑range plans, including anticipated change in market conditions, industry trend, growth rates and planned capital expenditures, among other considerations.
Impairment of Long‑Lived Assets	Impairment of Long‑Lived Assets Long‑lived assets, such as property, plant, and equipment, purchased intangibles and lease right-of-use assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. Recoverability of the asset or asset group is measured by comparison of its carrying amount to undiscounted future net cash flows the asset or asset group is expected to generate. If the carrying amount of an asset or asset group is not recoverable, the Company recognizes an impairment loss based on the excess of the carrying amount of the asset or asset group over its respective fair value which is generally determined as the present value of estimated future cash flows or as the appraised value.
Debt Issuance Costs And Debt Discounts	Debt Issuance Costs and Debt Discounts Debt issuance costs are capitalized and amortized over the contractual term of the underlying debt using the effective interest method. Debt discounts and lender arrangement fees deducted from the proceeds have been included as a component of the carrying value of debt and are being amortized to interest expense using the effective interest method.
Revenue Recognition	Revenue Recognition The Company recognizes sales of products and services based on the five-step analysis of transactions as provided in Topic 606, Revenue from Contracts with Customers. For sales of aftermarket parts or products with a low level of customization and engineering time, the Company recognizes revenue at the time risks and rewards of ownership pass, which is generally when products are shipped or delivered to the customer as the Company has no obligation for installation. The Company considers shipping and handling services to be fulfillment activities and as such they do not represent separate performance obligations for revenue recognition. Sales of short‑term service arrangements are recognized as the services are performed, and sales of long‑term service arrangements are typically recognized on a straight‑line basis over the life of the agreement. For certain arrangements where there is significant customization to the product and for long-term construction-type sales contracts, revenue may be recognized over time. These arrangements include large capital water treatment projects, systems, and solutions for municipal and industrial applications. The nature of the contracts is generally fixed price with milestone billings. Contract revenue and cost estimates are reviewed and revised quarterly at a minimum and the cumulative effect of such adjustments are recognized in current operations. The amount of such adjustments has not been material. Contract assets relate to costs incurred to perform in advance of scheduled billings. Contract liabilities relate to payments received in advance of performance under the contracts. Change in contract assets and liabilities are due to the Company’s performance under the contract. The Company has made accounting policy elections to exclude all taxes by governmental authorities from the measurement of the transaction price and that long-term construction-type sales contracts, or those contracts for products with significant customization that the total contract price is less than $100 will be recorded at the point in time when the construction is complete. The recording of assets recognized from the costs to obtain and fulfill customer contracts primarily relate to the deferral of sales commissions. The Company’s costs incurred to obtain or fulfill a contract with a customer are classified as non-current assets and amortized to expense over the period of benefit of the related revenue. These costs are recorded within Cost of product sales and services. The amount of contract costs was insignificant at September 30, 2022. The Company offers standard warranties that generally do not represent a separate performance obligation. In certain instances, a warranty is obtained separately from the original equipment sale or the warranty provides incremental services and as such is treated as a separate performance obligation.
Product Warranties	Product Warranties Accruals for estimated expenses related to warranties are made at the time products are sold and are recorded as a component of Cost of product sales in the Consolidated Statements of Operations. The estimated warranty obligation is based on product warranty terms offered to customers, ongoing product failure rates, material usage and service delivery costs expected to be incurred in correcting a product failure, as well as specific obligations for known failures and other currently available evidence. The Company assesses the adequacy of the recorded warranty liabilities on a regular basis and adjusts amounts as necessary. The Company accrues warranty obligations associated with certain products as revenue is recognized. Provisions for the warranty obligations are based upon historical experience of costs incurred for such obligations, adjusted for site‑specific risk factors, and, as necessary, for current conditions and factors. There are significant uncertainties and judgments involved in estimating warranty obligations, including changing product designs, differences in customer installation processes and future claims experience which may vary from historical claims experience.
Lessee Accounting	Leases The Company accounts for leases in accordance with ASC Topic No. 842, Leases . Lessee Accounting The Company leases office space, buildings, vehicles, forklifts, computers, copiers and other assets under non-cancelable operating and finance leases. The Company determines whether an arrangement is or contains a lease at the inception of the arrangement based on the terms and conditions in the contract. A contract contains a lease if there is an identified asset and the Company has the right to control the asset. If the arrangement contains a lease, the Company recognizes a right-of-use (“ROU”) asset and an operating lease liability as of the lease commencement date. Any lease arrangements with a term of 12 months or less are not recorded on the Consolidated Balance Sheets, and lease costs for these arrangements are recognized on a straight-line basis over the lease term. Many of the Company’s lease arrangements provide for an option to exercise one or more renewal terms or to terminate the lease arrangement. The Company includes these options when the Company is reasonably certain to exercise them in the leased term used to establish the ROU asset and lease liabilities. The discount rate utilized in calculating the lease liability is the rate implicit in the lease, if known, otherwise, the incremental borrowing rate (“IBR”) for the expected lease term is used.
Lessor Accounting	Lessor Accounting The Company generates revenue through the lease of its water treatment equipment and systems to customers. In certain instances, the Company enters into a contract with a customer but must construct the underlying asset prior to its lease. At the time of contract inception, the Company determines if an arrangement is or contains a lease. These contracts generally contain both lease and non-lease components, including installation, maintenance, and monitoring services of the Company-owned equipment, in addition to sale of certain constructed assets. In situations where arrangements contain multiple elements, contract consideration is allocated based on relative standalone selling price. Lease components associated with underlying assets that have an alternative use are classified as operating leases with revenue recognized over time throughout the lease term. Lease components associated with underlying assets that have no alternative are classified as sales-type leases, with point in time revenue recognition at the on-set of the lease, or classified as financing transactions, with over time revenue recognition at the on-set of the construction of the underlying assets. In order for a component to be separate, the customer would be able to benefit from the right of use of the component separately or with other resources readily available to the customer and the right of the use is not highly dependent or highly interrelated with the other rights to use the other underlying assets or components.
Shipping and Handling Cost	Shipping and Handling Cost Shipping and handling costs are included as a component of Cost of product sales.
Derivative Financial Instruments	Derivative Financial Instruments The Company’s risk-management strategy uses derivative financial instruments to manage interest rate risk, foreign currency exchange rate risk, equity price risk and commodity price risk. The Company does not enter into derivatives for trading or speculative purposes. The Company accounts for derivatives and hedging activities in accordance with ASC Topic No. 815, Derivatives and Hedging (“Topic No. 815”). As required by Topic No. 815, the Company records all derivatives on the Consolidated Balance Sheets at fair value and adjusts to market on a quarterly basis. Changes in the fair value of derivatives are recorded in earnings or Accumulated other comprehensive income, net of tax (“AOCI”), based on whether the instrument is designated and effective as a hedge transaction. Gains and losses on derivative instruments recorded to AOCI are reclassified to earnings in the period the hedged item affects earnings.
Income Taxes	Income Taxes The Company recognizes deferred tax assets and liabilities for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Valuation allowances are provided against deferred tax assets when it is considered more likely than not that some portion or all of the deferred tax asset will not be realized within a reasonable time period. The Company assesses tax positions using a two‑step process. A tax position is recognized if it meets a more‑likely‑than‑not threshold and is measured at the largest amount of benefit that has a greater than 50% percent likelihood of being realized. Uncertain tax positions are reviewed each balance sheet date.
Foreign Currency Translation and Transactions	Foreign Currency Translation and Transactions The functional currency for the international subsidiaries is the local currency. Assets and liabilities are translated into U.S. dollars using current rates of exchange, with the resulting translation adjustments recorded in Accumulated other comprehensive income, net of tax within shareholders’ equity. Revenue and expenses are translated at the weighted‑average exchange rate for the period, with the resulting translation adjustments recorded in the Consolidated Statements of Operations.
Research and Development Costs	Research and Development CostsResearch and development costs are expensed as incurred.
Equity-based Compensation	Equity‑based Compensation The Company measures the cost of awards of equity instruments to employees based on the grant‑date fair value of the award. The grant‑date fair value of a non-qualified stock option is determined using the Black‑Scholes model. The grant-date fair value of restricted stock unit awards is determined using the closing price of the Company’s common stock on date of grant. For performance share units, performance metrics are valued using the grant-date fair value and the market conditions are valued using a Monte Carlo simulation. Compensation costs resulting from equity-based payment transactions are recognized primarily within General and administrative expenses, at fair value over the requisite vesting period on a straight-line basis.
Earnings (Loss) Per Share	Earnings (Loss) Per Share Basic earnings (loss) per common share is computed based on the weighted average number of shares of common stock outstanding during the period. Diluted earnings per common share is computed based on the weighted average number of shares of common stock, plus the effect of diluted common shares outstanding during the period using the treasury stock method. Diluted potential common shares include outstanding stock options.
Retirement Benefits	Retirement Benefits The Company applies ASC Topic 715, Compensation—Retirement Benefits , which requires the recognition in pension obligations and accumulated other comprehensive income of actuarial gains or losses, prior service costs or credits and transition assets or obligations that have previously been deferred. The determination of retirement benefit pension obligations and associated costs requires the use of actuarial computations to estimate participant plan benefits to which
Recent Accounting Pronouncements	Recent Accounting Pronouncements Accounting Pronouncements Not Yet Adopted In September 2022, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2022-04, Liabilities—Supplier Finance Programs (Subtopic 405-50): Disclosure of Supplier Finance Program Obligations , which enhances transparency about an entity’s use of supplier finance programs by requiring quarterly and annual disclosures about the key terms of the program, outstanding confirmed amounts as of the end of the period, a rollforward of such amounts annually, and a description of where in the financial statements outstanding amounts are presented. The guidance is effective for fiscal years beginning after December 15, 2022. The Company is currently assessing the impact of adoption on the Company’s Consolidated Financial Statements and related disclosures. In October 2021, the “FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers , which amends Accounting Standards Codification (“ASC”) 805 to require an acquirer to, at the date of acquisition, recognize and measure contract assets and contract liabilities acquired in accordance with ASU 2014-09, Revenue from Contracts with Customers (Topic 606) (“Topic 606”) , as if the entity had originated the contracts, rather than adjust them to fair value at the acquisition date. The guidance is effective for fiscal years beginning after December 15, 2022 and is to be applied prospectively to business combinations occurring on or after the effective date of the amendments. The Company is currently assessing the impact of adoption on the Company’s Consolidated Financial Statements and related disclosures. Accounting Pronouncements Recently Adopted In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting , and also issued subsequent amendments to the initial guidance (collectively, “Topic 848”). Topic 848 became effective immediately and expires on December 31, 2022. Topic 848 allows eligible contracts that are modified to be accounted for as a continuation of those contracts, permits companies to preserve their hedge accounting during the transition period and enables companies to make a one-time election to transfer or sell held-to-maturity debt securities that are affected by rate reform. Topic 848 provides optional expedients and exceptions for contracts, hedging relationships and other transactions that reference the London Inter-Bank Offered Rate (“LIBOR”) or another reference rate expected to be discontinued because of reference rate reform if certain criteria are met. The Company adopted Topic 848 during the year ended September 30, 2022 and the adoption did not have a material impact on the Company’s Consolidated Financial Statements and related disclosures.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Schedule Of Estimated Useful Lives For Major Classes Of Depreciable Assets	Estimated useful lives for major classes of depreciable assets are as follows: Asset Class Estimated Useful Life Machinery and equipment 3 to 20 years Buildings and improvements 10 to 40 years Property, plant, and equipment consists of the following: September 30, 2022 September 30, 2021 Machinery and equipment $ 401,334 $ 388,352 Rental equipment 267,345 246,257 Land and buildings 82,985 70,048 Construction in process 72,184 59,737 $ 823,848 $ 764,394 Less: accumulated depreciation (418,559) (389,406) Property, plant, and equipment, net $ 405,289 $ 374,988 Depreciation expense and maintenance and repairs expense for the years ended September 30, 2022, 2021 and 2020 were as follows: Year Ended September 30, 2022 2021 2020 Depreciation expense $ 82,637 $ 76,279 $ 73,002 Maintenance and repair expense $ 30,425 $ 22,354 $ 20,303

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Variable Interest Entities	The following provides a summary of TWO’s balance sheet as of September 30, 2021 and summarized financial information for the fiscal years ended September 30, 2022, 2021 and 2020. As a result of the acquisition of the remaining partnership interest in TWO on April 1, 2022, there is no summarized balance sheet as of September 30, 2022. September 30, Current assets (includes cash of $1,380) $ 3,202 Property, plant, and equipment 903 Goodwill 2,206 Total liabilities (1,009) Year Ended September 30, 2022 2021 2020 Total revenue $ 1,641 $ 3,315 $ 5,944 Total operating expenses (1,440) (2,922) (4,519) Income from operations $ 201 $ 393 $ 1,425 The following provides a summary of Frontier’s balance sheet as of September 30, 2021, and summarized financial information for the fiscal years ended September 30, 2022, 2021 and 2020. As a result of the acquisition of the remaining equity interest in Frontier on April 1, 2022, there is no summarized balance sheet as of September 30, 2022. September 30, Current assets (includes cash of $2,095) $ 12,495 Property, plant, and equipment 2,113 Goodwill 1,798 Intangible assets, net 8,265 Total liabilities (9,425) Year Ended September 30, 2022 2021 2020 Total revenue $ 13,363 $ 14,340 $ 5,365 Total operating expenses (12,135) (14,362) (8,219) Income (loss) from operations $ 1,228 $ (22) $ (2,854)

Acquisitions and Divestitures (

Acquisitions and Divestitures (Tables)	12 Months Ended
	Sep. 30, 2022
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The opening balance sheet for WCSI is summarized as follows: Current assets $ 1,813 Property, plant, and equipment 221 Goodwill 4,340 Intangible assets, net 7,336 Other non-current assets 86 Total assets acquired $ 13,796 Liabilities assumed $ (1,792) Net assets acquired $ 12,004 The opening balance sheet for Ultrapure is summarized as follows: Current assets $ 2,366 Property, plant, and equipment 963 Goodwill 2,836 Intangible assets, net 3,751 Other non-current assets 21 Total assets acquired $ 9,937 Liabilities assumed $ (904) Net assets acquired $ 9,033

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Sep. 30, 2022
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	Information regarding the source of revenue: Year Ended September 30, 2022 2021 2020 Revenue from contracts with customers recognized under Topic 606 $ 1,555,565 $ 1,274,096 $ 1,279,772 Other (1) 181,511 190,333 149,684 Total $ 1,737,076 $ 1,464,429 $ 1,429,456 (1) Other revenue relates to revenue recognized pursuant to ASU 2016-02, Leases (Topic 842) , primarily attributable to long term rentals. Information regarding revenue disaggregated by segment and source of revenue is as follows: Year Ended September 30, 2022 2021 2020 Integrated Solutions and Services Revenue from capital projects $ 304,925 $ 250,187 $ 257,528 Revenue from aftermarket 215,972 128,585 119,051 Revenue from service 663,580 581,114 567,603 Total $ 1,184,477 $ 959,886 $ 944,182 Applied Product Technologies Revenue from capital projects $ 383,473 $ 365,791 $ 335,227 Revenue from aftermarket 148,118 116,463 128,051 Revenue from service 21,008 22,289 21,996 Total $ 552,599 $ 504,543 $ 485,274 Total Revenue Revenue from capital projects $ 688,398 $ 615,978 $ 592,755 Revenue from aftermarket 364,090 245,048 247,102 Revenue from service 684,588 603,403 589,599 Total $ 1,737,076 $ 1,464,429 $ 1,429,456
Schedule of Revenue from External Customers by Geographic Areas	Information regarding revenue disaggregated by geographic area is as follows: Year Ended September 30, 2022 2021 2020 United States $ 1,431,095 $ 1,174,474 $ 1,164,634 Asia 129,981 113,316 77,253 Europe 108,271 113,559 108,139 Canada 54,935 49,952 65,223 Australia 12,794 13,128 14,207 Total $ 1,737,076 $ 1,464,429 $ 1,429,456 The following tables set forth external net revenue, net of intercompany eliminations, and net asset information by region: Year Ended September 30, 2022 2021 2020 Sales to external customers United States $ 1,431,095 $ 1,174,474 $ 1,164,634 Rest of World 305,981 289,955 264,822 Total $ 1,737,076 $ 1,464,429 $ 1,429,456
Contract with Customer, Asset and Liability	The tables below provide a roll-forward of contract assets and contract liabilities balances for the periods presented: Year Ended September 30, Contract assets (a) 2022 2021 Balance at beginning of period $ 72,746 $ 80,759 Recognized in current period 401,825 316,864 Reclassified to accounts receivable (368,936) (325,405) Foreign currency (3,512) 528 Balance at end of period $ 102,123 $ 72,746 (a) Excludes receivable balances which are disclosed on the Consolidated Balance Sheets. Year Ended September 30, Contract Liabilities 2022 2021 Balance at beginning of period $ 55,883 $ 26,259 Recognized in current period 370,375 349,046 Amounts in beginning balance reclassified to revenue (44,313) (25,523) Current period amounts reclassified to revenue (319,513) (294,033) Foreign currency 7 134 Balance at end of period $ 62,439 $ 55,883

