Evoqua Water Technologies (AQUA) 10-Q 6 Aug 19 2019 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information Statement - shares	9 Months Ended
	Jun. 30, 2019	Jul. 31, 2019
Document Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2019
Entity Registrant Name	EVOQUA WATER TECHNOLOGIES CORP.
Entity Central Index Key	0001604643
Current Fiscal Year End Date	--09-30
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		114,343,957
Entity Current Reporting Status	Yes

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
ASSETS
Current assets	$ 565,088	$ 565,560
Cash and cash equivalents	61,122	82,365
Receivables, net	247,717	254,756
Inventories, net	161,020	134,988
Contract assets	70,018	69,147
Prepaid and other current assets	25,205	23,854
Income tax receivable	6	450
Property, plant, and equipment, net	341,404	320,023
Goodwill	410,286	411,346
Intangible assets, net	323,321	340,408
Deferred income taxes	7,239	2,438
Other non‑current assets	24,117	23,842
Total assets	1,671,455	1,663,617
LIABILITIES AND EQUITY
Current liabilities	281,696	284,719
Accounts payable	137,480	141,140
Current portion of debt	12,661	11,555
Contract liabilities	32,312	17,652
Product warranties	8,264	8,907
Accrued expenses and other liabilities	89,273	97,672
Income tax payable	1,706	7,793
Non‑current liabilities	1,026,168	1,016,882
Long‑term debt	935,507	928,075
Product warranties	3,741	3,360
Other non‑current liabilities	75,786	74,352
Deferred income taxes	11,134	11,095
Total liabilities	1,307,864	1,301,601
Commitments and Contingent Liabilities (Note 19)
Shareholders’ equity
Common stock, par value $0.01: authorized 1,000,000 shares; issued 115,968 shares, outstanding 114,312 shares at June 30, 2019; issued 115,016 shares, outstanding 113,929 shares at September 30, 2018	1,154	1,145
Treasury stock: 1,656 shares at June 30, 2019 and 1,087 shares at September 30, 2018	(2,837)	(2,837)
Additional paid‑in capital	546,767	533,435
Retained deficit	(176,483)	(163,871)
Accumulated other comprehensive loss, net of tax	(8,207)	(9,017)
Total Evoqua Water Technologies Corp. equity	360,394	358,855
Non‑controlling interest	3,197	3,161
Total shareholders’ equity	363,591	362,016
Total liabilities and shareholders’ equity	$ 1,671,455	$ 1,663,617

Consolidated Balance Sheets Con

Consolidated Balance Sheets Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2019	Sep. 30, 2018
Statement of Financial Position [Abstract]
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	1,000,000,000	1,000,000,000
Common stock issued (in shares)	115,968,000	115,016,000
Common stock outstanding (in shares)	114,312,000	113,929,000
Treasury stock (in shares)	1,656,000	1,087,000

Unaudited Consolidated Statemen

Unaudited Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues [Abstract]
Revenue from product sales and services	$ 360,343	$ 342,475	$ 1,031,973	$ 973,215
Cost of Revenue [Abstract]
Cost of product sales and services	(249,049)	(240,468)	(736,338)	(674,832)
Gross profit	111,294	102,007	295,635	298,383
Operating Expenses [Abstract]
General and administrative expense	(49,525)	(56,961)	(152,571)	(140,767)
Sales and marketing expense	(31,959)	(33,888)	(103,546)	(102,459)
Research and development expense	(3,281)	(3,682)	(11,384)	(12,356)
Total operating expenses	(84,765)	(94,531)	(267,501)	(255,582)
Other operating income	746	8,458	4,625	9,396
Other operating expense	(184)	(1,096)	(559)	(1,722)
Interest expense	(14,842)	(12,370)	(43,759)	(40,423)
Income (loss) before income taxes	12,249	2,468	(11,559)	10,052
Income tax (expense) benefit	(7,959)	(1,433)	1,134	960
Net income (loss)	4,290	1,035	(10,425)	11,012
Net income attributable to non‑controlling interest	155	242	786	1,427
Net income (loss) attributable to Evoqua Water Technologies Corp.	$ 4,135	$ 793	$ (11,211)	$ 9,585
Basic loss per common share (in dollars per share)	$ 0.04	$ 0.01	$ (0.10)	$ 0.08
Diluted loss per common share (in dollars per share)	$ 0.03	$ 0.01	$ (0.10)	$ 0.08
Revenue from product sales
Revenues [Abstract]
Revenue from product sales and services	$ 210,363	$ 211,486	$ 597,319	$ 582,973
Cost of Revenue [Abstract]
Cost of product sales and services	(148,417)	(140,345)	(438,869)	(389,980)
Revenue from service
Revenues [Abstract]
Revenue from product sales and services	149,980	130,989	434,654	390,242
Cost of Revenue [Abstract]
Cost of product sales and services	$ (100,632)	$ (100,123)	$ (297,469)	$ (284,852)

Unaudited Consolidated Statem_2

Unaudited Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Other comprehensive (loss) income
Net income (loss)	$ 4,290	$ 1,035	$ (10,425)	$ 11,012
Foreign currency translation adjustments	(341)	(2,015)	1,241	(2,811)
Unrealized derivative loss on cash flow hedges, net of tax	(251)	(3)	(431)	0
Total other comprehensive (loss) income	(592)	(2,018)	810	(2,811)
Less: Comprehensive income attributable to non‑controlling interest	(155)	(242)	(786)	(1,427)
Comprehensive income (loss) attributable to Evoqua Water Technologies Corp.	$ 3,543	$ (1,225)	$ (10,401)	$ 6,774