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table presents the Company’s financial assets and liabilities at fair value. The fair values related to the pension assets are determined using net asset value (“NAV”) as a practical expedient, or by information categorized in the fair value hierarchy level based on the inputs used to determine fair value. The reported carrying amounts of deferred compensation assets and liabilities and debt approximate their fair values. The Company uses interest rates and other relevant information generated by market transactions involving similar instruments to measure the fair value of these assets and liabilities, therefore, all are classified as Level 2 within the valuation hierarchy. Net Asset Value Quoted Market Significant Other Significant As of September 30, 2022 Assets: Pension plan Cash $ — $ 40 $ — $ — Global Multi-Asset Fund 11,632 — — — Government Securities 3,343 — — — Liability Driven Investment 928 — — — Guernsey Unit Trust 2,048 — — — Global Absolute Return 1,299 — — — Deferred compensation plan assets Cash — 902 — — Mutual Funds — 12,330 — — Earn-out assets related to acquisitions — — — 11,597 Interest rate swaps — — 49,952 — Foreign currency forward contracts — — 507 — Liabilities: Pension plan — — (26,654) — Deferred compensation plan liabilities — — (20,081) — Total return swaps—deferred compensation — — (632) — Long‑term debt — — (884,517) — Foreign currency forward contracts — — (872) — Commodity swaps — — (7) — As of September 30, 2021 Assets: Pension plan Cash $ — $ 831 $ — $ — Global Multi-Asset Fund 15,244 — — — Government Securities 5,158 — — — Liability Driven Investment 2,793 — — — Guernsey Unit Trust 2,387 — — — Global Absolute Return 2,225 — — — Deferred compensation plan assets Cash — 1,251 — — Mutual Funds — 17,806 — — Interest rate swaps — — 3,127 — Foreign currency forward contracts — — 24 — Liabilities: Pension plan — — (46,013) — Deferred compensation plan liabilities — — (24,382) — Total return swaps—deferred compensation — — (130) — Long‑term debt — — (752,988) — Interest rate swaps — — (303) — Foreign currency forward contracts — — (102) — Commodity swaps — — (19) — Earn-out liabilities related to acquisitions — — — (150) Purchase Right — — — (8,305)
Schedule of Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	A rollforward of the activity in the Company’s fair value of earn-out liabilities related to acquisitions is as follows: Current Portion (1) Long-term Portion (2) Total Balance at September 30, 2020 $ 295 $ — $ 295 Acquisitions 761 — 761 Payments (170) — (170) Fair value adjustment (736) — (736) Balance at September 30, 2021 $ 150 $ — $ 150 Fair value adjustment (150) — (150) Balance at September 30, 2022 $ — $ — $ — (1) Included in Accrued expenses and other liabilities on the Consolidated Balance Sheets. (2) Included in Other non‑current liabilities on the Consolidated Balance Sheets.

Accounts Receivable (Tables)

Accounts Receivable (Tables)	12 Months Ended
	Sep. 30, 2022
Receivables [Abstract]
Schedule of accounts receivable	Accounts receivable are summarized as follows: September 30, 2022 September 30, 2021 Accounts Receivable $ 312,600 $ 282,819 Allowance for Credit Losses (6,888) (4,824) Receivables, net $ 305,712 $ 277,995 The movement in the allowance for credit losses was as follows: Year Ended September 30, 2022 2021 2020 Balance at beginning of period $ (4,824) $ (4,057) $ (4,906) Charged to costs and expenses (1,997) (1,733) (537) Write-offs 473 780 1,277 Foreign currency and other (540) 186 109 Balance at end of period $ (6,888) $ (4,824) $ (4,057)

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Sep. 30, 2022
Inventory Disclosure [Abstract]
Schedule of Inventory	The major classes of inventory, net are as follows: September 30, 2022 September 30, 2021 Raw materials and supplies $ 120,532 $ 86,469 Work in progress 36,499 19,842 Finished goods and products held for resale 80,811 59,624 Costs of unbilled projects 2,309 2,277 Reserves for excess and obsolete (10,800) (9,709) Inventories, net $ 229,351 $ 158,503
Schedule of Activity in Reserves for Excess and Obsolete Inventory	The following is the activity in the reserves for excess and obsolete inventory: Year Ended September 30, 2022 2021 2020 Balance at beginning of period $ (9,709) $ (11,467) $ (13,370) Change to reserve requirement (2,608) 265 (310) Write-offs 684 1,516 2,197 Foreign currency and other 833 (23) 16 Balance at end of period $ (10,800) $ (9,709) $ (11,467)

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	12 Months Ended
	Sep. 30, 2022
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Estimated useful lives for major classes of depreciable assets are as follows: Asset Class Estimated Useful Life Machinery and equipment 3 to 20 years Buildings and improvements 10 to 40 years Property, plant, and equipment consists of the following: September 30, 2022 September 30, 2021 Machinery and equipment $ 401,334 $ 388,352 Rental equipment 267,345 246,257 Land and buildings 82,985 70,048 Construction in process 72,184 59,737 $ 823,848 $ 764,394 Less: accumulated depreciation (418,559) (389,406) Property, plant, and equipment, net $ 405,289 $ 374,988 Depreciation expense and maintenance and repairs expense for the years ended September 30, 2022, 2021 and 2020 were as follows: Year Ended September 30, 2022 2021 2020 Depreciation expense $ 82,637 $ 76,279 $ 73,002 Maintenance and repair expense $ 30,425 $ 22,354 $ 20,303
Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block]	The Company entered into secured financing agreements that require providing a security interest in specified equipment. As of September 30, 2022 and September 30, 2021, the gross and net amounts of those assets are as follows: September 30, 2022 September 30, 2021 Gross Net Gross Net Machinery and equipment $ 86,294 $ 62,459 $ 73,632 $ 57,036 Construction in process 49,983 49,983 30,504 30,504 $ 136,277 $ 112,442 $ 104,136 $ 87,540

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Changes in the carrying amount of goodwill are as follows: Integrated Solutions and Services Applied Product Technologies Total Balance at September 30, 2020 $ 224,381 $ 172,824 $ 397,205 Business combinations and divestitures 10,349 — 10,349 Measurement period adjustments (3,216) — (3,216) Foreign currency translation 2,316 722 3,038 Balance at September 30, 2021 $ 233,830 $ 173,546 $ 407,376 Business combinations and divestitures 76,190 (34) $ 76,156 Measurement period adjustments 379 — 379 Foreign currency translation (3,464) (6,875) (10,339) Balance at September 30, 2022 $ 306,935 $ 166,637 $ 473,572

Other Intangible Assets (Tables

Other Intangible Assets (Tables)	12 Months Ended
	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	Intangible assets consist of the following: September 30, 2022 Estimated Life (years) Carrying Amount Accumulated Amortization Net Amortizing intangible assets Customer related 3 - 26 $ 346,128 $ (122,604) $ 223,524 Proprietary technology 4 - 10 68,586 (44,532) 24,054 Trademark 3 - 15 32,711 (15,056) 17,655 Backlog 1 81,159 (81,159) — Other 3 - 10 57,719 (39,426) 18,293 Total amortizing intangible assets $ 586,303 $ (302,777) $ 283,526 Indefinite‑lived intangible assets 34,207 — 34,207 Total intangible assets $ 620,510 $ (302,777) $ 317,733 September 30, 2021 Estimated Life (years) Carrying Amount Accumulated Amortization Net Amortizing intangible assets Customer related 5 - 26 $ 300,963 $ (101,272) $ 199,691 Proprietary technology 7 - 10 61,692 (36,921) 24,771 Trademark 5 - 15 27,195 (12,191) 15,004 Backlog 1 82,355 (82,355) — Other 3 - 10 47,903 (31,501) 16,402 Total amortizing intangible assets $ 520,108 $ (264,240) $ 255,868 Indefinite‑lived intangible assets 34,207 — 34,207 Total intangible assets $ 554,315 $ (264,240) $ 290,075
Schedule of Finite-lived Intangible Assets Amortization Expense	For the amortizing intangible assets, the remaining weighted-average amortization period at September 30, 2022 was as follows: Years Customer-related intangibles 8 Proprietary technology 3 Trademarks 6 Other 3 Aggregate net intangible assets 6
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The estimated future amortization expense is as follows: 2023 $ 44,421 2024 38,994 2025 33,960 2026 28,596 2027 24,070 Thereafter 113,485 Total $ 283,526

Debt (Tables)

Debt (Tables)	12 Months Ended
	Sep. 30, 2022
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Long‑term debt consists of the following: September 30, September 30, 2021 Term Loan, due April 1, 2028 $ 469,063 $ 473,837 2021 Revolving Credit Facility, due April 1, 2026 151,254 37,268 Securitization Facility, due April 1, 2024 150,201 150,061 Equipment Financing, due September 30, 2023 to September 30, 2032, interest rates ranging from 3.59% to 8.07% 120,155 93,375 Notes Payable, due July 31, 2023 (1) — 402 Total debt $ 890,673 $ 754,943 Less unamortized deferred financing fees (9,873) (11,738) Total net debt $ 880,800 $ 743,205 Less current portion (17,266) (12,775) Total long‑term debt $ 863,534 $ 730,430 (1) In March 2022, the outstanding balance of the Notes Payable due July 31, 2023, was repaid in conjunction with the Company’s acquisition of TWO. See Note 4, “Acquisitions and Divestitures” for further discussion.
Schedule of Credit Facilities	The following table summarizes the amount of the Company’s outstanding borrowings and outstanding letters of credit under the 2021 Revolving Credit Facility as of September 30, 2022, and September 30, 2021. September 30, September 30, Borrowing availability $ 350,000 $ 350,000 Outstanding borrowings 151,000 37,000 Outstanding letters of credit 9,317 10,112 Unused amounts $ 189,683 $ 302,888 The following summarizes the Company’s outstanding letters of credit and surety bonds as of September 30, 2022 and September 30, 2021, respectively. September 30, 2022 September 30, 2021 Revolving credit capacity $ 60,000 $ 60,000 Letters of credit outstanding 9,317 10,112 Remaining revolving credit capacity $ 50,683 $ 49,888 Surety capacity $ 261,959 $ 250,000 Surety issuances 134,037 147,845 Remaining surety available $ 127,922 $ 102,155
Schedule of Equipment Financings	During the year ended September 30, 2022, the Company completed the following equipment financings: Date Entered Due Interest Rate at September 30, 2022 Principal Amount September 30, 2022 September 30, 2032 5.30 % $ 3,811 September 29, 2022 May 31, 2029 (1) 5.03 % 2,248 June 30, 2022 July 31, 2029 (2) 6.31 % 12,356 June 30, 2022 May 31, 2029 (1) 5.03 % 4,086 March 18, 2022 March 17, 2029 4.67 % 1,839 March 16, 2022 July 31, 2029 (2) 6.31 % 1,317 March 15, 2022 April 1, 2029 4.67 % 4,788 December 30, 2021 December 30, 2028 3.94 % 2,207 December 23, 2021 July 31, 2029 (2) 6.31 % 3,742 $ 36,394 (1) Represents an advance received from the lender on a multiple draw term loan in which the Company is making interest only payments through December 30, 2022 based on a 2.28% Secured Overnight Financing Rate plus a 2.75% spread.
Schedule of Debt Deferred Financing Costs And Discounts	Deferred financing fees and discounts related to the Company’s long-term debt were included as a contra liability to debt on the Consolidated Balance Sheets as follows: September 30, September 30, Current portion of deferred financing fees and discounts (1) $ (1,899) $ (1,866) Long-term portion of deferred financing fees and discounts (2) (7,974) (9,872) Total deferred financing fees and discounts $ (9,873) $ (11,738) (1) Included in Current portion of debt, net of deferred financing fees and discounts on the Consolidated Balance Sheets. (2) Included in Long-term debt, net of deferred financing fees and discounts on the Consolidated Balance Sheets.
Schedule of Aggregate Maturities of Long-term Debt	Aggregate maturities of all long‑term debt, including current portion of long‑term debt and excluding finance lease obligations as of September 30, 2022, are presented below: Fiscal Year 2023 $ 19,085 2024 167,870 2025 19,458 2026 173,775 2027 21,031 Thereafter 489,454 Total $ 890,673

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	12 Months Ended
	Sep. 30, 2022
Derivative [Line Items]
Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]	Year Ended September 30, 2022 2021 2020 Interest rate swap $ 36,550 $ 5,252 $ (5,155) Foreign currency forward contracts (583) (324) (201) Commodity swaps 8 (19) — Interest rate cap — — (19) $ 35,975 $ 4,909 $ (5,375)
Derivative Instruments, Gain (Loss) [Table Text Block]	The following represents the amount of (loss) gain reclassified from AOCI into earnings during the periods presented: Year Ended September 30, Location of (Loss) Gain 2022 2021 2020 Cost of product sales and services $ (136) $ (70) $ (8) General and administrative expense (229) (4) (192) Selling and marketing expense — (69) 28 Interest expense 1,152 (2,241) (486) $ 787 $ (2,384) $ (658)
Designated as Hedging Instrument
Derivative [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]	Asset Derivatives Balance Sheet Location September 30, 2022 September 30, 2021 Interest rate swaps Prepaid and other current assets $ 19,186 $ 3,127 Foreign currency forward contracts Prepaid and other current assets 467 6 Interest rate swaps Other non‑current assets 30,766 — Liability Derivatives Balance Sheet Location September 30, 2022 September 30, 2021 Foreign currency forward contracts Accrued expenses and other current liabilities $ 872 $ 102 Commodity swaps Accrued expenses and other current liabilities 7 19 Interest rate swaps Accrued expenses and other current liabilities — 303
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]	The following represents the fair value recorded for derivatives not designated as hedges for the periods presented: Asset Derivatives Balance Sheet Location September 30, September 30, Foreign currency forward contracts Prepaid and other current assets $ 40 $ 18 Liability Derivatives Balance Sheet Location September 30, September 30, Total return swaps—deferred compensation Accrued expenses and other current liabilities $ 632 $ 130
Derivative Instruments, Gain (Loss) [Table Text Block]	The following represents the amount of loss recognized in earnings for derivatives not designated as hedges during the periods presented: Year Ended September 30, Location of Loss 2022 2021 2020 General and administrative expense $ (1,130) $ (106) $ — $ (1,130) $ (106) $ —

Product Warranties (Tables)

Product Warranties (Tables)	12 Months Ended
	Sep. 30, 2022
Guarantees and Product Warranties [Abstract]
Schedule of product warranty liability	A reconciliation of the activity related to the accrued warranty, including both the current and long‑term portions, is as follows: Current Product Warranties Non-Current Product Warranties Year Ended September 30, Year Ended September 30, 2022 2021 2020 2022 2021 2020 Balance at beginning of the period $ 8,138 $ 6,115 $ 4,922 $ 2,966 $ 1,724 $ 2,332 Warranty provision for sales 6,732 6,939 4,738 2,835 2,065 701 Settlement of warranty claims (7,206) (4,720) (4,890) (2,022) (830) (1,170) Foreign currency translation and other (924) (196) 550 (314) 7 (274) Amounts related to sale of the Memcor product line — — 795 — — 135 Balance at end of the period $ 6,740 $ 8,138 $ 6,115 $ 3,465 $ 2,966 $ 1,724

Restructuring and Related Cha_2

Restructuring and Related Charges (Tables)	12 Months Ended
	Sep. 30, 2022
Restructuring and Related Activities [Abstract]
Schedule of restructuring components	The table below sets forth the amounts accrued for the restructuring components and related activity: Year Ended September 30, 2022 2021 2020 Balance at beginning of the period $ 304 $ 970 $ 655 Restructuring charges following the sale of the Memcor product line 979 5,588 8,274 Restructuring charges related to two-segment realignment 390 1,060 2,092 Restructuring charges related to other initiatives 4,517 2,830 1,867 Release of prior reserves (300) (329) (98) Write-off charges — (1,340) (2,461) Cash payments (5,222) (8,484) (9,367) Other adjustments (10) 9 8 Balance at end of the period $ 658 $ 304 $ 970 The table below sets forth the location of amounts recorded above on the Consolidated Statements of Operations: Year Ended September 30, 2022 2021 2020 Cost of product sales and services $ 2,217 $ 4,554 $ 8,305 General and administrative expense 2,574 3,199 3,053 Sales and marketing expense 83 348 305 Research and development expense 1 (16) 23 Other operating expense, net 711 1,064 449 $ 5,586 $ 9,149 $ 12,135

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Sep. 30, 2022
Retirement Benefits [Abstract]
Defined Benefit Plan, Plan with Projected Benefit Obligation in Excess of Plan Assets [Table Text Block]	The changes in projected benefit obligations, plan assets and the funded status of the UK and German defined benefit plans as of and for the years ended September 30, 2022 and 2021, respectively, are as follows: 2022 2021 Change in projected benefit obligation Projected benefit obligation at prior year measurement date $ 46,013 $ 47,389 Service cost 752 1,156 Interest cost 551 482 Actuarial gains (13,069) (2,312) Benefits paid from company assets (428) (738) Foreign currency exchange impact (7,165) 36 Projected benefit obligation at measurement date $ 26,654 $ 46,013 Change in plan assets Fair value of assets at prior year measurement date 28,638 27,530 Actual return on plan assets (4,639) 971 Benefits paid (109) (515) Employer contribution — 258 Foreign currency exchange impact (4,600) 394 Fair value of assets at measurement date $ 19,290 $ 28,638 Funded status and amount recognized in assets and liabilities $ (7,364) $ (17,375) Amount recognized in assets and liabilities Other non‑current assets $ 1,779 $ 2,960 Other non‑current liabilities $ (9,143) $ (20,335) Amount recognized in accumulated other comprehensive loss, before taxes Actuarial (gain) loss $ (1,067) $ 7,071
Schedule of Changes in Projected Benefit Obligations [Table Text Block]	The following table provides summary information for the UK and German plans where the projected benefit obligation is in excess of plan assets: September 30, 2022 September 30, 2021 Projected benefit obligation $ 26,654 $ 46,013 Accumulated benefit obligation $ 14,621 $ 24,578 Fair value of plan assets $ 19,290 $ 28,638
Defined Benefit Plan, Assumptions [Table Text Block]	2022 2021 Discount rate 2.03% - 4.97% 1.00% - 2.03% Expected long‑term rate of return on plan assets 2.82% - 5.74% 1.97% - 3.50% Salary scale 2.25% - 4.54% 2.25% - 4.36% Pension increases 1.00% - 3.42% 1.00% - 3.27%
Schedule of Allocation of Plan Assets [Table Text Block]	The actual overall asset allocation for the UK pension plan as compared to the investment policy goals as of September 30, 2022 was as follows by asset category: 2022 Actual 2022 Target Equity 26.7 % — % Index‑linked gilts 72.8 % 70 % Cash 0.5 % 30 %
Schedule of net benefit costs	Pension expense for the German and UK plans were as follows: Year Ended September 30, 2022 2021 2020 Service cost $ 752 $ 1,156 $ 1,125 Interest cost 551 482 492 Expected return on plan assets (771) (615) (387) Amortization of actuarial losses 584 1,042 1,006 Pension expense for defined benefit plans $ 1,116 $ 2,065 $ 2,236
Schedule of Expected Benefit Payments [Table Text Block]	Benefits expected to be paid to participants of the plans are as follows: Year Ended September 30, 2023 $ 880 2024 561 2025 648 2026 898 2027 828 Five years thereafter 7,616 Total $ 11,432

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	For financial reporting purposes, income (loss) before income taxes includes the following components: Year Ended September 30, 2022 2021 2020 Domestic $ 23,245 $ 19,927 $ 81,276 Foreign 46,068 41,815 40,490 Income before income taxes $ 69,313 $ 61,742 $ 121,766
Schedule of Components of Income Tax Expense (Benefit)	The components of income tax (expense) benefit were as follows: Year Ended September 30, 2022 2021 2020 Current: Federal $ — $ — $ — State (932) (1,233) (591) Foreign (11,056) (11,210) (8,014) $ (11,988) $ (12,443) $ (8,605) Deferred: Federal 9,470 (2,153) 115 State 6,168 (630) 401 Foreign (620) 5,146 718 $ 15,018 $ 2,363 $ 1,234 Total income tax (expense) benefit $ 3,030 $ (10,080) $ (7,371)
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of income tax (expense) benefit and the amount computed by applying the applicable statutory rate to income from operations before income taxes was as follows: Year Ended September 30, 2022 2021 2020 Income tax (expense) benefit at the federal statutory rate of 21% $ (14,556) $ (12,966) $ (25,571) State and local income taxes, net of federal tax benefit 989 (757) (74) Foreign tax rate differential (1,897) (3,009) (1,129) Nondeductible interest expense (578) (588) (1,032) Meals and entertainment expense (36) (176) (760) U.S. tax on foreign earnings (2,683) (5,687) (8,438) Other nondeductible expenses (2,952) (786) (479) Impact of tax rate changes (24) 819 286 Valuation allowances 17,087 854 19,013 Share-based compensation 6,990 11,598 4,931 Non-taxable gain on sale of subsidiary — — 4,789 Return-to-provision adjustments 1,790 (44) 516 Non-controlling interest 31 30 (466) Net benefit of foreign R&D expenses — — 18 Transaction related contingent liabilities 824 155 143 Deferred tax adjustments (2,317) 87 491 Accrued tax adjustments (138) 27 (6) Other 500 363 397 Total $ 3,030 $ (10,080) $ (7,371)
Schedule of Deferred Tax Assets and Liabilities	Significant components of deferred tax assets and liabilities were as follows: September 30, 2022 September 30, 2021 Deferred Tax Assets Receivable allowances $ 1,619 $ 885 Reserves and accruals 23,706 24,913 Inventory valuation and other assets 4,196 3,141 Investment in partnership — 1,977 Unrealized foreign exchange gains (losses), including related hedges 8,573 4,468 Right of use liabilities 12,021 — Other deferred tax assets 1,052 2,811 Net operating loss carryforwards 40,124 48,605 Gross deferred tax assets $ 91,291 $ 86,800 Less: Valuation allowance (3,740) (21,299) Deferred tax assets less valuation allowance $ 87,551 $ 65,501 Deferred Tax Liabilities Goodwill (8,162) (9,849) Fixed assets (48,992) (46,057) Intangibles (15,359) (15,313) Deferred tax liabilities in other comprehensive income (12,360) — Right of use assets (11,291) — Other deferred tax liabilities (1,751) (2,440) Gross deferred tax liabilities $ (97,915) $ (73,659) Net deferred tax liabilities $ (10,364) $ (8,158)
Summary of Valuation Allowance	A reconciliation of the valuation allowance on deferred tax assets is as follows: Year Ended September 30, 2022 2021 2020 Valuation allowance beginning of period $ 21,299 $ 23,298 $ 41,084 Change in assessment (17,305) (6,140) 1,650 Current year operations 217 7,300 (19,856) Foreign currency and other (471) (3,219) 3,012 Acquisitions / Dispositions — 60 (2,592) Valuation allowance end of period $ 3,740 $ 21,299 $ 23,298
Schedule of Unrecognized Tax Benefits Roll Forward	The following is a reconciliation of the Company’s total gross unrecognized tax benefits: Year Ended September 30, 2022 2021 2020 Balance as of beginning of period $ 1,123 $ 1,050 $ 1,075 Tax positions related to the current year Additions — — — Tax positions related to prior years Additions — 73 — Reductions (88) — (25) Expiration of statutes of limitations — — — Balance as of end of period $ 1,035 $ 1,123 $ 1,050
Summary of Operating Loss Carryforwards	Tax attributes available to reduce future taxable income begin to expire as follows: September 30, 2022 Begin Expiring Federal net operating loss $ 156,887 September 30, 2035 State net operating loss 78,348 September 30, 2023 State tax credits 43 September 30, 2036 Foreign net operating loss 2,121 September 30, 2023 Foreign net operating loss 8,644 Indefinite
Summary of Income Tax Open Years by Major Jurisdiction	The following table summarizes the Company’s open years by major jurisdiction as of September 30, 2022: Jurisdiction Open Tax Years United States 2019-2022 Australia 2018-2022 Canada 2018-2022 China 2017-2022 Germany 2018-2022 Netherlands 2017-2022 Singapore 2018-2022 United Kingdom 2020-2022

Share Based Compensation (Table

Share Based Compensation (Tables)	12 Months Ended
	Sep. 30, 2022
Share-Based Payment Arrangement [Abstract]
Stock options, activity	A summary of the stock option activity, including stock appreciation rights, for the years ended September 30, 2022 and 2021 is presented below: (In thousands, except per share amounts) Options Weighted Average Exercise Price/Share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding at September 30, 2020 7,430 $ 10.30 5.9 years $ 83,152 Granted 612 $ 24.78 Exercised (2,884) $ 6.81 Forfeited (67) $ 21.25 Cancelled (1) $ 16.63 Outstanding at September 30, 2021 5,090 $ 13.87 5.9 years $ 120,611 Granted 2 $ 46.75 Exercised (789) $ 8.86 Forfeited (38) $ 21.05 Outstanding at September 30, 2022 4,265 $ 14.74 5.2 years $ 78,218 Options exercisable at September 30, 2022 3,223 $ 12.51 4.4 years $ 66,272 Options vested and expected to vest at September 30, 2022 4,253 $ 14.72 5.2 years $ 78,093
Schedule of Nonvested Share Activity	A summary of the status of the Company's nonvested stock options, including stock appreciation rights, as of and for the years ended September 30, 2022, 2021 and 2020 is presented below. 2022 2021 2020 (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Shares Weighted Average Grant Date Fair Value/Share Shares Weighted Average Grant Date Fair Value/Share Unvested at beginning of period 1,901 $ 6.69 2,166 $ 5.56 2,379 $ 4.96 Granted 2 $ 24.22 612 $ 9.00 823 $ 6.06 Vested (823) $ 6.54 (810) $ 5.48 (864) $ 4.52 Forfeited (38) $ 6.87 (67) $ 6.82 (172) $ 4.94 Unvested at end of period 1,042 $ 6.82 1,901 $ 6.69 2,166 $ 5.56
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	The following is a summary of the RSU activity for the years ended September 30, 2022 and 2021. Shares Weighted Average Grant Date Fair Value/Share Outstanding at September 30, 2020 750 $ 17.86 Granted 731 $ 25.98 Vested (240) $ 17.55 Forfeited (25) $ 20.31 Cancelled (7) $ 21.22 Outstanding at September 30, 2021 1,209 $ 22.77 Granted 328 $ 44.88 Vested (507) $ 22.23 Forfeited (50) $ 27.96 Outstanding at September 30, 2022 980 $ 30.18 Expected to vest at September 30, 2022 959 $ 30.05 Performance Share Units The following is a summary of the PSU activity for the years ended September 30, 2022 and 2021. (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Unvested at September 30, 2020 — $ — Granted 469 $ 16.92 Nonvested at September 30, 2021 469 $ 16.92 Granted 124 $ 52.50 Forfeited (1) $ 47.92 Nonvested at September 30, 2022 592 $ 23.36 Expected to vest at September 30, 2022 555 $ 23.25
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]	Reported non-cash share-based compensation expense was classified on the Consolidated Statements of Operations as shown in the following table: Year Ended September 30, 2022 2021 2020 Cost of services $ 234 $ 143 $ 91 General and administrative 21,870 15,381 10,418 $ 22,104 $ 15,524 $ 10,509
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	Valuation assumptions for options and stock appreciation rights granted are as follows for the years ended September 2022, 2021 and 2020, respectively: Year Ended September 30, 2022 2021 2020 Expected volatility 55.3% 38.3% - 56.7% 24.2% - 77.1% Expected dividends — — — Expected term (in years) 5.9 5.3 - 6.0 5.4 - 6.0 Risk free rate 1.4% 0.4% - 0.9% 0.2% - 1.7% Grant date fair value per share of options and stock appreciation rights granted $24.22 $8.12 - $19.76 $5.33 - $8.56

Other Comprehensive Loss (Table

Other Comprehensive Loss (Tables)	12 Months Ended
	Sep. 30, 2022
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The components of accumulated other comprehensive income (loss) were: September 30, 2022 September 30, 2021 Foreign currency translation income $ 6,767 $ 16,137 Pension benefit plans, net of tax expense of $2,790 and $403 (1,776) (7,474) Unrealized derivative gain on cash flow hedges, net of tax expense of $11,770 and $135 37,940 2,752 Total accumulated other comprehensive income $ 42,931 $ 11,415 The (losses) gains in accumulated other comprehensive income (loss) by component, net of tax, for the years ended September 30, 2022, 2021 and 2020 are as follows: Foreign currency Pension Cash flow Hedges Balance at September 30, 2019 $ (2,705) $ (10,475) $ 176 Other comprehensive loss before reclassifications (2,830) (927) (5,375) Amounts gains reclassified from accumulated other comprehensive loss into earnings — 1,006 658 Balance at September 30, 2020 $ (5,535) $ (10,396) $ (4,541) Other comprehensive income before reclassifications 21,672 1,880 4,909 Amounts gains reclassified from accumulated other comprehensive loss into earnings — 1,042 2,384 Balance at September 30, 2021 $ 16,137 $ (7,474) $ 2,752 Other comprehensive (loss) income before reclassifications (9,370) 5,114 35,975 Amounts gains (losses) reclassified from accumulated other comprehensive loss (income) into earnings — 584 (787) Balance at September 30, 2022 $ 6,767 $ (1,776) $ 37,940

Concentration of Credit Risk (T

Concentration of Credit Risk (Tables)	12 Months Ended
	Sep. 30, 2022
Risks and Uncertainties [Abstract]
Schedule of Revenue from External Customers by Geographic Areas	Information regarding revenue disaggregated by geographic area is as follows: Year Ended September 30, 2022 2021 2020 United States $ 1,431,095 $ 1,174,474 $ 1,164,634 Asia 129,981 113,316 77,253 Europe 108,271 113,559 108,139 Canada 54,935 49,952 65,223 Australia 12,794 13,128 14,207 Total $ 1,737,076 $ 1,464,429 $ 1,429,456 The following tables set forth external net revenue, net of intercompany eliminations, and net asset information by region: Year Ended September 30, 2022 2021 2020 Sales to external customers United States $ 1,431,095 $ 1,174,474 $ 1,164,634 Rest of World 305,981 289,955 264,822 Total $ 1,737,076 $ 1,464,429 $ 1,429,456
Schedule of Long-lived Assets by Geographic Areas	September 30, 2022 September 30, 2021 Net Assets United States $ 558,512 $ 462,883 Rest of World 151,581 119,336 $ 710,093 $ 582,219 Long Lived Assets United States $ 388,591 $ 357,597 Rest of World 16,698 17,391 $ 405,289 $ 374,988

Leases (Tables)