Unaudited Consolidated Statem_3

Unaudited Consolidated Statements of Comprehensive (Loss) Income (Parenthetical) - USD ($)	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Change in cash flow hedges, tax	$ 0	$ 0	$ 0	$ 0

Unaudited Consolidated Statem_4

Unaudited Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Cost	Cost	Additional Paid‑in Capital	Retained Deficit	Accumulated Other Comprehensive Loss	Non‑controlling Interest
Common stock issued at the beginning of the period (shares) at Sep. 30, 2017		105,359,000
Stockholders' equity, balance at the beginning of the period at Sep. 30, 2017	$ 216,575	$ 1,054	$ (2,607)	$ 388,986	$ (170,006)	$ (5,989)	$ 5,137
Treasury stock, balance at the beginning of the period (in shares) at Sep. 30, 2017			410,000
Equity based compensation expense	11,257
Issuance of common stock (in shares)		8,333,000
Issuance of common stock, cost		$ 83		137,522
Proceeds from issuance of common stock	137,605
Shares withheld related to net share settlement (including tax withholdings) (shares)		1,079,000	532,000
Shares withheld related to net share settlement (including tax withholdings)	(7,767)	$ 6		(7,773)
Stock repurchases (shares)			18,000
Stock repurchases	(230)		$ (230)
Dividends paid to non-controlling interest	(2,425)						(2,425)
Net income (loss)	11,012				9,585		1,427
Other comprehensive income	(2,811)
Common stock issued at the end of the period (shares) at Jun. 30, 2018		114,771,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2018	363,216	$ 1,143	$ (2,837)	529,992	(160,421)	(8,800)	4,139
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2018			960,000
Other Comprehensive Income (Loss), Net of Tax	(2,811)
Stock repurchases	(230)
Net income attributable to non‑controlling interest	1,427
Common stock issued at the beginning of the period (shares) at Mar. 31, 2018		114,710,000
Stockholders' equity, balance at the beginning of the period at Mar. 31, 2018	361,076	$ 1,142	$ (2,837)	525,997	(161,216)	(6,782)	4,772
Treasury stock, balance at the beginning of the period (in shares) at Mar. 31, 2018			941,000
Equity based compensation expense	4,395
Issuance of common stock (in shares)		0
Issuance of common stock, cost		$ 0		0
Proceeds from issuance of common stock	0
Shares withheld related to net share settlement (including tax withholdings) (shares)		61,000	19,000
Shares withheld related to net share settlement (including tax withholdings)	(399)	$ 1		(400)
Stock repurchases (shares)			0
Stock repurchases	0		$ 0
Dividends paid to non-controlling interest	(875)						(875)
Net income (loss)	1,035				793		242
Other comprehensive income	(2,018)
Common stock issued at the end of the period (shares) at Jun. 30, 2018		114,771,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2018	363,216	$ 1,143	$ (2,837)	529,992	(160,421)	(8,800)	4,139
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2018			960,000
Other Comprehensive Income (Loss), Net of Tax	(2,018)
Net income attributable to non‑controlling interest	242
Cumulative effect of adoption of new accounting standards	$ (1,401)				(1,401)
Common stock issued at the beginning of the period (shares) at Sep. 30, 2018	115,016,000	115,016,000
Stockholders' equity, balance at the beginning of the period at Sep. 30, 2018	$ 362,016	$ 1,145	$ (2,837)	533,435	(163,871)	(9,017)	3,161
Treasury stock, balance at the beginning of the period (in shares) at Sep. 30, 2018	1,087,000		1,087,000
Equity based compensation expense	$ 14,248
Issuance of common stock (in shares)		108,000
Issuance of common stock, cost				341
Proceeds from issuance of common stock	341
Shares withheld related to net share settlement (including tax withholdings) (shares)		844,000	569,000
Shares withheld related to net share settlement (including tax withholdings)	(1,248)	$ 9		(1,257)
Dividends paid to non-controlling interest	(750)						(750)
Net income (loss)	(10,425)				(11,211)
Other comprehensive income	$ 810
Common stock issued at the end of the period (shares) at Jun. 30, 2019	115,968,000	115,968,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2019	$ 363,591	$ 1,154	$ (2,837)	546,767	(176,483)	(8,207)	3,197
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2019	1,656,000		1,656,000
Other Comprehensive Income (Loss), Net of Tax	$ 810
Stock repurchases	0
Net income attributable to non‑controlling interest	786
Common stock issued at the beginning of the period (shares) at Mar. 31, 2019		115,691,000
Stockholders' equity, balance at the beginning of the period at Mar. 31, 2019	355,377	$ 1,151	$ (2,837)	542,104	(180,618)	(7,615)	3,192
Treasury stock, balance at the beginning of the period (in shares) at Mar. 31, 2019			1,518,000
Equity based compensation expense	4,978
Issuance of common stock (in shares)		46,000
Issuance of common stock, cost				0
Proceeds from issuance of common stock	0
Shares withheld related to net share settlement (including tax withholdings) (shares)		231,000	138,000
Shares withheld related to net share settlement (including tax withholdings)	(312)	$ 3		(315)
Stock repurchases (shares)			0
Stock repurchases			$ 0
Dividends paid to non-controlling interest	(150)						(150)
Net income (loss)	4,290				4,135
Other comprehensive income	$ (592)
Common stock issued at the end of the period (shares) at Jun. 30, 2019	115,968,000	115,968,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2019	$ 363,591	$ 1,154	$ (2,837)	$ 546,767	$ (176,483)	$ (8,207)	$ 3,197
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2019	1,656,000		1,656,000
Other Comprehensive Income (Loss), Net of Tax	$ (592)
Stock repurchases	0
Net income attributable to non‑controlling interest	$ 155