Leases (Tables)	12 Months Ended
	Sep. 30, 2022
Leases [Abstract]
Lease, Cost	The following represents the components of lease cost for the years ended September 30, 2022, 2021, and 2020 and other information for both operating and finance leases for the years ended September 30, 2022, 2021, and 2020: Year Ended September 30, 2022 2021 2020 Lease cost Finance lease cost: Amortization of ROU assets $ 13,461 $ 13,572 $ 13,738 Interest on lease liabilities 1,574 1,793 1,981 Operating lease cost 16,529 15,357 16,052 Short-term lease cost 875 2,935 4,970 Sublease income — (58) (56) Total lease cost $ 32,439 $ 33,599 $ 36,685
Schedule of Other Lease Information	Year Ended September 30, Other information 2022 2021 2020 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from finance leases $ 1,573 $ 1,810 $ 1,968 Operating cash flows from operating leases $ 17,178 $ 15,758 $ 16,034 Financing cash flows from finance leases $ 13,356 $ 13,373 $ 13,459 ROU assets obtained in exchange for new finance lease liabilities $ 15,329 $ 14,257 $ 14,934 ROU assets obtained in exchange for new operating lease liabilities $ 14,151 $ 4,839 $ 8,456 ROU asset remeasurement $ 6,723 $ 8,177 $ (960) Weighted average remaining lease term - finance leases 3.5 years 3.6 years 3.9 years Weighted average remaining lease term - operating leases 4.6 years 4.8 years 5.2 years Weighted average discount rate - finance leases 4.2 % 4.3 % 4.6 % Weighted average discount rate - operating leases 4.2 % 4.0 % 4.2 %
Lessee, Operating Lease, Liability, Maturity	The following table reconciles future minimum undiscounted rental commitments for operating leases to operating lease liabilities record on the Consolidated Balance Sheet as of September 30, 2022: Fiscal Year 2023 $ 16,995 2024 14,927 2025 12,585 2026 9,345 2027 5,815 Thereafter 4,788 Total undiscounted lease payments $ 64,455 Present value adjustment (5,562) Operating lease liabilities $ 58,893 Less current installments of obligations under operating leases 14,932 Obligations under operating leases, excluding current installments $ 43,961
Schedule Of Finance Lease, Right-of-Use Asset	The gross and net carrying values of the equipment under finance leases as of September 30, 2022 and September 30, 2021 was as follows: September 30, 2022 September 30, 2021 Gross carrying amount $ 85,217 $ 92,247 Net carrying amount $ 37,715 $ 36,884
Finance Lease, Liability, Fiscal Year Maturity	The following table reconciles future minimum undiscounted rental commitments for finance leases to the finance lease liabilities recorded on the Consolidated Balance Sheet as of September 30, 2022: Fiscal Year 2023 $ 14,220 2024 11,669 2025 8,674 2026 5,132 2027 1,938 Thereafter 209 Total undiscounted lease payments $ 41,842 Present value adjustment (2,779) Finance lease liabilities $ 39,063 Less current installments of obligations under finance leases 12,875 Obligations under finance leases, excluding current installments $ 26,188
Schedule of Components of Lease Revenue	The following represents the components of lease revenue for the years ended September 30, 2022, 2021, and 2020: Year Ended September 30, 2022 2021 2020 Lease revenue: operating leases $ 164,574 $ 152,435 $ 148,703 Lease revenue: sales-type leases 16,937 37,898 981 Total lease revenue $ 181,511 $ 190,333 $ 149,684
Lessor, Operating Lease, Payment to be Received, Fiscal Year Maturity	As of September 30, 2022, future minimum lease payments receivable under operating leases are as follows: Fiscal year 2023 $ 165,025 2024 99,403 2025 69,620 2026 46,650 2027 34,700 Thereafter 181,314 Future minimum lease payments $ 596,712
Sales-type Lease Receivable, Maturity	As of September 30, 2022, the maturities of the Company’s sales type lease receivables are as follows: Fiscal year 2023 $ 3,001 2024 4,128 2025 4,128 2026 4,128 2027 4,128 Thereafter 34,970 Total $ 54,483

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Schedule of Credit Facilities	The following table summarizes the amount of the Company’s outstanding borrowings and outstanding letters of credit under the 2021 Revolving Credit Facility as of September 30, 2022, and September 30, 2021. September 30, September 30, Borrowing availability $ 350,000 $ 350,000 Outstanding borrowings 151,000 37,000 Outstanding letters of credit 9,317 10,112 Unused amounts $ 189,683 $ 302,888 The following summarizes the Company’s outstanding letters of credit and surety bonds as of September 30, 2022 and September 30, 2021, respectively. September 30, 2022 September 30, 2021 Revolving credit capacity $ 60,000 $ 60,000 Letters of credit outstanding 9,317 10,112 Remaining revolving credit capacity $ 50,683 $ 49,888 Surety capacity $ 261,959 $ 250,000 Surety issuances 134,037 147,845 Remaining surety available $ 127,922 $ 102,155

Accrued Expenses and Other Li_2

Accrued Expenses and Other Liabilities (Tables)	12 Months Ended
	Sep. 30, 2022
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses and other liabilities consisted of the following: September 30, September 30, Salaries, wages, and other benefits $ 83,618 $ 79,110 Obligation under operating leases 14,932 13,316 Obligation under finance leases 12,875 12,093 Third party commissions 10,341 10,031 Deferred revenue 9,692 5,241 Taxes, other than income 5,594 4,575 Insurance liabilities 3,456 3,720 Provisions for litigation 2,375 2,938 Fair value of liability derivatives 1,511 554 Severance payments 658 304 Earn-outs related to acquisitions — 150 Other 33,220 28,335 $ 178,272 $ 160,367

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Sep. 30, 2022
Segment Reporting [Abstract]
Schedule of segment reporting information, by segment	Year Ended September 30, 2022 2021 2020 Total sales Integrated Solutions and Services $ 1,222,165 $ 980,852 $ 954,542 Applied Product Technologies 653,245 588,080 559,635 Total sales $ 1,875,410 $ 1,568,932 $ 1,514,177 Intersegment sales Integrated Solutions and Services $ 37,688 $ 20,966 $ 10,360 Applied Product Technologies 100,646 83,537 74,361 Total intersegment sales $ 138,334 $ 104,503 $ 84,721 Sales to external customers Integrated Solutions and Services $ 1,184,477 $ 959,886 $ 944,182 Applied Product Technologies 552,599 504,543 485,274 Total sales $ 1,737,076 $ 1,464,429 $ 1,429,456 Income from operations Integrated Solutions and Services $ 165,562 $ 147,251 $ 145,655 Applied Product Technologies 103,087 82,891 134,258 Corporate (164,656) (130,825) (111,465) Total income from operations $ 103,993 $ 99,317 $ 168,448 Interest expense (34,680) (37,575) (46,682) Income before income taxes $ 69,313 $ 61,742 $ 121,766 Income tax benefit (expense) 3,030 (10,080) (7,371) Net income $ 72,343 $ 51,662 $ 114,395 Depreciation and amortization Integrated Solutions and Services $ 83,866 $ 70,585 $ 67,489 Applied Product Technologies 13,918 14,423 14,226 Corporate 29,786 28,656 25,553 Total depreciation and amortization $ 127,570 $ 113,664 $ 107,268 Capital expenditures Integrated Solutions and Services $ 66,897 $ 60,407 $ 75,551 Applied Product Technologies 6,704 6,955 6,237 Corporate 8,444 7,931 6,668 Total Capital expenditures $ 82,045 $ 75,293 $ 88,456 September 30, 2022 September 30, 2021 Assets Integrated Solutions and Services $ 1,123,166 $ 887,265 Applied Product Technologies 653,244 656,362 Corporate 414,453 325,264 Total assets $ 2,190,863 $ 1,868,891 Goodwill Integrated Solutions and Services $ 306,935 $ 233,830 Applied Product Technologies 166,637 173,546 Total goodwill $ 473,572 $ 407,376

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Sep. 30, 2022
Earnings Per Share [Abstract]
Schedule of earnings per share, basic and diluted	The following table sets forth the computation of basic and diluted income from continuing operations per common share: Year Ended September 30, (In thousands, except per share data) 2022 2021 2020 Numerator: Net income attributable to Evoqua Water Technologies Corp. $ 72,198 $ 51,482 $ 113,649 Denominator: Denominator for basic net income per common share—weighted average shares 121,138 119,575 116,721 Effect of dilutive securities: Share‑based compensation 3,744 3,368 4,342 Denominator for diluted net loss per common share—adjusted weighted average shares 124,882 122,943 121,063 Basic income per common share $ 0.60 $ 0.43 $ 0.97 Diluted income per common share $ 0.58 $ 0.42 $ 0.94

SCHEDULE_I - Evoqua Water Tec_2

SCHEDULE I - Evoqua Water Technologies Corp. (Tables)	12 Months Ended
	Sep. 30, 2022
Condensed Financial Information Disclosure [Abstract]
Condensed Balance Sheet	Condensed Consolidated Balance Sheets (In thousands) September 30, 2022 September 30, 2021 ASSETS Current assets $ 67,403 $ 51,777 Due from affiliates 62,080 39,982 Cash and cash equivalents 5,202 11,681 Prepaid and other current assets 121 114 Investment in affiliate 600,064 517,479 Total assets $ 667,467 $ 569,256 LIABILITIES AND EQUITY Other current liabilities 305 — Total liabilities $ 305 $ — Common stock, par value $0.01: authorized 1,000,000 shares; issued 123,411 shares, outstanding 121,747 at September 30, 2022; issued 122,173 shares, outstanding 120,509 at September 30, 2021 1,235 1,223 Treasury stock: 1,664 shares at September 30, 2022 and 1,664 shares at September 30, 2021 (2,837) (2,837) Additional paid‑in capital 607,748 582,052 Retained earnings (deficit) 61,016 (11,182) Total shareholders’ equity $ 667,162 $ 569,256 Total liabilities and shareholder’s equity $ 667,467 $ 569,256
Condensed Income Statement	Condensed Statements of Operations (In thousands) Year Ended September 30, 2022 2021 2020 Other operating income (expense) $ 8 $ (1,073) $ 16 General and administrative expense (454) (426) (476) Net income of subsidiaries 72,644 52,981 114,109 Income before taxes 72,198 51,482 113,649 Benefit for income taxes — — — Net income $ 72,198 $ 51,482 $ 113,649
Condensed Cash Flow Statement	Condensed Statements of Cash Flows (Parent company only) (In thousands) Year Ended September 30, 2022 2021 2020 Operating activities Net income $ 72,198 $ 51,482 $ 113,649 Adjustments to reconcile net income (loss) to net cash used in operating activities Net income of subsidiaries (72,644) (52,981) (114,109) Foreign currency exchange gains on intercompany loans — — (15) Changes in assets and liabilities Due from affiliates (9,606) (11,638) 5,842 Due to affiliates — — (9,747) Accrued expenses 305 — 160 Prepaids and other current assets (7) (36) (24) Net cash used in operating activities $ (9,754) $ (13,173) $ (4,244) Investing activities Contributed capital $ — $ — $ — Net cash used in investing activities $ — $ — $ — Financing activities Proceeds from issuance of common stock $ 9,556 $ 21,205 $ 18,927 Taxes paid related to net share settlements of share-based compensation awards (6,281) (1,323) (9,832) Net cash provided by financing activities $ 3,275 $ 19,882 $ 9,095 Change in cash and cash equivalents $ (6,479) $ 6,709 $ 4,851 Cash and cash equivalents Beginning of period 11,681 4,972 121 End of period $ 5,202 $ 11,681 $ 4,972

Description of the Company an_2

Description of the Company and Basis of Presentation (Details) - segment		12 Months Ended
	Oct. 29, 2018	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments	3	2

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Sales to external customers		$ 1,737,076	$ 1,464,429	$ 1,429,456
Foreign currency losses (gains) on intracompany loans		$ 18,712	$ (927)	$ (8,216)
Minimum | Transferred at Point in Time
Finite-Lived Intangible Assets [Line Items]
Sales to external customers	$ 100
Machinery and equipment | Minimum
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life		3 years
Machinery and equipment | Maximum
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life		20 years
Building and Building Improvements | Minimum
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life		10 years
Building and Building Improvements | Maximum
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life		40 years

Variable Interest Entities (Nar

Variable Interest Entities (Narrative) (Details)	12 Months Ended
	Sep. 30, 2022	Apr. 01, 2022	Apr. 30, 2021	Feb. 28, 2021	Oct. 01, 2019
Variable Interest Entity [Line Items]
Variable interest entity, obligation to absorb risk, percentage of equity	100%
Frontier
Variable Interest Entity [Line Items]
Business acquisition, percentage of voting interests acquired		32%	8%		60%
Frontier | Minority Owners
Variable Interest Entity [Line Items]
Ownership interest remaining				10%	40%
Treated Water Outsourcing
Variable Interest Entity [Line Items]
Variable interest entity, ownership percentage	50%

Variable Interest Entities (Sum

Variable Interest Entities (Summarized Financial Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Variable Interest Entity [Line Items]
Current assets	$ 831,389	$ 678,458
Property, plant, and equipment, net	405,289	374,988
Goodwill	473,572	407,376	$ 397,205
Intangible assets, net	317,733	290,075
Liabilities	1,480,770	1,286,672
Revenue	1,737,076	1,464,429	1,429,456
Total operating expenses	(437,295)	(363,010)	(341,962)
Income from operations	103,993	99,317	168,448
Treated Water Outsourcing
Variable Interest Entity [Line Items]
Cash		1,380
Current assets		3,202
Property, plant, and equipment, net		903
Goodwill		2,206
Liabilities		1,009
Revenue	1,641	3,315	5,944
Total operating expenses	(1,440)	(2,922)	(4,519)
Income from operations	201	393	1,425
Frontier
Variable Interest Entity [Line Items]
Cash		2,095
Current assets		12,495
Property, plant, and equipment, net		2,113
Goodwill		1,798
Intangible assets, net		8,265
Liabilities		9,425
Revenue	13,363	14,340	5,365
Total operating expenses	(12,135)	(14,362)	(8,219)
Income from operations	$ 1,228	$ (22)	$ (2,854)

Acquisitions and Divestitures_2

Acquisitions and Divestitures (Epicor) (Details) - USD ($) $ in Thousands		12 Months Ended
	Jul. 15, 2022	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Cash paid to acquire business		$ 229,277	$ 21,037	$ 13,108
Epicor Inc
Business Acquisition [Line Items]
Cash paid to acquire business	$ 4,339
Acquisition costs		$ 172
Current assets	40
Property, plant, and equipment	116
Identifiable assets, net	4,281
Other non-current assets	472
Total assets acquired	4,909
Current liabilities	(456)
Non-current liabilities	(114)
Total liabilities assumed	(570)
Net assets acquired	$ 4,339

Acquisitions and Divestitures_3

Acquisitions and Divestitures (Smith Engineering) (Details) $ in Thousands		12 Months Ended
	Jul. 01, 2022 USD ($) numberOfCustomers	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Business Acquisition [Line Items]
Cash paid to acquire business		$ 229,277	$ 21,037	$ 13,108
Goodwill		473,572	$ 407,376	$ 397,205
Smith Engineering Inc
Business Acquisition [Line Items]
Cash paid to acquire business	$ 18,878
Escrow deposit	$ 2,895
Number of customers | numberOfCustomers	1,200
Acquisition costs		$ 421
Receivables, net	$ 2,501
Inventories, net	1,345
Other current assets	937
Property, plant, and equipment	532
Goodwill	7,820
Identifiable assets, net	9,815
Other non-current assets	796
Assets acquired	23,746
Current liabilities	(1,834)
Non-current liabilities	(3,034)
Liabilities assumed	(4,868)
Net assets acquired	$ 18,878

Acquisitions and Divestitures_4

Acquisitions and Divestitures (Narrative) (Details) - USD ($) $ in Thousands				12 Months Ended
	Apr. 01, 2022	Jan. 03, 2022	Dec. 20, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Apr. 30, 2021	Oct. 31, 2019	Oct. 01, 2019
Business Acquisition [Line Items]
Borrowings under credit facility				$ 0	$ 0	$ 2,597
Acquired finite-lived intangible assets, weighted average useful life				6 years
Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired		$ 42,181
Trade Names and Developed Technology
Business Acquisition [Line Items]
Finite-lived intangible assets acquired		14,913
Frontier
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	32%						8%		60%
Payments to acquire businesses	$ 10,396
Consideration transferred, including amounts from prior periods	$ 22,771
Treated Water Outsourcing
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	50%
Payments to acquire businesses	$ 1,099
Mar Cor
Business Acquisition [Line Items]
Payments to acquire businesses		194,976
Price of acquisition, expected			$ 196,300
Borrowings under credit facility		160,000
Contingent consideration, liability			$ 12,300
Escrow deposit		12,965
Acquisition costs				$ 4,865
Identifiable assets, net		$ 57,094
Mar Cor | Customer Relationships | Minimum
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		3 years
Mar Cor | Customer Relationships | Maximum
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		9 years
Mar Cor | Trade Names
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		15 years
Mar Cor | Developed Technology
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		4 years
Mar Cor | Know-how Intangibles
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		9 years
Mar Cor | General Indemnity
Business Acquisition [Line Items]
Escrow deposit		$ 9,815
Mar Cor | Working Capital Adjustments
Business Acquisition [Line Items]
Escrow deposit		$ 3,150
Frontier
Business Acquisition [Line Items]
Ownership interest percentage acquired							8%	60%

Acquisitions and Divestitures -

Acquisitions and Divestitures - (Mar Cor Acquisition) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jan. 03, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Combination, Separately Recognized Transactions [Line Items]
Goodwill	$ 473,572		$ 407,376	$ 397,205
Mar Cor
Business Combination, Separately Recognized Transactions [Line Items]
Receivables, net		$ 21,275
Inventories, net		32,350
Earn-out assets related to acquisitions	$ 11,597	7,824	$ 0
Other current assets		1,844
Property, plant, and equipment		19,150
Goodwill		68,754
Identifiable assets, net		57,094
Other non-current assets		7,694
Total assets acquired		215,985
Current liabilities		(15,467)
Non-current liabilities		(5,542)
Total liabilities assumed		(21,009)
Net assets acquired		$ 194,976

Acquisitions and Divestitures_5

Acquisitions and Divestitures ( Divestitures) (Details) - USD ($) $ in Thousands		12 Months Ended
	Mar. 01, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture		$ 356	$ 897	$ 118,894
Gain (loss) on sale of business		193	(193)	$ 68,051
Germany Regan Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture		356
Gain (loss) on sale of business		$ 193
Lange Product Line
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture	$ 897
Gain (loss) on sale of business			$ (193)

Acquisitions and Divestitures_6

Acquisitions and Divestitures (WCSI Acquisition) (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 01, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Cash paid to acquire assets		$ 229,277	$ 21,037	$ 13,108
Goodwill		473,572	407,376	$ 397,205
Water consulting specialists, inc
Business Acquisition [Line Items]
Cash paid to acquire assets	$ 12,025
Contingent consideration, liability	761	150
Cash from previous acquisition		$ 21
Acquisition costs			$ 83
Current assets	1,813
Property, plant, and equipment	221
Goodwill	4,340
Identifiable assets, net	7,336
Other non-current assets	86
Total assets acquired	13,796
Liabilities assumed	(1,792)
Net assets acquired	$ 12,004

Acquisitions and Divestitures_7

Acquisitions and Divestitures (Ultrapure Acquisition) (Details) - USD ($) $ in Thousands			12 Months Ended
	Apr. 01, 2021	Dec. 17, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Cash paid to acquire assets			$ 229,277	$ 21,037	$ 13,108
Goodwill			$ 473,572	407,376	$ 397,205
Ultrapure
Business Acquisition [Line Items]
Cash paid to acquire assets		$ 8,743
Adjustment, consideration transferred	$ 290
Acquisition costs				$ 230
Current assets		2,366
Property, plant, and equipment		963
Goodwill		2,836
Identifiable assets, net		3,751
Other non-current assets		21
Total assets acquired		9,937
Liabilities assumed		(904)
Net assets acquired		$ 9,033

Revenue (Disaggregation of Reve

Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Sales to external customers	$ 1,737,076	$ 1,464,429	$ 1,429,456
Other	181,511	190,333	149,684
Transferred over Time
Disaggregation of Revenue [Line Items]
Sales to external customers	688,398	615,978	592,755
United States
Disaggregation of Revenue [Line Items]
Sales to external customers	1,431,095	1,174,474	1,164,634
Europe
Disaggregation of Revenue [Line Items]
Sales to external customers	108,271	113,559	108,139
Asia
Disaggregation of Revenue [Line Items]
Sales to external customers	129,981	113,316	77,253
CANADA
Disaggregation of Revenue [Line Items]
Sales to external customers	54,935	49,952	65,223
AUSTRALIA
Disaggregation of Revenue [Line Items]
Sales to external customers	12,794	13,128	14,207
Revenue from aftermarket
Disaggregation of Revenue [Line Items]
Sales to external customers	364,090	245,048	247,102
Revenue from service
Disaggregation of Revenue [Line Items]
Sales to external customers	684,588	603,403	589,599
Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Sales to external customers	1,184,477	959,886	944,182
Integrated Solutions and Services | Transferred over Time
Disaggregation of Revenue [Line Items]
Sales to external customers	304,925	250,187	257,528
Integrated Solutions and Services | Revenue from aftermarket
Disaggregation of Revenue [Line Items]
Sales to external customers	215,972	128,585	119,051
Integrated Solutions and Services | Revenue from service
Disaggregation of Revenue [Line Items]
Sales to external customers	663,580	581,114	567,603
Applied Product Technologies
Disaggregation of Revenue [Line Items]
Sales to external customers	552,599	504,543	485,274
Applied Product Technologies | Transferred over Time
Disaggregation of Revenue [Line Items]
Sales to external customers	383,473	365,791	335,227
Applied Product Technologies | Revenue from aftermarket
Disaggregation of Revenue [Line Items]
Sales to external customers	148,118	116,463	128,051
Applied Product Technologies | Revenue from service
Disaggregation of Revenue [Line Items]
Sales to external customers	21,008	22,289	21,996
Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Sales to external customers	$ 1,555,565	$ 1,274,096	$ 1,279,772

Revenue (Performance Obligation

Revenue (Performance Obligations) (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 377,091
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01 | Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01 | Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	24 months

Revenue (Contract Assets and Li

Revenue (Contract Assets and Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Contract assets	$ 102,123	$ 72,746	$ 80,759
Recognized in current period	401,825	316,864
Reclassified to accounts receivable	(368,936)	(325,405)
Foreign currency	(3,512)	528
Contract liabilities	62,439	55,883	$ 26,259
Recognized in current period	370,375	349,046
Amounts in beginning balance reclassified to revenue	(44,313)	(25,523)
Current period amounts reclassified to revenue	(319,513)	(294,033)
Foreign currency	$ 7	$ 134

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Jan. 03, 2022	Sep. 30, 2021	Sep. 30, 2020
Deferred compensation plan assets
Mutual Funds			$ 17,806
Liabilities:
Unrealized gain	$ (2,537)
Decrease in fair value of earn-out liability	$ 150
Frontier
Liabilities:
Percentage of voting interest remaining	32%
Liabilities, fair value adjustment	$ 2,091
Mar Cor
Deferred compensation plan assets
Earn-out assets related to acquisitions	11,597	$ 7,824	0
Liabilities:
Increase in the fair value of the Earn Out asset	3,773
Fair Value, Inputs, Level 1 | Fair Value, Recurring
Deferred compensation plan assets
Cash	902		1,251
Mutual Funds	12,330
Fair Value, Inputs, Level 1 | Cash | Fair Value, Recurring
Assets:
Fair value of plan assets	40		831
Fair Value, Inputs, Level 2 | Fair Value, Recurring
Assets:
Interest Rate Derivative Assets, at Fair Value	49,952		3,127
Deferred compensation plan assets
Foreign currency forward contracts	507		24
Liabilities:
Pension plan	(26,654)		(46,013)
Deferred compensation plan liabilities	(20,081)		(24,382)
Total return swaps—deferred compensation	(632)		(130)
Long‑term debt	(884,517)		(752,988)
Interest rate swaps			(303)
Foreign currency forward contracts	(872)		(102)
Fair Value, Inputs, Level 2 | Commodity Contract | Fair Value, Recurring
Liabilities:
Derivative Liability	(7)		(19)
Fair Value, Inputs, Level 3 | Fair Value, Recurring
Liabilities:
Earn-out liabilities related to acquisitions	0		(150)	$ (295)
Purchase Right	0		8,305
Fair Value, Inputs, Level 3 | Fair Value, Recurring | Other Current Liabilities
Liabilities:
Earn-out liabilities related to acquisitions	0		(150)	(295)
Fair Value, Inputs, Level 3 | Fair Value, Recurring | Other Noncurrent Liabilities
Liabilities:
Earn-out liabilities related to acquisitions	0		0	$ 0
Net Asset Value | Global Multi-Asset Fund | Fair Value, Recurring
Assets:
Plan assets at net asset value	11,632		15,244
Net Asset Value | Government Securities | Fair Value, Recurring
Assets:
Plan assets at net asset value	3,343		5,158
Net Asset Value | Liability Driven Investment | Fair Value, Recurring
Assets:
Plan assets at net asset value	928		2,793
Net Asset Value | Guernsey Unit Trust | Fair Value, Recurring
Assets:
Plan assets at net asset value	2,048		2,387
Net Asset Value | Global Absolute Return | Fair Value, Recurring
Assets:
Plan assets at net asset value	$ 1,299		$ 2,225

Fair Value Measurements (Rollfo

Fair Value Measurements (Rollforward of acquisition earnouts) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	General and Administrative Expense	General and Administrative Expense
Fair Value, Recurring | Fair Value, Inputs, Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	$ 150	$ 295
Acquisitions		761
Payments		(170)
Fair value adjustment	(150)	(736)
Balance at the end of the period	0	150
Other Current Liabilities | Fair Value, Recurring | Fair Value, Inputs, Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	150	295
Acquisitions		761
Payments		(170)
Fair value adjustment	(150)	(736)
Balance at the end of the period	0	150
Other Noncurrent Liabilities | Fair Value, Recurring | Fair Value, Inputs, Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	0	0
Acquisitions		0
Payments		0
Fair value adjustment	0	0
Balance at the end of the period	$ 0	$ 0

Accounts Receivable (Details)

Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Receivables [Abstract]
Accounts Receivable	$ 312,600	$ 282,819
Allowance for Credit Losses	(6,888)	(4,824)
Receivables, net	$ 305,712	$ 277,995

Accounts Receivable - Movement

Accounts Receivable - Movement in the allowance for credit losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ (4,824)	$ (4,057)	$ (4,906)
Charged to costs and expenses	(1,997)	(1,733)	(537)
Write-offs	473	780	1,277
Foreign currency and other	(540)	186	109
Balance at end of period	$ (6,888)	$ (4,824)	$ (4,057)

Inventories (Schedule of Major

Inventories (Schedule of Major Classes of Inventory) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 120,532	$ 86,469
Work in progress	36,499	19,842
Finished goods and products held for resale	80,811	59,624
Costs of unbilled projects	2,309	2,277
Reserves for excess and obsolete	(10,800)	(9,709)
Inventory, Net	$ 229,351	$ 158,503

Inventories (Activity in Reserv

Inventories (Activity in Reserves for Excess and Obsolete Inventory) (Details) - SEC Schedule, 12-09, Reserve, Inventory [Member] - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowance beginning of period	$ (9,709)	$ (11,467)	$ (13,370)
Change to reserve requirement	(2,608)	265	(310)
Write-offs	684	1,516	2,197
Foreign currency and other	833	(23)	16
Valuation allowance end of period	$ (10,800)	$ (9,709)	$ (11,467)

Property, Plant, and Equipmen_2

Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 823,848	$ 764,394
Less: accumulated depreciation	(418,559)	(389,406)
Property, plant and equipment, net	405,289	374,988
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	401,334	388,352
Rental equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	267,345	246,257
Land and buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	82,985	70,048
Construction in process
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 72,184	$ 59,737

Property, Plant, and Equipmen_3

Property, Plant, and Equipment (Secured Financings) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Debt Instrument [Line Items]
Property, plant and equipment, gross	$ 823,848	$ 764,394
Property, plant, and equipment, net	405,289	374,988
Collateral Pledged | Equipment Financings
Debt Instrument [Line Items]
Property, plant and equipment, gross	136,277	104,136
Property, plant, and equipment, net	112,442	87,540
Machinery and equipment
Debt Instrument [Line Items]
Property, plant and equipment, gross	401,334	388,352
Machinery and equipment | Collateral Pledged | Equipment Financings
Debt Instrument [Line Items]
Property, plant and equipment, gross	86,294	73,632
Property, plant, and equipment, net	62,459	57,036
Construction in process
Debt Instrument [Line Items]
Property, plant and equipment, gross	72,184	59,737
Construction in process | Collateral Pledged | Equipment Financings
Debt Instrument [Line Items]
Property, plant and equipment, gross	49,983	30,504
Property, plant, and equipment, net	$ 49,983	$ 30,504

Property, Plant, and Equipmen_4

Property, Plant, and Equipment (Depreciation and maintenance and repairs expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 82,637	$ 76,279	$ 73,002
Maintenance and repair expense	$ 30,425	$ 22,354	$ 20,303

Goodwill (Schedule) (Details)

Goodwill (Schedule) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Goodwill [Roll Forward]
Goodwill, beginning of the period	$ 407,376	$ 397,205
Business combinations and divestitures	76,156	10,349
Measurement period adjustments	379	(3,216)
Foreign currency translation	(10,339)	3,038
Goodwill, end of the period	473,572	407,376
Integrated Solutions and Services
Goodwill [Roll Forward]
Goodwill, beginning of the period		224,381
Business combinations and divestitures		10,349
Measurement period adjustments		(3,216)
Foreign currency translation		2,316
Applied Product Technologies
Goodwill [Roll Forward]
Goodwill, beginning of the period		172,824
Business combinations and divestitures		0
Measurement period adjustments		0
Foreign currency translation		722
Operating Segments [Member] | Integrated Solutions and Services
Goodwill [Roll Forward]
Goodwill, beginning of the period	233,830
Business combinations and divestitures	76,190
Measurement period adjustments	379
Foreign currency translation	(3,464)
Goodwill, end of the period	306,935	233,830
Operating Segments [Member] | Applied Product Technologies
Goodwill [Roll Forward]
Goodwill, beginning of the period	173,546
Business combinations and divestitures	(34)
Measurement period adjustments	0
Foreign currency translation	(6,875)
Goodwill, end of the period	$ 166,637	$ 173,546

Goodwill (Details)

Goodwill (Details) - USD ($)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill deductible for tax purposes	$ 250,636,000	$ 159,730,000
Goodwill, Impairment Loss	$ 0

Other Intangible Assets (Detail

Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Finite-Lived Intangible Assets [Line Items]
Carrying amount, finite-lived intangible assets	$ 586,303	$ 520,108
Accumulated Amortization	(302,777)	(264,240)
Total	283,526	255,868
Indefinite‑lived intangible assets	34,207	34,207
Carrying amount, intangible assets	620,510	554,315
Intangible assets, net	317,733	290,075
Customer related
Finite-Lived Intangible Assets [Line Items]
Carrying amount, finite-lived intangible assets	346,128	300,963
Accumulated Amortization	(122,604)	(101,272)
Total	223,524	199,691
Proprietary technology
Finite-Lived Intangible Assets [Line Items]
Carrying amount, finite-lived intangible assets	68,586	61,692
Accumulated Amortization	(44,532)	(36,921)
Total	24,054	24,771
Trademark
Finite-Lived Intangible Assets [Line Items]
Carrying amount, finite-lived intangible assets	32,711	27,195
Accumulated Amortization	(15,056)	(12,191)
Total	$ 17,655	$ 15,004
Backlog
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	1 year	1 year
Carrying amount, finite-lived intangible assets	$ 81,159	$ 82,355
Accumulated Amortization	(81,159)	(82,355)
Total	0	0
Other
Finite-Lived Intangible Assets [Line Items]
Carrying amount, finite-lived intangible assets	57,719	47,903
Accumulated Amortization	(39,426)	(31,501)
Total	$ 18,293	$ 16,402
Minimum | Customer related
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years	5 years
Minimum | Proprietary technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	4 years	7 years
Minimum | Trademark
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years	5 years
Minimum | Other
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years	3 years
Maximum | Customer related
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	26 years	26 years
Maximum | Proprietary technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	10 years	10 years
Maximum | Trademark
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	15 years	15 years
Maximum | Other
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	10 years	10 years