Unaudited Consolidated Statem_5

Unaudited Consolidated Statements of Changes in Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Operating activities
Net (loss) income	$ (10,425)	$ 11,012
Reconciliation of net (loss) income to cash flows provided by operating activities:
Depreciation and amortization	71,397	61,924
Amortization of debt related costs (includes $0 and $2,994 write off of deferred financing fees)	1,916	4,926
Deferred income taxes	(4,115)	(8,072)
Share-based compensation	14,248	11,257
Gain on sale of property, plant and equipment	(588)	(6,507)
Foreign currency exchange losses (gains) on intercompany loans and other non-cash items	4,002	5,059
Changes in assets and liabilities
Accounts receivable	7,495	14,509
Inventories	(17,664)	(20,385)
Contract assets	(6,912)	(18,519)
Prepaids and other current assets	7,260	(5,559)
Accounts payable	(2,819)	26,910
Accrued expenses and other liabilities	(19,578)	(33,548)
Contract liabilities	13,051	(5,567)
Income taxes	(6,786)	3,471
Other non‑current assets and liabilities	3,875	(4,123)
Net cash provided by operating activities	54,357	36,788
Investing activities
Purchase of property, plant and equipment	(63,948)	(54,569)
Purchase of intangibles	(4,775)	(1,536)
Proceeds from sale of property, plant and equipment	2,860	13,247
Proceeds from Divestiture of Businesses	0	430
Payments to Acquire Businesses, Net of Cash Acquired	(2,811)	(10,235)
Net cash used in investing activities	(68,674)	(52,663)
Financing activities
Issuance of debt, net of deferred issuance costs	15,965	3,394
Borrowings under credit facility	230,000	46,812
Repayment of debt	(238,908)	(154,752)
Repayment of capital lease obligation	(9,273)	(5,990)
Payment for Contingent Consideration Liability, Financing Activities	(461)	(1,719)
Proceeds from issuance of common stock	341	137,605
Taxes paid related to net share settlements of share-based compensation awards	(1,248)	(7,767)
Stock repurchases	0	(230)
Cash paid for interest rate cap	(2,235)	0
Distribution to non‑controlling interest	(750)	(2,425)
Net cash (used in) provided by financing activities	(6,569)	14,928
Effect of exchange rate changes on cash	(357)	(1,000)
Change in cash and cash equivalents	(21,243)	(1,947)
Cash and cash equivalents
Beginning of period	82,365	59,254
End of period	61,122	57,307
Supplemental disclosure of cash flow information
Cash paid for taxes	8,731	4,020
Cash paid for interest	39,409	31,179
Non‑cash investing and financing activities
Noncash or Part Noncash Acquisitions, Accrued Earnout	0	1,395
Capital lease transactions	$ 11,788	$ 5,275

Unaudited Consolidated Statem_6

Unaudited Consolidated Statements of Changes in Cash Flows Unaudited Supplemental Disclosure of Cash Flow Information (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Statement of Cash Flows [Abstract]
Deferred finance costs	$ 0	$ 2,994
Cash Acquired from Acquisition	$ 2,073	$ 28

Description of the Company and

Description of the Company and Basis of Presentation	9 Months Ended
	Jun. 30, 2019
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”) was incorporated on October 7, 2013. On January 15, 2014, Evoqua Water Technologies Corp., acquired through its wholly owned entities, EWT Holdings II Corp. and EWT Holdings III Corp. (a/k/a Evoqua Water Technologies), all of the outstanding shares of Siemens Water Technologies, a group of legal entity businesses formerly owned by Siemens AG (“Siemens”). The stock purchase closed on January 15, 2014 and was effective January 16, 2014 (the “Acquisition”). The stock purchase price, net of cash received, was approximately $730,577 . On November 6, 2017, the Company completed its initial public offering (“IPO”), pursuant to which an aggregate of 27,777 shares of common stock were sold, of which 8,333 were sold by the Company and 19,444 were sold by the selling shareholders , with a par value of $ 0.01 per share. After underwriting discounts and commissions and other expenses, the Company received net proceeds from the IPO of approximately $137,605 . The Company used a portion of these proceeds to repay $104,936 of indebtedness (including accrued and unpaid interest) under EWT III’s senior secured first lien term loan facility and the remainder for general corporate purposes. The Company did not receive any proceeds from the sale of shares by the selling shareholders . On November 7, 2017, the selling shareholders sold an additional 4,167 shares of common stock as a result of the exercise in full by the underwriters of an option to purchase additional shares. On March 19, 2018, the Company completed a secondary public offering, pursuant to which 17,500 shares of common stock were sold by certain selling shareholders . On March 21, 2018, the selling shareholders sold an additional 2,625 shares of common stock as a result of the exercise in full by the underwriters of an option to purchase additional shares. The Company did not receive any proceeds from the sale of shares by the selling shareholders . 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 multi‑national corporation with operations in the United States (“U.S.”), Canada, the United Kingdom (“UK”), the Netherlands, Germany, Australia, China, and Singapore. 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 Unaudited Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“ GAAP ”). All intercompany transactions have been eliminated. Unless otherwise specified, all dollar amounts in these notes are referred to in thousands. The interim Unaudited Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such SEC rules. We believe that the disclosures made are adequate to make the information presented not misleading. We consistently applied the accounting policies described in our Annual Report on Form 10-K for the fiscal year ended September 30, 2018 , as filed with the SEC on December 11, 2018 (“ 2018 Annual Report”), in preparing these Unaudited Consolidated Financial Statements , with the exception of accounting standard updates described in Note 2, “Summary of Significant Accounting Policies.” These Unaudited Consolidated Financial Statements should be read in conjunction with the audited financial statements and the notes included in our 2018 Annual Report. Certain prior period amounts have been reclassified to conform to the current period presentation.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Jun. 30, 2019
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 Unaudited 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 Unaudited Consolidated Financial Statements and the reported amounts of revenue and expenses during the reporting period. 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 us from transactions with customers and are presented net of allowances for doubtful accounts. Allowances are estimated based on historical write‑offs and the 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. Inventories Inventories are stated at the lower of cost or market, 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 Acquisitions are recorded using the purchase 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 Unaudited 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 Other Intangible Assets Goodwill represents purchase consideration paid in a business combination that exceeds the value assigned to the net assets of acquired businesses. Other 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 to determine potential impairment annually during the fourth quarter of the 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. The quantitative impairment testing 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, we incorporate our 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 our 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 Long‑lived assets, such as property, plant, and equipment, and purchased intangibles 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 straight line method which approximates 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. Beginning in the first quarter of 2019, the Company entered into an interest rate cap to mitigate risks associated with the Company’s variable rate debt. See Note 11 , “Derivative Financial Instruments” for further details. The Company paid $2,235 as a premium for the interest rate cap, which is being amortized to interest expense over its three -year term. The Company recorded $187 and $435 of premium amortization to interest expense during the three and nine months ended June 30, 2019 , respectively. Amortization of debt issuance costs and discounts included in interest expense were $498 and $478 for the three months ended June 30, 2019 and 2018 , respectively and $1,481 and $1,932 for the nine months ended June 30, 2019 and 2018 , respectively. In November 2017, the Company wrote off $1,844 of deferred financing fees related to a $100,000 prepayment of debt, then subsequently wrote off another $1,150 of fees in December of 2017 due to refinancing its First Lien Term Loan. The Company incurred another $2,131 of fees as a result of the December refinancing. Revenue Recognition The Company adopted Topic 606, Revenue from Contracts with Customers on October 1, 2018, and recognizes sales of products and services based on the five-step analysis of transactions as provided in Topic 606 which requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for such goods or services. For sales of aftermarket parts or products with a low level of customization and engineering time, the Company recognizes revenues 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. 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, the Company recognizes revenue either over time or at a point in time. These products 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. The Company recognizes revenue over time if the product has no alternative use and the Company has an enforceable right to payment for the performance completed to date, including a normal profit margin, in the event of termination for convenience. If these two criteria are not met, revenues from these contracts will not be recognized until construction is complete. Contract revenues 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 have not been material. See Note 4, “Revenue” for further details. 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 Unaudited 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. 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 and foreign currency exchange rate risk. The Company’s objective in using interest rate derivatives is to add stability to interest expense and manage its exposure to interest rate movements. To accomplish this objective, in November 2018, the Company entered into an interest rate cap which has been designated as a cash flow hedge. 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 risk, the Company entered into a series of forward contracts designated as cash flow hedges. 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). The Company recognizes all derivatives on the balance sheet at fair value. Changes in the fair values of derivatives that are not designated as hedges are recognized in earnings. If the derivative is designated and qualifies as a hedge, depending on the nature of the hedge, changes in the fair value of the derivatives are either offset against the change in the hedged assets or liabilities through earnings or recognized in Accumulated other comprehensive income (loss), net of tax (“AOCI”) until the hedged item is recognized in earnings. 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 included the enactment date. Valuation allowances are provided against deferred tax assets when it is deemed more likely than not that some portion or all of the deferred tax asset will not be realized within a reasonable time period. We assess 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 is greater than 50% percent 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 loss, net of tax within shareholders’ equity. Revenues and expenses are translated at the weighted‑average exchange rate for the period, with the resulting translation adjustments recorded in the Unaudited Consolidated Statements of Operations . Foreign currency translation (gains) losses, mainly related to intercompany loans, which aggregated $(772) and $9,340 for the three months ended June 30, 2019 and 2018 , respectively and $4,636 and $5,652 for the nine months ended June 30, 2019 and 2018 , respectively, are primarily included in General and administrative expenses in the Unaudited Consolidated Statements of Operations . Research and Development Costs Research and development costs are expensed as incurred. The Company recorded $3,281 and $3,682 for the three months ended June 30, 2019 and 2018 , respectively and $11,384 and $12,356 for the nine months ended June 30, 2019 and 2018 , respectively. 