Other Intangible Assets (Remain

Other Intangible Assets (Remaining weighted-average amortization period) (Details)	12 Months Ended
	Sep. 30, 2022
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	6 years
Customer related
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	8 years
Proprietary technology
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	3 years
Trademark
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	6 years
Other
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	3 years

Other Intangible Assets (Estima

Other Intangible Assets (Estimated future amortization expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of Intangible Assets	$ 44,934	$ 37,385	$ 34,266
2022	44,421
2023	38,994
2024	33,960
2025	28,596
2026	24,070
Thereafter	113,485
Total	$ 283,526	$ 255,868

Debt (Schedule of Long-term Deb

Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Apr. 01, 2021
Debt Instrument [Line Items]
Total debt	$ 890,673	$ 754,943
Less unamortized deferred financing fees	(9,873)	(11,738)	$ (2,375)
Total net debt	880,800	743,205
Current portion of debt	(17,266)	(12,775)
Total long‑term debt	863,534	730,430
2021 Term Loan
Debt Instrument [Line Items]
Total debt	469,063	473,837
2021 Revolving Credit Facility, due April 2026
Debt Instrument [Line Items]
Total debt	151,254	37,268
Securitization Facility, due April 1, 2024
Debt Instrument [Line Items]
Total debt	150,201	150,061
Notes Payable due July 2023
Debt Instrument [Line Items]
Total debt	0	402
Equipment Financings | Equipment Financing
Debt Instrument [Line Items]
Total debt	$ 120,155	$ 93,375
Minimum | Equipment Financings | Equipment Financing
Debt Instrument [Line Items]
Interest Rate	3.59%
Maximum | Equipment Financings | Equipment Financing
Debt Instrument [Line Items]
Interest Rate	8.07%

Debt ( Credit Agreement, Term F

Debt ( Credit Agreement, Term Facilities and Revolving Credit Facility Narrative) (Details)			12 Months Ended
	Apr. 01, 2022 USD ($)	Apr. 01, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Line of Credit Facility [Line Items]
Unamortized discount (premium) and debt issuance costs, net		$ 2,375,000	$ 9,873,000	$ 11,738,000
Outstanding borrowings			890,673,000	754,943,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Proceeds from credit facility		105,000,000
Letter of Credit
Line of Credit Facility [Line Items]
Outstanding letters of credit			$ 9,317,000	$ 10,112,000
2021 Term Loan
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			2.50%	2.50%
Proceeds from secured debt		475,000,000
Debt instrument, periodic payment, principal		1,188,000
Outstanding borrowings			$ 469,063,000	$ 473,837,000
Debt instrument, interest rate			5.06%	2.63%
2021 Term Loan | LIBOR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			2.56%
2021 Revolving Credit Facility, due April 2026
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			2.20%	2.25%
Outstanding borrowings			$ 151,254,000	$ 37,268,000
Debt instrument, interest rate			5.33%	2.38%
Accrued interest			$ 254,000	$ 268,000
2021 Revolving Credit Facility, due April 2026 | LIBOR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			3.13%	0.13%
2014 Credit Agreement
Line of Credit Facility [Line Items]
Debt aggregate principal repaid	$ 814,538,000
Securitization Facility, due April 1, 2024
Line of Credit Facility [Line Items]
Outstanding borrowings			$ 150,201,000	$ 150,061,000
Accrued interest			$ 201,000	$ 61,000
2021 Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 350,000,000
Debt , covenant, maximum leverage ratio		5.55
2021 Credit Agreement | Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 60,000,000
2021 Credit Agreement | 2021 Term Loan
Line of Credit Facility [Line Items]
Debt instrument, face amount		$ 475,000,000

Debt (Schedule of Line of Credi

Debt (Schedule of Line of Credit Facilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Line of Credit Facility [Line Items]
Borrowing availability	$ 60,000	$ 60,000
Outstanding borrowings	890,673	754,943
Unused amounts	50,683	49,888
Revolving Credit Facility
Line of Credit Facility [Line Items]
Unused amounts	189,683	302,888
Letter of Credit
Line of Credit Facility [Line Items]
Outstanding letters of credit	9,317	10,112
2021 Revolving Credit Facility, due April 2026 | Revolving Credit Facility
Line of Credit Facility [Line Items]
Borrowing availability	350,000	350,000
Outstanding borrowings	$ 151,000	$ 37,000

Debt (Receivable Securitization

Debt (Receivable Securitization) (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 01, 2021	Sep. 30, 2022	Sep. 30, 2021
Line of Credit Facility [Line Items]
Outstanding borrowings		$ 890,673	$ 754,943
Securitization Facility, due April 1, 2024
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 150,000
Proceeds from credit facility	$ 142,200
Debt instrument, interest rate		4.39%	1.33%
Debt instrument, basis spread on variable rate		1.25%	1.25%
Securitization Facility, due April 1, 2024 | LIBOR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate		3.14%	0.08%

Debt (Equipment Financings) (De

Debt (Equipment Financings) (Details) - Equipment Financing $ in Thousands	12 Months Ended
	Sep. 30, 2022 USD ($)
Equipment Financing Due Sep 30 2032
Debt Instrument [Line Items]
Interest Rate	5.30%
Principal Amount	$ 3,811
Equipment Financing Due May 31, 2029 Sep 22 Draw
Debt Instrument [Line Items]
Interest Rate	5.03%
Principal Amount	$ 2,248
Equipment Financing Due Jul 31, 2029
Debt Instrument [Line Items]
Interest Rate	6.31%
Principal Amount	$ 12,356
Equipment Financing Due May 31. 2029 Jun 22 Draw
Debt Instrument [Line Items]
Interest Rate	5.03%
Principal Amount	$ 4,086
Equipment Financing Due Mar 17 2029
Debt Instrument [Line Items]
Interest Rate	4.67%
Principal Amount	$ 1,839
Equipment Financing Due Jul 31, 2029 Mar 22 Draw
Debt Instrument [Line Items]
Interest Rate	6.31%
Principal Amount	$ 1,317
Equipment Financing Due Apr 1 2029
Debt Instrument [Line Items]
Interest Rate	4.67%
Principal Amount	$ 4,788
Equipment Financing Due Dec 30, 2028
Debt Instrument [Line Items]
Interest Rate	3.94%
Principal Amount	$ 2,207
Equipment Financing Due July 31 2029 Draw Dec 23
Debt Instrument [Line Items]
Interest Rate	6.31%
Principal Amount	$ 3,742
Equipment Financings
Debt Instrument [Line Items]
Principal Amount	$ 36,394
Equipment Financing Due May 31 2029
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.75%
Equipment Financing Due May 31 2029 | Secured Overnight Financing Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.28%
Equipment Financing Due July 31 2029
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.75%
Equipment Financing Due July 31 2029 | LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.56%

Debt (Schedule of Deferred Fina

Debt (Schedule of Deferred Financing Fees and Discounts (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Apr. 01, 2021
Debt Instrument [Line Items]
Unamortized discount (premium) and debt issuance costs, net	$ 9,873	$ 11,738	$ 2,375
2014 Term Loan, due December 20, 2024
Debt Instrument [Line Items]
Unamortized discount (premium) and debt issuance costs, net	9,873	11,738
2014 Term Loan, due December 20, 2024 | Other Current Liabilities
Debt Instrument [Line Items]
Unamortized discount (premium) and debt issuance costs, net	1,899	1,866
2014 Term Loan, due December 20, 2024 | Other Noncurrent Liabilities
Debt Instrument [Line Items]
Unamortized discount (premium) and debt issuance costs, net	$ 7,974	$ 9,872

Debt (Deferred Financing Fees N

Debt (Deferred Financing Fees Narrative ) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Schedule of debt deferred financing costs and discounts [Line Items]
Write off of deferred debt issuance cost	$ 0	$ 1,333	$ 1,795
Amortization of debt issuance costs and discounts	$ 1,866	1,946	$ 1,735
Securitization Facility, due April 1, 2024
Schedule of debt deferred financing costs and discounts [Line Items]
Debt fees		822
Equipment Financings
Schedule of debt deferred financing costs and discounts [Line Items]
Debt fees		453
2014 Term Loan
Schedule of debt deferred financing costs and discounts [Line Items]
Write off of deferred debt issuance cost		1,333
Financing fees		4,985
Deferred financing fees		1,931
Debt fees expense		$ 3,054

Debt (Long-term Debt Maturities

Debt (Long-term Debt Maturities) (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Debt Disclosure [Abstract]
2023	$ 19,085
2024	167,870
2025	19,458
2026	173,775
2027	21,031
Thereafter	489,454
Total	$ 890,673

Derivative Financial Instrume_3

Derivative Financial Instruments (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2022 USD ($)
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ (186)
Description of Reclassification of Cash Flow Hedge Gain (Loss)	twelve months
Interest rate swaps
Derivative [Line Items]
Derivative, notional amount	$ 540,000
Foreign currency forward contracts
Derivative [Line Items]
Derivative, notional amount	26,106
Total return swaps—deferred compensation
Derivative [Line Items]
Derivative, notional amount	$ 5,629

Derivative Financial Instrume_4

Derivative Financial Instruments (Fair Values) (Details) - Fair Value, Recurring - Fair Value, Inputs, Level 2 - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	$ 49,952	$ 3,127
Interest rate swaps | Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Asset derivatives	19,186	3,127
Interest rate swaps | Designated as Hedging Instrument | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives	0	303
Interest rate swaps | Designated as Hedging Instrument | Other Assets
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	30,766	0
Foreign currency forward contracts | Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Asset derivatives	467	6
Foreign currency forward contracts | Designated as Hedging Instrument | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives	872	102
Commodity swaps | Designated as Hedging Instrument | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives	$ 7	$ 19

Derivative Financial Instrume_5

Derivative Financial Instruments (Amounts Recognized in AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized derivative gain (loss) on cash flow hedges, net of tax	$ 35,188	$ 7,293	$ (4,717)
Other Comprehensive Income (Loss) | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized derivative gain (loss) on cash flow hedges, net of tax	35,975	4,909	(5,375)
Interest rate swaps | Other Comprehensive Income (Loss) | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized derivative gain (loss) on cash flow hedges, net of tax	36,550	5,252	(5,155)
Interest rate cap | Other Comprehensive Income (Loss) | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized derivative gain (loss) on cash flow hedges, net of tax	0	0	(19)
Foreign currency forward contracts | Other Comprehensive Income (Loss) | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized derivative gain (loss) on cash flow hedges, net of tax	(583)	(324)	(201)
Commodity swaps | Other Comprehensive Income (Loss) | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized derivative gain (loss) on cash flow hedges, net of tax	$ 8	$ (19)	$ 0

Derivative Financial Instrume_6

Derivative Financial Instruments (Amounts Reclassified out of AOCI) (Details) - Reclassification out of Accumulated Other Comprehensive Income [Member] - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 787	$ (2,384)	$ (658)
Cost of services
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	(136)	(70)	(8)
General and administrative expense
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	(229)	(4)	(192)
Sales and marketing expense
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	0	(69)	28
Interest Expense
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 1,152	$ (2,241)	$ (486)

Derivative Financial Instrume_7

Derivative Financial Instruments (Derivatives Not Designated for Hedging) (Details) - Fair Value, Inputs, Level 2 - Fair Value, Recurring - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Asset derivatives	$ 40	$ 18
Other Current Liabilities | Total return swaps—deferred compensation
Derivatives, Fair Value [Line Items]
Liability derivatives	$ 632	$ 130

Derivative Financial Instrume_8

Derivative Financial Instruments (Location of Loss Recognized in Earnings) (Details) - General and administrative expense - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Loss on derivatives	$ (1,130)	$ (106)	$ 0
Total return swaps—deferred compensation
Derivative Instruments, Gain (Loss) [Line Items]
Loss on derivatives	$ (1,130)	$ (106)	$ 0

Product Warranties (Details)

Product Warranties (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Product Warranty Liability [Line Items]
Product Warranty Accrual, Current	$ 6,740	$ 8,138
Product warranties	3,465	2,966
Other Current Liabilities
Product Warranty Liability [Line Items]
Product Warranty Accrual, Current	6,740	8,138	$ 6,115	$ 4,922
Warranty provision for sales	6,732	6,939	4,738
Settlement of warranty claims	(7,206)	(4,720)	(4,890)
Foreign currency translation and other	(924)	(196)	550
Standard and Extended Product Warranty Accrual, Sale of Business	0	0	795
Other Noncurrent Liabilities
Product Warranty Liability [Line Items]
Product warranties	3,465	2,966	1,724	$ 2,332
Warranty provision for sales	2,835	2,065	701
Settlement of warranty claims	(2,022)	(830)	(1,170)
Foreign currency translation and other	(314)	7	(274)
Standard and Extended Product Warranty Accrual, Sale of Business	$ 0	$ 0	$ 135

Restructuring and Related Cha_3

Restructuring and Related Charges (Details) $ in Thousands		12 Months Ended
	Oct. 29, 2018 segment	Sep. 30, 2022 USD ($) segment	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Number of reportable segments | segment	3	2
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning of the period		$ 304	$ 970	$ 655
Restructuring charges related to two-segment realignment		5,586	9,149	12,135
Release of prior reserves		(300)	(329)	(98)
Write-off charges		0	(1,340)	(2,461)
Cash payments		(5,222)	(8,484)	(9,367)
Restructuring Reserve, Translation and Other Adjustment		(10)	9	8
Restructuring reserve, end of the period		658	304	970
Post Memcor product line sale
Restructuring Reserve [Roll Forward]
Restructuring charges related to two-segment realignment		979	5,588	8,274
Two-segment realignment
Restructuring Reserve [Roll Forward]
Restructuring charges related to two-segment realignment		390	1,060	2,092
Other Restructuring
Restructuring Reserve [Roll Forward]
Restructuring charges related to two-segment realignment		4,517	$ 2,830	$ 1,867
Other Restructuring | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost		8,400
Other Restructuring | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost		$ 9,400

Restructuring and Related Cha_4

Restructuring and Related Charges (Location of restructuring amounts) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 5,586	$ 9,149	$ 12,135
Cost of services
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2,217	4,554	8,305
General and administrative expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2,574	3,199	3,053
Sales and marketing expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	83	348	305
Research and development expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1	(16)	23
Other operating expense, net
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 711	$ 1,064	$ 449

Employee Benefit Plans - Narrat

Employee Benefit Plans - Narrative (Details) - USD ($) $ in Thousands			12 Months Ended
	Jan. 01, 2021	Apr. 01, 2014	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Matching contributions			$ 21,448	$ 16,559	$ 14,243
Deferred compensation plan, employer contribution percentage of participant's pay (up to)		6%
Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of deferral match percent	100%				100%
Deferred compensation arrangement with individual, cash awards granted, percentage			4%	6%
Discretionary profit sharing contribution			4%
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Matching contributions			$ 937	$ 919	$ 1,021

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Retirement Benefits [Abstract]
Service cost	$ 752	$ 1,156	$ 1,125
Interest cost	551	482	492
Expected return on plan assets	(771)	(615)	(387)
Amortization of actuarial losses	584	1,042	1,006
Pension expense for defined benefit plans	$ 1,116	$ 2,065	$ 2,236
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Operating Income (Expense), Net	Other Operating Income (Expense), Net	Other Operating Income (Expense), Net

Employee Benefit Plans Change i

Employee Benefit Plans Change in Projected Benefit Obligation and Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Change in projected benefit obligation
Service cost	$ 752	$ 1,156	$ 1,125
Interest cost	551	482	492
Pension Plan [Member] | Foreign Plan
Change in projected benefit obligation
Projected benefit obligation at prior year measurement date	46,013	47,389
Service cost	752	1,156
Interest cost	551	482
Actuarial gains	(13,069)	(2,312)
Benefits paid from company assets	(428)	(738)
Foreign currency exchange impact	(7,165)	36
Projected benefit obligation at measurement date	26,654	46,013	47,389
Change in plan assets
Fair value of assets at prior year measurement date	28,638	27,530
Actual return on plan assets	(4,639)	971
Benefits paid	(109)	(515)
Employer contribution	0	258
Foreign currency exchange impact	(4,600)	394
Fair value of assets at measurement date	19,290	28,638	$ 27,530
Funded status and amount recognized in assets and liabilities	(7,364)	(17,375)
Amount recognized in assets and liabilities
Other non‑current assets	1,779	2,960
Other non‑current liabilities	(9,143)	(20,335)
Amount recognized in accumulated other comprehensive loss, before taxes
Actuarial (gain) loss	$ (1,067)	$ 7,071