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 fair value of restricted stock unit awards is determined using the closing price of our common stock on date of grant. 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. Treated Water Outsourcing Treated Water Outsourcing (“TWO”) is a joint venture between the Company and Nalco Water, an Ecolab company, in which the Company holds a 50% partnership interest. The Company is obligated to absorb all risk of loss up to 100% of the joint venture partner’s equity. As such, the Company fully consolidates TWO as a variable interest entity (“VIE”) under ASC 810, Consolidation. The Company has not provided additional financial support to this entity which it is not contractually required to provide, and the Company does not have the ability to use the assets of TWO to settle obligations of the Company’s other subsidiaries. The following provides a summary of TWO’s balance sheet as of June 30, 2019 and September 30, 2018 , and summarized financial information for the three and nine months ended June 30, 2019 and 2018 . June 30, September 30, Current assets (includes cash of $5,921 and $3,304) $ 6,321 $ 5,486 Property, plant and equipment 4,176 4,441 Goodwill 2,206 2,206 Other non-current assets 3 3 Total liabilities (4,106 ) (3,608 ) Three Months Ended Nine Months Ended 2019 2018 2019 2018 Total revenues $ 2,573 $ 3,020 $ 8,951 $ 12,586 Total operating expenses (2,231 ) (2,535 ) (7,267 ) (9,732 ) Income from operations $ 342 $ 485 $ 1,684 $ 2,854 Recent Accounting Pronouncements In November 2018, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2018-19, Codification Improvements to Topic 326, Financial Instruments—Credit Losses which clarifies that receivables from operating leases are accounted for using the lease guidance and not as financial instruments. ASU 2018-19 will be effective for the Company for the quarter ending December 31, 2020, with early adoptions permitted. The Company is currently assessing the impact of adoption on the Company’s Unaudited Consolidated Financial Statements . In November 2018, the FASB issued ASU 2018-18, Collaborative Arrangements (Topic 808) Clarifying the Interaction between Topic 808 and Topic 606 , which clarifies that certain transactions between collaborative arrangement participants should be accounted for as revenue under Topic 606 when the collaborative arrangement participant is a customer in the context of a unit of account. In addition, unit-of-account guidance in Topic 808 was aligned with the guidance in Topic 606 (that is, a distinct good or service) when an entity is assessing whether the collaborative arrangement or a part of the arrangement is within the scope of Topic 606. ASU 2018-18 should be applied retrospectively to the date of initial adoption of Topic 606 and is effective for the Company for the quarter ending December 31, 2020, with early adoption permitted. The Company is currently assessing the impact of adoption on the Company’s Unaudited Consolidated Financial Statements . In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Subtopic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement , which modifies the disclosure requirements on fair value measurements. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. ASU 2018-14 will be effective for the Company for the quarter ending December 31, 2020, with early adoption permitted. The Company is currently assessing the impact of adoption on the Company’s disclosures. In June 2018, the FASB issued ASU 2018‑07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. ASU No. 2018‑07 will be effective for the Company for the quarter ending December 31, 2019. The Company does not expect the impact of adoption on the Company’s Unaudited Consolidated Financial Statements to be material. In August 2017, the FASB issued ASU 2017‑12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which expands and refines hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements and also made certain targeted improvements to simplify the application of hedge accounting guidance and ease the administrative burden of hedge documentation requirements and assessing hedge effectiveness. ASU 2017‑12 will be effective for the Company for the quarter ending December 31, 2019. The Company does not expect the impact of adoption on the Company’s Unaudited Consolidated Financial Statements to be material. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326) : Measurement of Credit Losses on Financial Instruments, which requires entities to use a new forward-looking “expected loss” model that reflects expected credit losses, including credit losses related to trade receivables, and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates which generally will result in the earlier recognition of allowances for losses. ASU 2016-13 will be effective for the Company for the quarter ending December 31, 2020, with early adoption permitted. The Company does not expect the impact of adoption on the Unaudited Consolidated Financial Statements to be material. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) . ASU No. 2016-02 requires recognition of operating leases as lease assets and liabilities on the balance sheet, and disclosure of key information about leasing arrangements. ASU No. 2016-02 can be applied using a modified retrospective approach and will be effective for the Company for the quarter ending December 31, 2019, with early adoption permitted. Amendments to the standard were issued by the FASB in January, July and December 2018, and March 2019 including certain practical expedients, an amendment that provides an additional and optional transition method to adopt the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption and certain narrow-scope improvements for lessors. The Company has completed its assessment of the existing lease portfolio including performing data and policy gap reviews. The Company is evaluating system requirements, updating processes and its accounting policies in order to comply with Topic 842 and is continuing to assess the impact adoption of this guidance will have on the Company’s Unaudited Consolidated Financial Statements and related disclosures. Accounting Pronouncements Recently Adopted The Company adopted ASU 2017‑09, Scope of Modification Accounting , which amended Accounting Standards Code Topic 718 as of October 1, 2018. The FASB issued ASU 2017‑09 to reduce the cost and complexity when applying Topic 718 and standardize the practice of applying Topic 718 to financial reporting. The ASU was not developed to fundamentally change the definition of a modification, but instead to provide guidance for what changes would qualify as a modification. This adoption did not have a material impact on the Company’s Unaudited Consolidated Financial Statements . The Company adopted ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost , as of October 1, 2018. This ASU requires the disaggregation of the service cost component from other components of net periodic benefit cost, clarifies how to present the service cost component and other components of net benefit costs in the Unaudited Consolidated Statements of Operations and allows only the service cost component of net benefit costs to be eligible for capitalization. The adoption of this guidance did not have an impact on the Company’s Unaudited Consolidated Financial Statements and had minimal impact to the related disclosures. The Company adopted ASU 2016-16 , Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory , as of October 1, 2018. The purpose of this update is to improve the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. The ASU requires the tax effects of all intra-entity sales of assets other than inventory to be recognized in the period in which the transaction occurs. The changes were required to be applied by means of a cumulative-effect adjustment recorded in retained earnings as of the beginning of the year of adoption, and as such the Company recorded a net increase to opening retained earnings of $181 at October 1, 2018. This adoption did not have a material impact on the Company’s Unaudited Consolidated Financial Statements . The Company adopted ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) , as of October 1, 2018. ASU No. 2014-09 clarifies the principles for recognizing revenue when an entity either enters into a contract with customers to transfer goods or services or enters into a contract for the transfer of non-financial assets. The Company utilized the modified retrospective approach and the cumulative effect of adoption resulted in a net decrease to opening retained earnings of $1,582 which was recognized at October 1, 2018. Based on the new guidance, the Company determined that for some of these contracts in which revenue was previously recognized over a period of time, revenue instead needs to be recognized at a point in time. This change is mainly due to the nature of certain products, which in some cases have an alternative use, and the Company’s right to payment in the event of termination for convenience. This adoption did not have a material impact on the Company’s Unaudited Consolidated Financial Statements . See Note 4, “Revenue” for further details.

Acquisitions and Divestitures

Acquisitions and Divestitures	9 Months Ended
	Jun. 30, 2019
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. On May 25, 2019 , the Company acquired all of the issued and outstanding equity securities of ATG UV Technology Limited (“ATG UV”), a leading manufacturer of ultraviolet (“UV”) light disinfection systems used in a wide range of municipal, aquatics and industrial applications, for £5,500 ( $6,931 ) paid in cash at closing. The Company incurred approximately $488 in acquisition costs, which are included in General and administrative expenses. ATG UV, based in Wigan, UK, is the exclusive technology supplier to Evoqua’s ETS-UV TM product line in North America and the acquisition expands Evoqua’s reach, allowing the Company to serve customers globally. ATG UV is part of the Applied Product Technologies segment. The accounting for the acquisition has not yet been completed because the Company has not finalized the valuations of the acquired assets, assumed liabilities and identifiable intangible assets, including goodwill. The preliminary opening balance sheet for ATG UV is summarized as follows: Current assets $ 6,169 Property, plant and equipment 441 Goodwill 1,610 Intangible assets 1,550 Total assets acquired 9,770 Total liabilities assumed (2,839 ) Net assets acquired $ 6,931

Revenue

Revenue	9 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	Revenue Adoption of ASU 2014-09 “Revenue from Contracts with Customers (Topic 606)” As discussed in Note 2, “Summary of Significant Accounting Policies” the Company adopted ASU 2014-09 on October 1, 2018, using the modified retrospective approach to those contracts that were not completed or substantially complete as of October 1, 2018. Results for the reporting period beginning after October 1, 2018 are presented under Topic 606, while prior period amounts have not been adjusted and continue to be reported in accordance with the Company’s historical accounting under Topic 605. The Company has applied the standard to all open contracts at the date of initial application. The Company recorded a net decrease to opening retained earnings of $1,582 as of October 1, 2018 as a result of the cumulative impact of adopting Topic 606 representing the unfavorable impact to prior results had the over-time revenue recognition for some customer agreements, as discussed below, been applied. In addition, a $6,106 reduction of contract assets, along with an increase of $6,194 to work-in-process inventory and an increase of $1,773 to contract liabilities was recorded as a result of the adoption using the modified retrospective method. The impact to the Unaudited Consolidated Statements of Operations as a result of applying Topic 606 was higher Revenue from product sales and services and Cost of product sales and services of $1,009 and $1,264 , respectively, for the three months ended June 30, 2019 and lower Revenue from product sales and services and higher Cost of product sales and services of $756 and $131 , respectively, for the nine months ended June 30, 2019 , as compared to what those amounts would have been under the previous revenue recognition guidance. In addition, the impact on the Consolidated Balance Sheets at June 30, 2019 was lower Inventories, net of $131 as compared to what this amount would have been under the previous guidance. Also, $756 of contract assets were recognized on the consolidated balance sheet at June 30, 2019 related to this over-time 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. For all contracts with customers, the Company first identifies the contract which usually is established when the customer’s purchase order is accepted or acknowledged. Next the Company identifies the performance obligations in the contract. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. The Company then determines the transaction price in the arrangement and allocates the transaction price to each performance obligation identified in the contract. The Company’s allocation of the transaction price to the performance obligations are based on the relative standalone selling prices for the goods and services contained in a particular performance obligation. The transaction price is adjusted for the Company’s estimate of variable consideration which may include discounts if the Company would fail to meet certain performance requirements, volume discounts or early payment discounts. To estimate variable consideration, the Company utilizes historical experience and known terms. Variable consideration in contracts for the three and nine months ended June 30, 2019 was insignificant. For sales of aftermarket parts or products with a low level of customization and engineering time, the Company recognizes revenues 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 service arrangements are recognized as the services are performed. 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. In these instances, revenue is recognized using a measure of progress that applies an input method based on costs incurred in relation to total estimated costs. 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. In order for revenue to be recognized over a period of time, the product must have no alternative use and the Company must have an enforceable right to payment for the performance completed to date, including a normal profit margin, in the event of termination for convenience. If these two criteria are not met, revenues from these contracts will not be recognized until construction is complete. Revenues from construction-type contracts formerly recognized over time of approximately $1,640 and $249 were not recognized during the three and nine months ended June 30, 2019 , respectively. Instead, revenues from these contracts will be recognized when construction is complete. Contract revenues 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 have not been material. 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 Company has also elected the following practical expedients: Financing Component As the Company’s standard payment terms are less than one year, the Company has elected the practical expedient not to assess whether a contract has a significant financing component. Performance Obligations The Company elects to apply the practical expedient to exclude from this disclosure revenue related to performance obligations if the 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 $125,000 at June 30, 2019 . 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 months. 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 June 30, 2019 . 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. 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 revenues: Three Months Ended Nine Months Ended Revenue from contracts with customers recognized under Topic 606 $ 325,009 $ 934,111 Other (1) 35,334 97,862 Total $ 360,343 $ 1,031,973 (1) Other revenue relates to revenue recognized from Topic 840, Leases, mainly attributable to long term rentals. Information regarding revenues disaggregated by source of revenue and segment is as follows: Three Months Ended June 30, 2019 Nine Months Ended June 30, 2019 Integrated Solutions and Services Applied Product Technologies Total Integrated Solutions and Services Applied Product Technologies Total Revenue from capital projects $ 52,132 $ 83,390 $ 135,522 $ 152,772 $ 230,887 $ 383,659 Revenue from aftermarket 29,968 44,873 74,841 93,238 120,422 213,660 Revenue from service 143,329 6,651 149,980 416,781 17,873 434,654 Total $ 225,429 $ 134,914 $ 360,343 $ 662,791 $ 369,182 $ 1,031,973 Information regarding revenues disaggregated by geographic area is as follows: Three Months Ended Nine Months Ended United States $ 284,737 $ 823,923 Canada 20,873 58,836 Europe 26,677 71,235 Asia 23,007 62,411 Australia 5,049 15,568 Total $ 360,343 $ 1,031,973 Contract Balances The Company performs its obligations under a contract with a customer by transferring products and/or services in exchange for consideration from the customer. The Company receives payments from customers based on a billing schedule as established in its contracts. 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 our performance under the contract. The tables below provides a roll-forward of contract assets and contract liabilities balances for the periods presented: Contract Assets (a) Balance at September 30, 2018 $ 69,147 Cumulative effect of adoption of new accounting standards (6,106 ) Recognized in current period 225,341 Reclassified to accounts receivable (218,433 ) Foreign currency 69 Balance at June 30, 2019 $ 70,018 (a) Excludes receivable balances which are disclosed on the Consolidated Balance Sheets . Contract Liabilities Balance at September 30, 2018 $ 17,652 Cumulative effect of adoption of new accounting standards 1,773 Recognized in current period 214,444 Amounts in beginning balance reclassified to revenue (20,127 ) Current period amounts reclassified to revenue (181,266 ) Foreign currency (164 ) Balance at June 30, 2019 $ 32,312