Employee Benefit Plans Projecte

Employee Benefit Plans Projected Benefit Obligation and Accumulated Benefit Obligation are in Excess of Plan Assets (Details) - Pension Plan [Member] - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 26,654	$ 46,013	$ 47,389
Fair value of plan assets	19,290	28,638	$ 27,530
GERMANY
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	26,654	46,013
Accumulated benefit obligation	14,621	24,578
Fair value of plan assets	$ 19,290	$ 28,638

Employee Benefit Plans Weighted

Employee Benefit Plans Weighted Average Assumptions (Details) - Pension Plan [Member]	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Minimum
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.03%	1%
Expected long‑term rate of return on plan assets	2.82%	1.97%
Salary scale	2.25%	2.25%
Pension increases	1%	1%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.97%	2.03%
Expected long‑term rate of return on plan assets	5.74%	3.50%
Salary scale	4.54%	4.36%
Pension increases	3.42%	3.27%

Employee Benefit Plans Allocati

Employee Benefit Plans Allocation of Plan Assets (Details) - UNITED KINGDOM	Sep. 30, 2022
Equity
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations, percentage	26.70%
Target plan assets allocation, percentage	0%
Index‑linked gilts
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations, percentage	72.80%
Target plan assets allocation, percentage	70%
Cash
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations, percentage	0.50%
Target plan assets allocation, percentage	30%

Employee Benefit Plans Benefits

Employee Benefit Plans Benefits expected to be paid (Details) - Pension Plan [Member] $ in Thousands	Sep. 30, 2022 USD ($)
Defined Benefit Plan Disclosure [Line Items]
2022	$ 880
2023	561
2024	648
2025	898
2026	828
Five years thereafter	7,616
Total	$ 11,432

Income Taxes (Additional Inform

Income Taxes (Additional Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Income Tax Contingency [Line Items]
Income tax benefit (expense)	$ 3,030	$ (10,080)	$ (7,371)
Tax expense increase (decrease)	13,110	2,709
Unrecognized tax benefits	1,035	1,123	1,050	$ 1,075
Penalties and interest accrued	$ (81)	(238)	(143)
Federal statutory income tax rate, percent	21%
Undistributed earnings of foreign subsidiaries	$ 119,524	77,709	53,766
Net operating loss carryforwards	40,124	48,605
Domestic Tax Authority
Income Tax Contingency [Line Items]
Operating loss carryforwards	156,887
State and Local Jurisdiction
Income Tax Contingency [Line Items]
Operating loss carryforwards	78,348
Foreign Tax Authority
Income Tax Contingency [Line Items]
Operating loss carryforwards	2,121
Foreign Tax Authority with Indefinite Expiration
Income Tax Contingency [Line Items]
Operating loss carryforwards	8,644
Other Current Liabilities
Income Tax Contingency [Line Items]
Unrecognized tax benefits	$ 1,593	$ 1,599	$ 1,288

Income Taxes Summary of Income

Income Taxes Summary of Income Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Domestic	$ 23,245	$ 19,927	$ 81,276
Foreign	46,068	41,815	40,490
Income before income taxes	$ 69,313	$ 61,742	$ 121,766

Income Taxes Components of Inco

Income Taxes Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Current:
Federal	$ 0	$ 0	$ 0
State	(932)	(1,233)	(591)
Foreign	(11,056)	(11,210)	(8,014)
Current income tax provision	(11,988)	(12,443)	(8,605)
Deferred:
Federal	9,470	(2,153)	115
State	6,168	(630)	401
Foreign	(620)	5,146	718
Deferred income tax provision	15,018	2,363	1,234
Income taxes	3,030	(10,080)	(7,371)
Income Tax Contingency [Line Items]
Income Tax Expense (Benefit)	$ (3,030)	$ 10,080	$ 7,371

Income Taxes Schedule of Effect

Income Taxes Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Tax Contingency [Line Items]
Income tax (expense) benefit at the federal statutory rate of 21%	$ (14,556)	$ (12,966)	$ (25,571)
State and local income taxes, net of federal tax benefit	989	(757)	(74)
Foreign tax rate differential	(1,897)	(3,009)	(1,129)
Nondeductible interest expense	(578)	(588)	(1,032)
Meals and entertainment expense	(36)	(176)	(760)
U.S. tax on foreign earnings	(2,683)	(5,687)	(8,438)
Other nondeductible expenses	(2,952)	(786)	(479)
Impact of tax rate changes	(24)	819	286
Valuation allowances	17,087	854	19,013
Share-based compensation	6,990	11,598	4,931
Non-taxable gain on sale of subsidiary	0	0	4,789
Return-to-provision adjustments	1,790	(44)	516
Non-controlling interest	31	30	(466)
Net benefit of foreign R&D expenses	0	0	18
Transaction related contingent liabilities	824	155	143
Deferred tax adjustments	(2,317)	87	491
Accrued tax adjustments	(138)	27	(6)
Other	500	363	397
Income taxes	$ 3,030	$ (10,080)	$ (7,371)

Income Taxes Schedule of Deferr

Income Taxes Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Receivable allowances	$ 1,619	$ 885
Reserves and accruals	23,706	24,913
Inventory valuation and other assets	4,196	3,141
Investment in partnership	0	1,977
Unrealized foreign exchange gains (losses), including related hedges	8,573	4,468
Right of use liabilities	12,021	0
Other deferred tax assets	1,052	2,811
Net operating loss carryforwards	40,124	48,605
Gross deferred tax assets	91,291	86,800
Less: Valuation allowance	(3,740)	(21,299)
Deferred Tax Assets, Net of Valuation Allowance	87,551	65,501
Goodwill	(8,162)	(9,849)
Fixed assets	(48,992)	(46,057)
Intangibles	(15,359)	(15,313)
Deferred Tax Liabilities, Other Comprehensive Income	(12,360)	0
Right of use assets	(11,291)	0
Other deferred tax liabilities	(1,751)	(2,440)
Gross deferred tax liabilities	(97,915)	(73,659)
Net deferred tax liabilities	$ (10,364)	$ (8,158)

Income Taxes Tax attributes ava

Income Taxes Tax attributes available to reduce future taxable income (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Operating Loss Carryforwards [Line Items]
Tax Credit Carryforward, Amount	$ 43
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	156,887
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	78,348
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	2,121
Foreign Tax Authority with Indefinite Expiration
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 8,644

Income Taxes Reconciliation of

Income Taxes Reconciliation of our valuation allowance on deferred tax assets (Details) - Valuation Allowance of Deferred Tax Assets - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation allowance beginning of period	$ 21,299	$ 23,298	$ 41,084
Change in assessment	(17,305)	(6,140)	1,650
Current year operations	217	7,300	(19,856)
Foreign currency and other	(471)	(3,219)	3,012
Acquisitions / Dispositions	0	60	2,592
Valuation allowance end of period	$ 3,740	$ 21,299	$ 23,298

Income Taxes Gross Unrecognized

Income Taxes Gross Unrecognized Tax Benefits Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance as of beginning of period	$ 1,123	$ 1,050	$ 1,075
Tax positions related to the current year	0	0	0
Tax positions related to prior years	0	73	0
Reductions	(88)	0	(25)
Expiration of statutes of limitations	0	0	0
Balance as of end of period	$ 1,035	$ 1,123	$ 1,050

Share Based Compensation (Narra

Share Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Oct. 01, 2018	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Dec. 21, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expensed and Capitalized, Amount		$ 23,450	$ 17,703	$ 10,535
Proceeds from issuance of common stock		9,556	$ 21,205	$ 10,091
Intrinsic value, exercised		$ 24,919
Weighted average grant date fair value, granted (in dollars per share)		$ 24.22	$ 9	$ 6.06
Fair value of options vested		$ 5,382	$ 4,434	$ 3,906
Share-based compensation		$ 22,104	$ 15,524	$ 10,509
Granted (shares)		2,000	612,000	823,000
Common stock, par value (in USD per share)		$ 0.01	$ 0.01
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (shares)		11,083,000
Number of shares available for grant (shares)		2,177,000
Compensation cost not yet recognized, period for recognition		$ 4,655
Period for recognition for unrecognized compensation expense		1 year 4 months 24 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (in shares)		507,000	240,000
Stock-settled RSU's (shares)		980,000	1,209,000	750,000
Compensation cost not yet recognized, period for recognition		$ 20,255
Period for recognition for unrecognized compensation expense		1 year 8 months 12 days
Special PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value, granted (in dollars per share)			$ 16.92
Stock-settled RSU's (shares)		592,000	469,000
Compensation cost not yet recognized, period for recognition		$ 9,710
Period for recognition for unrecognized compensation expense		1 year 9 months 18 days
Evoqua Water Technologies Corp. Stock Option Plan | Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards vesting percentage		25%
Award contractual term		10 years
Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance achievement measurement period		3 years
Award maximum payout, cannot exceed percentage		250%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period		3 years
Equity Incentive Plan | Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (shares)		3,977,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (shares)					11,297,000
Number of shares available for grant (shares)					5,000,000
Employee Stock Ownership Plan (ESOP), Compensation Expense		$ 1,011	$ 887	$ 392
Share-Based Compensation Arrangement by Share-Based Payment Award, Employee Purchase Stock Purchase, Percentage	85%
Common stock, par value (in USD per share)					$ 0.01
Employee Stock Purchase Plan | Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)		108,000	182,000	58,000

Share Based Compensation (Stock

Share Based Compensation (Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of the period (shares)	5,090,000	7,430,000
Granted (shares)	2,000	612,000	823,000
Exercised (shares)	(789,000)	(2,884,000)
Forfeited (shares)	(38,000)	(67,000)
Cancelled (shares)		(1,000)
Outstanding at end of the period (shares)	4,265,000	5,090,000	7,430,000
Options exercisable (shares)	3,223,000
Options vested and expected to vest (shares)	4,253,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted average exercise price, outstanding, beginning balance (in dollars per share)	$ 13.87	$ 10.30
Weighted average exercise price, granted (in dollars per share)	46.75	24.78
Weighted average exercise price, exercised (in dollars per share)	8.86	6.81
Weighted average exercise price, forfeited (in dollars per share)	21.05	21.25
Weighted average exercise price, expired (in dollars per share)		16.63
Weighted average exercise price, outstanding, ending balance (in dollars per share)	14.74	$ 13.87	$ 10.30
Weighted average exercise price, exercisable (in dollars per share)	12.51
Weighted average exercise price, options vested and expected to vest (in dollars per share)	$ 14.72
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual term, outstanding	5 years 2 months 12 days	5 years 10 months 24 days	5 years 10 months 24 days
Weighted average remaining contractual term, exercisable	4 years 4 months 24 days
Weighted average remaining contractual term, options vested and expected to vest	5 years 2 months 12 days
Aggregate intrinsic value, outstanding	$ 78,218	$ 120,611	$ 83,152
Aggregate intrinsic value, exercised	(24,919)
Aggregate intrinsic value, exercisable	66,272
Aggregate intrinsic value, options vested and expected to vest, outstanding	$ 78,093

Share Based Compensation (Nonve

Share Based Compensation (Nonvested Share Activity) (Details) - $ / shares	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Unvested at beginning of period	1,901,000	2,166,000	2,379,000
Granted (shares)	2,000	612,000	823,000
Vested (shares)	(823,000)	(810,000)	(864,000)
Forfeited (shares)	(38,000)	(67,000)	(172,000)
Unvested at end of period	1,042,000	1,901,000	2,166,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, nonvested, beginning balance (in dollars per share)	$ 6.69	$ 5.56	$ 4.96
Weighted average grant date fair value, granted (in dollars per share)	24.22	9	6.06
Weighted average grant date fair value, vested (in dollars per share)	6.54	5.48	4.52
Weighted average grant date fair value, forfeited (in dollars per share)	6.87	6.82	4.94
Weighted average grant date fair value, nonvested, ending balance (in dollars per share)	$ 6.82	$ 6.69	$ 5.56

Share Based Compensation (RSU A

Share Based Compensation (RSU Activity) (Details) - $ / shares shares in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Forfeited (in shares)	(1)
Vested and expected to vest (shares)	3,223
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average exercise price, vested and expected to vest (in dollars per share)	$ 14.72
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at beginning of the period (shares)	1,209	750
Granted (shares)	328	731
Vested (in shares)	(507)	(240)
Forfeited (in shares)	(50)	(25)
Cancelled (in shares)		(7)
Outstanding at the end of the period (in shares)	980	1,209
Vested and expected to vest (shares)	959
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, nonvested, equity instruments other than options, beginning of the period (in dollar per share)	$ 22.77	$ 17.86
Weighted average grant date fair value, granted (in dollars per share)	44.88	25.98
Weighted average grant date fair value, vested and expected to vest (in dollars per share)	22.23	17.55
Weighted average grant date fair value, forfeited (in dollars per share)	27.96	20.31
Weighted average grant date fair value, cancelled (in dollars per share)		21.22
Weighted average grant date fair value, nonvested, equity instruments other than options, end of the period (in dollar per share)	30.18	$ 22.77
Weighted average exercise price, vested and expected to vest (in dollars per share)	$ 30.05
Special PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at beginning of the period (shares)	469
Granted (shares)	124	469
Outstanding at the end of the period (in shares)	592	469
Vested and expected to vest (shares)	555
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, nonvested, equity instruments other than options, beginning of the period (in dollar per share)	$ 16.92
Weighted average grant date fair value, granted (in dollars per share)	52.50	$ 16.92
Weighted average grant date fair value, forfeited (in dollars per share)	47.92
Weighted average grant date fair value, nonvested, equity instruments other than options, end of the period (in dollar per share)	23.36	$ 16.92
Weighted average exercise price, vested and expected to vest (in dollars per share)	$ 23.25

Share Based Compensation (Valua

Share Based Compensation (Valuation Assumptions for Options Granted) (Details) - $ / shares	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free rate		0.34%
Weighted average grant date fair value, granted (in dollars per share)	$ 24.22	$ 9	$ 6.06
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	55.30%
Expected volatility, minimum		38.30%	24.20%
Expected volatility, maximum		56.70%	77.10%
Expected term (in years)	5 years 10 months 24 days
Stock Option | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		5 years 3 months 18 days	5 years 4 months 24 days
Risk free rate	1.40%	0.40%	0.20%
Grant date fair value per share of options granted (in dollars per share)	$ 24.22	$ 8.12	$ 5.33
Stock Option | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		6 years	6 years
Risk free rate		0.90%	1.70%
Grant date fair value per share of options granted (in dollars per share)		$ 19.76	$ 8.56
Special PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility		61%
Expected volatility, minimum	56%
Expected volatility, maximum	56.20%
Expected term (in years)	3 years	3 years
Weighted average grant date fair value, granted (in dollars per share)		$ 16.92
Special PSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free rate	0.91%
Weighted average grant date fair value, granted (in dollars per share)	$ 46.08
Special PSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free rate	1.13%
Weighted average grant date fair value, granted (in dollars per share)	$ 52.57

Share Based Compensation (Share

Share Based Compensation (Share-based compensation expense classified in the Consolidated Statements of Operations) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 22,104	$ 15,524	$ 10,509
Cost of services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	234	143	91
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 21,870	$ 15,381	$ 10,418

Other Comprehensive Loss (Compo

Other Comprehensive Loss (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive income	$ 710,093	$ 582,219	$ 482,063	$ 365,822
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive income	6,767	16,137
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive income	(1,776)	(7,474)
Other comprehensive income (loss), tax expense (benefit)	(2,790)	(403)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive income	37,940	2,752
Other comprehensive income (loss), tax expense (benefit)	(11,770)	(135)
Accumulated Other Comprehensive (Loss) Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive income	$ 42,931	$ 11,415	$ (20,472)	$ (13,004)