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurements As of June 30, 2019 and September 30, 2018 , the fair values of cash and cash equivalents, accounts receivable and accounts payable approximate carrying values due to the short maturity of these items. The Company measures the fair value of pension plan assets and liabilities, deferred compensation 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 plan 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 plan 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 fair value 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 June 30, 2019 Assets: Pension plan Cash $ — $ 14,678 $ — $ — Government Securities 2,330 — — — Liability Driven Investment 5,167 — — — Guernsey Unit Trust 961 — — — Global Absolute Return 2,015 — — — Deferred compensation plan assets Trust Assets — 401 — — Insurance — — 17,978 — Interest rate cap — — 56 — Foreign currency forward contracts — — 102 — Liabilities: Pension plan — — (34,625 ) — Deferred compensation plan liabilities — — (20,464 ) — Long‑term debt — — (954,455 ) — Foreign currency forward contracts — — (376 ) — Earn-outs related to acquisitions — — — (2,064 ) As of September 30, 2018 Assets: Pension plan Cash $ — $ 15,821 $ — $ — Government Securities 3,161 — — — Liability Driven Investment 2,598 — — — Guernsey Unit Trust 965 — — — Global Absolute Return 2,038 — — — Deferred compensation plan assets Trust Assets — 648 — — Insurance — — 18,448 — Foreign currency forward contracts — — 345 — Liabilities: Pension plan — — (35,541 ) — Deferred compensation plan liabilities — — (21,834 ) — Long‑term debt — — (957,441 ) — Foreign currency forward contracts — — (67 ) — Earn-outs related to acquisitions — — — (1,916 ) The pension plan assets and liabilities and deferred compensation plan assets and liabilities are included in other non-current assets and other non-current liabilities at June 30, 2019 and September 30, 2018 . The Company records contingent consideration arrangements at fair value on a recurring basis and the associated balances presented as of June 30, 2019 and September 30, 2018 are earn-outs related to 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 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 Unaudited Consolidated Statements of Operations . A roll-forward of the activity in the Company’s fair value of earn-outs related to acquisitions is as follows: Current Portion (1) Long-term Portion (2) Total Balance at September 30, 2018 $ 770 $ 1,146 $ 1,916 Payments (993 ) — (993 ) Fair value increase 1,143 — 1,143 Foreign currency (2 ) — (2 ) Balance at June 30, 2019 $ 918 $ 1,146 $ 2,064 (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

Accounts Receivable	9 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Accounts receivable	Accounts Receivable Accounts receivable are summarized as follows: June 30, September 30, Accounts receivable $ 252,014 $ 258,955 Allowance for doubtful accounts (4,297 ) (4,199 ) Receivables, net $ 247,717 $ 254,756

Inventories

Inventories	9 Months Ended
	Jun. 30, 2019
Inventory Disclosure [Abstract]
Inventories	Inventories The major classes of Inventories, net are as follows: June 30, September 30, Raw materials and supplies $ 78,087 $ 69,176 Work in progress 19,934 19,461 Finished goods and products held for resale 67,012 53,786 Costs of unbilled projects 7,644 1,878 Reserves for excess and obsolete (11,657 ) (9,313 ) Inventories, net $ 161,020 $ 134,988

Property, Plant, and Equipment

Property, Plant, and Equipment	9 Months Ended
	Jun. 30, 2019
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant, and Equipment Property, plant, and equipment consists of the following: June 30, September 30, Machinery and equipment $ 452,386 $ 399,619 Land and buildings 76,571 76,459 Construction in process 66,977 60,803 595,934 536,881 Less: accumulated depreciation (254,530 ) (216,858 ) $ 341,404 $ 320,023 The Company entered into secured financing agreements that require providing a security interest in specified equipment. As of June 30, 2019 , the gross and net amounts of those assets are as follows: Gross Net Machinery and equipment $ 20,385 $ 14,946 Construction in process 7,855 7,855 $ 28,240 $ 22,801 Depreciation expense and maintenance and repairs expense for the three and nine months ended June 30, 2019 and 2018 were as follows: Three Months Ended Nine Months Ended 2019 2018 2019 2018 Depreciation expense $ 15,979 $ 14,530 $ 47,334 $ 42,518 Maintenance and repair expense 6,144 6,238 18,192 17,620