Other Comprehensive Loss (Gains

Other Comprehensive Loss (Gains (losses) in Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	$ 580,671
Accumulated other comprehensive income (loss), ending balance	710,093	$ 580,671
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	16,137	(5,535)	$ (2,705)
Other comprehensive loss before reclassifications	(9,370)	21,672	(2,830)
Amounts gains reclassified from accumulated other comprehensive loss into earnings	0	0	0
Accumulated other comprehensive income (loss), ending balance	6,767	16,137	(5,535)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	(7,474)	(10,396)	(10,475)
Other comprehensive loss before reclassifications	5,114	1,880	(927)
Amounts gains reclassified from accumulated other comprehensive loss into earnings	584	1,042	1,006
Accumulated other comprehensive income (loss), ending balance	(1,776)	(7,474)	(10,396)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	2,752	(4,541)	176
Other comprehensive loss before reclassifications	35,975	4,909	(5,375)
Amounts gains reclassified from accumulated other comprehensive loss into earnings	(787)	2,384	658
Accumulated other comprehensive income (loss), ending balance	$ 37,940	$ 2,752	$ (4,541)

Concentration of Credit Risk (D

Concentration of Credit Risk (Details)	Sep. 30, 2022 country
Risks and Uncertainties [Abstract]
Number of countries in which entity operates	9

Concentration of Credit Risk -

Concentration of Credit Risk - External net revenue, net of intercompany eliminations, and net asset information by region (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 1,737,076	$ 1,464,429	$ 1,429,456
Net Assets	710,093	582,219
Property, plant, and equipment, net	405,289	374,988
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	1,431,095	1,174,474	1,164,634
Net Assets	558,512	462,883
Property, plant, and equipment, net	388,591	357,597
Rest of World
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	305,981	289,955	$ 264,822
Net Assets	151,581	119,336
Property, plant, and equipment, net	$ 16,698	$ 17,391

Leases (Leases, Lessee Disclosu

Leases (Leases, Lessee Disclosures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Amortization of ROU assets	$ 13,461	$ 13,572	$ 13,738
Interest on lease liabilities	1,574	1,793	1,981
Operating lease cost	16,529	15,357	16,052
Short-term lease cost	875	2,935	4,970
Sublease income	0	(58)	(56)
Total lease cost	32,439	33,599	36,685
Operating cash flows from finance leases	1,573	1,810	1,968
Operating cash flows from operating leases	17,178	15,758	16,034
Financing cash flows from finance leases	13,356	13,373	13,459
ROU assets obtained in exchange for new finance lease liabilities	15,329	14,257	14,934
ROU assets obtained in exchange for new operating lease liabilities	14,151	4,839	8,456
ROU asset remeasurement	$ 6,723	$ 8,177	$ (960)
Weighted average remaining lease term - finance leases	3 years 6 months	3 years 7 months 6 days	3 years 10 months 24 days
Weighted average remaining lease term - operating leases	4 years 7 months 6 days	4 years 9 months 18 days	5 years 2 months 12 days
Weighted average discount rate - finance leases	4.20%	4.30%	4.60%
Weighted average discount rate - operating leases	4.20%	4%	4.20%

Leases (Operating Leases Future

Leases (Operating Leases Future Payments) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Leases [Abstract]
2022	$ 16,995
2023	14,927
2024	12,585
2025	9,345
2026	5,815
Thereafter	4,788
Total undiscounted lease payments	64,455
Present value adjustment	(5,562)
Operating lease liabilities	$ 58,893
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Less current installments of obligations under operating leases	$ 14,932	$ 13,316
Obligations under operating leases, excluding current installments	$ 43,961	$ 37,935

Leases (Finance Lease Assets) (

Leases (Finance Lease Assets) (Details) - Equipment - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Lessee, Lease, Description [Line Items]
Gross carrying amount	$ 85,217	$ 92,247
Net carrying amount	$ 37,715	$ 36,884

Leases (Finance Lease Maturitie

Leases (Finance Lease Maturities) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Leases [Abstract]
2022	$ 14,220
2023	11,669
2024	8,674
2025	5,132
2025	1,938
Thereafter	209
Total undiscounted lease payments	41,842
Present value adjustment	(2,779)
Finance lease liabilities	$ 39,063
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Less current installments of obligations under finance leases	$ 12,875	$ 12,093
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other non‑current liabilities
Obligations under finance leases, excluding current installments	$ 26,188

Leases (Components of Lease Rev

Leases (Components of Lease Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Lease revenue: operating leases	$ 164,574	$ 152,435	$ 148,703
Sales-Type Lease, Lease Income, Statement of Income or Comprehensive Income [Extensible Enumeration]	Sales to external customers	Sales to external customers	Sales to external customers
Lease revenue: sales-type leases	$ 16,937	$ 37,898	$ 981
Lease Income	$ 181,511	$ 190,333	$ 149,684
Operating Lease, Lease Income, Statement of Income or Comprehensive Income [Extensible Enumeration]	Sales to external customers	Sales to external customers	Sales to external customers

Leases (Lessor Operating Lease

Leases (Lessor Operating Lease Future Receivables) (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Leases [Abstract]
2022	$ 165,025
2023	99,403
2024	69,620
2025	46,650
2026	34,700
Thereafter	181,314
Lessor, Operating Lease, Payments to be Received	$ 596,712

Leases (Sales Type Leases) (Det

Leases (Sales Type Leases) (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Fiscal year
2022	$ 3,001
2023	4,128
2024	4,128
2025	4,128
2026	4,128
Thereafter	34,970
Total	54,483
Prepaid Expenses and Other Current Assets
Lessee, Lease, Description [Line Items]
Lease receivable	3,001
Other Noncurrent Assets
Lessee, Lease, Description [Line Items]
Lease receivable	$ 51,482

Commitments and Contingencies_2

Commitments and Contingencies (Schedule of Letters of Credit and Surety Bonds) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Other Commitments [Line Items]
Line of credit facility, remaining borrowing capacity	$ 60,000	$ 60,000
Debt instrument, unused borrowing capacity, amount	50,683	49,888
Surety Bond [Member]
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	261,959	250,000
Guarantor Obligations, Current Carrying Value	134,037	147,845
Guarantor Obligations, Remaining Surety Bonds Available	$ 127,922	$ 102,155
Minimum | Surety Bond [Member]
Other Commitments [Line Items]
Letter of Credit, Guarantee, Bond Commitments, Expiration Period	12 months
Maximum | Surety Bond [Member]
Other Commitments [Line Items]
Letter of Credit, Guarantee, Bond Commitments, Expiration Period	10 years

Accrued Expenses and Other Li_3

Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Payables and Accruals [Abstract]
Salaries, wages, and other benefits	$ 83,618	$ 79,110
Obligation under operating leases	$ 14,932	$ 13,316
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Obligation under finance leases	$ 12,875	$ 12,093
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Third party commissions	$ 10,341	$ 10,031
Deferred revenue	9,692	5,241
Taxes, other than income	5,594	4,575
Insurance liabilities	3,456	3,720
Provisions for litigation	2,375	2,938
Fair value of liability derivatives	1,511	554
Severance payments	658	304
Earn-outs related to acquisitions	0	150
Other	33,220	28,335
Accrued expenses and other liabilities	$ 178,272	$ 160,367

Business Segments (Details)

Business Segments (Details) $ in Thousands		12 Months Ended
	Oct. 29, 2018 segment	Sep. 30, 2022 USD ($) segment	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment	3	2
Segment Reporting Information [Line Items]
Revenue		$ 1,737,076	$ 1,464,429	$ 1,429,456
Sales to external customers		1,737,076	1,464,429	1,429,456
Earnings before interest, taxes, depreciation and amortization (EBITDA)		103,993	99,317	168,448
Depreciation and amortization		127,570	113,664	107,268
Interest expense		(34,680)	(37,575)	(46,682)
Income before income taxes		69,313	61,742	121,766
Income tax benefit (expense)		3,030	(10,080)	(7,371)
Net income		72,343	51,662	114,395
Capital expenditures		82,045	75,293	88,456
Assets		2,190,863	1,868,891
Goodwill		473,572	407,376	397,205
Integrated Solutions and Services
Segment Reporting Information [Line Items]
Sales to external customers		1,184,477	959,886	944,182
Capital expenditures		66,897	60,407	75,551
Goodwill				224,381
Applied Product Technologies
Segment Reporting Information [Line Items]
Sales to external customers		552,599	504,543	485,274
Capital expenditures		6,704	6,955	6,237
Goodwill				172,824
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue		1,875,410	1,568,932	1,514,177
Operating Segments [Member] | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Revenue		1,222,165	980,852	954,542
Sales to external customers		1,184,477		944,182
Earnings before interest, taxes, depreciation and amortization (EBITDA)		165,562	147,251	145,655
Depreciation and amortization		83,866	70,585	67,489
Assets		1,123,166	887,265
Goodwill		306,935	233,830
Operating Segments [Member] | Applied Product Technologies
Segment Reporting Information [Line Items]
Revenue		653,245	588,080	559,635
Sales to external customers		552,599		485,274
Earnings before interest, taxes, depreciation and amortization (EBITDA)		103,087	82,891	134,258
Depreciation and amortization		13,918	14,423	14,226
Assets		653,244	656,362
Goodwill		166,637	173,546
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Sales to external customers		138,334	104,503	84,721
Intersegment Eliminations [Member] | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Sales to external customers		37,688	20,966	10,360
Intersegment Eliminations [Member] | Applied Product Technologies
Segment Reporting Information [Line Items]
Sales to external customers		100,646	83,537	74,361
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Earnings before interest, taxes, depreciation and amortization (EBITDA)		(164,656)	(130,825)	(111,465)
Depreciation and amortization		29,786	28,656	25,553
Capital expenditures		8,444	7,931	$ 6,668
Assets		$ 414,453	$ 325,264

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net income attributable to Evoqua Water Technologies Corp.	$ 72,198	$ 51,482	$ 113,649
Denominator:
Denominator for basic net income per common share—weighted average shares	121,138	119,575	116,721
Effect of dilutive securities:
Share‑based compensation	3,744	3,368	4,342
Denominator for diluted net loss per common share—adjusted weighted average shares	124,882	122,943	121,063
Basic income per common share	$ 0.60	$ 0.43	$ 0.97
Diluted income per common share	$ 0.58	$ 0.42	$ 0.94
Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	474	1,784	2,512

SCHEDULE_I - Evoqua Water Tec_3

SCHEDULE I - Evoqua Water Technologies Corp. Condensed Consolidated Balance Sheets (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Condensed Financial Statements, Captions [Line Items]
Current assets	$ 831,389	$ 678,458
Cash and cash equivalents	134,005	146,244
Prepaid and other current assets	59,971	21,871
Total assets	2,190,863	1,868,891
LIABILITIES AND EQUITY
Total liabilities	1,480,770	1,286,672
Common stock, par value $0.01: authorized 1,000,000 shares; issued 123,411 shares, outstanding 121,747 at September 30, 2022; issued 122,173 shares, outstanding 120,509 at September 30, 2021	1,235	1,223
Treasury stock: 1,664 shares at September 30, 2022 and 1,664 shares at September 30, 2021	(2,837)	(2,837)
Additional paid‑in capital	607,748	582,052
Retained earnings (deficit)	61,016	(11,182)
Total shareholders’ equity	710,093	580,671
Total liabilities and shareholders’ equity	$ 2,190,863	$ 1,868,891
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares, issued (in shares)	123,411,000	122,173,000
Common stock, outstanding (in shares)	121,747,000	120,509,000
Treasury stock, shares (in shares)	1,664,000	1,664,000
Parent Company
Condensed Financial Statements, Captions [Line Items]
Current assets	$ 67,403	$ 51,777
Due from Affiliates	62,080	39,982
Cash and cash equivalents	5,202	11,681
Prepaid and other current assets	121	114
Investment in affiliate	600,064	517,479
Total assets	667,467	569,256
LIABILITIES AND EQUITY
Other current liabilities	305	0
Total liabilities	305	0
Common stock, par value $0.01: authorized 1,000,000 shares; issued 123,411 shares, outstanding 121,747 at September 30, 2022; issued 122,173 shares, outstanding 120,509 at September 30, 2021	1,235	1,223
Treasury stock: 1,664 shares at September 30, 2022 and 1,664 shares at September 30, 2021	(2,837)	(2,837)
Additional paid‑in capital	607,748	582,052
Retained earnings (deficit)	61,016	(11,182)
Total shareholders’ equity	667,162	569,256
Total liabilities and shareholders’ equity	$ 667,467	$ 569,256

SCHEDULE_I - Evoqua Water Tec_4

SCHEDULE I - Evoqua Water Technologies Corp. Condensed Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Condensed Financial Statements, Captions [Line Items]
General and administrative expense	$ (260,550)	$ (206,455)	$ (192,597)
Income tax benefit (expense)	3,030	(10,080)	(7,371)
Net income attributable to Evoqua Water Technologies Corp.	72,198	51,482	113,649
Parent Company
Condensed Financial Statements, Captions [Line Items]
Other operating income	8	(1,073)	16
General and administrative expense	(454)	(426)	(476)
Net income of subsidiaries	72,644	52,981	114,109
Income before income taxes	72,198	51,482	113,649
Income tax benefit (expense)	0	$ 0	0
Net income attributable to Evoqua Water Technologies Corp.	$ 72,198		$ 113,649

SCHEDULE_I - Evoqua Water Tec_5

SCHEDULE I - Evoqua Water Technologies Corp. Condensed Statements of Changes in Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Operating activities
Net income	$ 72,343	$ 51,662	$ 114,395
Reconciliation of net income to cash flows provided by operating activities:
Foreign currency exchange losses (gains) on intercompany loans and other non-cash items	18,778	(1,094)	(8,202)
Changes in assets and liabilities
Accrued expenses and other liabilities	13,943	21,881	22,078
Prepaids and other current assets	(13,173)	260	2,088
Net cash provided by operating activities	181,402	178,705	177,026
Investing activities
Net cash (used in) provided by investing activities	(310,694)	(97,172)	11,992
Financing activities
Proceeds from issuance of common stock	9,556	21,205	10,091
Taxes paid related to net share settlements of share-based compensation awards	(6,281)	(1,323)	(9,832)
Net cash (used in) provided by financing activities	125,548	(130,344)	(108,117)
Change in cash and cash equivalents	(12,239)	(46,757)	83,120
Beginning of period	146,244	193,001	109,881
End of period	134,005	146,244	193,001
Parent Company
Operating activities
Net income	72,198	51,482	113,649
Reconciliation of net income to cash flows provided by operating activities:
Net (loss) income of subsidiaries	(72,644)	(52,981)	(114,109)
Foreign currency exchange losses (gains) on intercompany loans and other non-cash items	0	0	(15)
Changes in assets and liabilities
Due from affiliates	(9,606)	(11,638)	5,842
Due to affiliates	0	0	(9,747)
Accrued expenses and other liabilities	305	0	160
Prepaids and other current assets	(7)	(36)	(24)
Net cash provided by operating activities	(9,754)	(13,173)	(4,244)
Investing activities
Contributed capital	0	0	0
Net cash (used in) provided by investing activities	0	0	0
Financing activities
Proceeds from issuance of common stock		21,205	18,927
Taxes paid related to net share settlements of share-based compensation awards	(6,281)	(1,323)	(9,832)
Net cash (used in) provided by financing activities	3,275	19,882	9,095
Change in cash and cash equivalents	(6,479)	6,709	4,851
Beginning of period	11,681	4,972	121
End of period	$ 5,202	$ 11,681	$ 4,972

SCHEDULE_I - Evoqua Water Tec_6

SCHEDULE I - Evoqua Water Technologies Corp. (Details) - USD ($)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Apr. 01, 2021
Debt Instrument [Line Items]
Outstanding borrowings	$ 890,673,000	$ 754,943,000
2021 Term Loan
Debt Instrument [Line Items]
Outstanding borrowings	469,063,000	473,837,000
2021 Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 350,000,000
2021 Credit Agreement | 2021 Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount			$ 475,000,000
Parent Company
Debt Instrument [Line Items]
Cash dividends paid by consolidated subsidiaries	0	0
Parent Company | 2021 Credit Agreement
Debt Instrument [Line Items]
Outstanding borrowings	$ 620,317,000	$ 511,105,000