Goodwill

Goodwill	9 Months Ended
	Jun. 30, 2019
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, 2018 $ 224,370 $ 186,976 $ 411,346 Business combinations — 1,610 1,610 Measurement period adjustment (1,937 ) 63 (1,874 ) Foreign currency translation (447 ) (349 ) (796 ) Balance at June 30, 2019 $ 221,986 $ 188,300 $ 410,286 As of June 30, 2019 and September 30, 2018 , $150,218 and $147,861 , respectively, of goodwill was deductible for tax purposes.

Debt

Debt	9 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Debt	Debt Long‑term debt consists of the following: June 30, September 30, First Lien Term Facility, due December 20, 2024 $ 931,123 $ 938,230 Revolving Credit Facility — — Equipment Financing, due June 30, 2024 to May 21, 2026 26,252 11,588 Notes Payable, due August 31, 2019 to July 31, 2023 1,710 2,106 Mortgage, due June 30, 2028 1,730 1,835 Total debt 960,815 953,759 Less unamortized discount and lender fees (12,647 ) (14,129 ) Total net debt 948,168 939,630 Less current portion (12,661 ) (11,555 ) Total long‑term debt $ 935,507 $ 928,075 Term Facilities and Revolving Credit Facility On January 15, 2014, EWT Holdings III Corp. (“EWT III”), an indirect wholly-owned subsidiary of the Company, entered into a First Lien Credit Agreement and Second Lien Credit Agreement (the “Credit Agreements” or, after the prepayment and termination of the Second Lien Credit Agreement, the “First Lien Credit Agreement” or “Credit Agreement”) among EWT III, EWT Holdings II Corp., the lenders party thereto and Credit Suisse AG as administrative agent and collateral agent. The First Lien Credit Agreement provided for a seven -year term loan facility, and the Second Lien Credit Agreement provided for an eight -year term loan facility. The term loan facilities originally consisted of the “First Lien Term Loan” and “Second Lien Term Loan” in aggregate principal amounts of $505,000 and $75,000 , respectively. The First Lien Credit Agreement also made available to the Company a $75,000 revolving credit facility (the “Revolver”), which provided for a letter of credit sub-facility up to $35,000 . During the year ended September 30, 2017, certain subsidiaries of the Company entered into three amendments to the First Lien Credit Agreement, which provided for, among other things, the payoff and termination of the Second Lien Term Loan, upsizes to the First Lien Term Loan, and the upsize of the Revolver. On December 20, 2017, certain subsidiaries of the Company entered into Amendment No. 5 (the “Fifth Amendment”), among EWT III, as the borrower, certain other subsidiaries of the Company, and Credit Suisse AG, as administrative agent and collateral agent, relating to the Credit Agreement. Pursuant to the Fifth Amendment, among other things, the Existing Term Loans were refinanced with the proceeds of refinancing term loans, the maturity date was extended to December 20, 2024 from January 15, 2021 and the interest rate spreads on Term Loan borrowing were reduced to 3.00% from 3.75% . In addition, the amendment increased the revolving credit commitment and letter of credit sublimit to $125,000 and $45,000 from $95,000 and $35,000 , respectively. Borrowings under the Revolver bear interest at variable rates plus a margin. In connection with the closing of the ProAct acquisition on July 26, 2018, EWT III entered into Amendment No. 6 (the “ Sixth Amendment ”) to the First Lien Credit Agreement. Pursuant to the Sixth Amendment, among other things, EWT III borrowed an additional $150,000 in incremental term loans. The other terms of the Existing Credit Agreement, including rates, remain generally the same. At June 30, 2019 , the interest rate on borrowings was 5.44% , comprised of 2.44% LIBOR plus the 3.0% spread. As a result of the incremental borrowings, quarterly principal payments increased from $1,991 to $2,369 . Total deferred fees related to the First Lien Term Loan were $12,647 and $14,129 , net of amortization, as of June 30, 2019 and September 30, 2018 , respectively. These fees were included as a contra liability to debt on the Consolidated Balance Sheets . At June 30, 2019 and September 30, 2018 , the Company had no outstanding revolver borrowings and as a result, borrowing availability under the Revolver was $125,000 at June 30, 2019 and September 30, 2018 , reduced for outstanding letters of credit. The Company’s outstanding letters of credit under this agreement aggregated approximately $13,262 and $11,777 at June 30, 2019 and September 30, 2018 , respectively. Unused amounts, defined as total revolver capacity less outstanding letters of credit and revolver borrowings, were $111,738 and $113,223 at June 30, 2019 and September 30, 2018 , respectively. At June 30, 2019 and September 30, 2018 , the Company had additional letters of credit of $214 and $64 issued under a separate arrangement, respectively. The First Lien Credit Agreement contains limitations on incremental borrowings, is subject to leverage ratios and allows for optional prepayments. Under certain circumstances, the Company may be required to remit excess cash flows as defined based upon exceeding certain leverage ratios. The Company did not exceed such ratios during the nine months ended June 30, 2019 , does not anticipate exceeding such ratios during the year ending September 30, 2019 , and therefore does not anticipate any additional repayments during the year ending September 30, 2019 . Equipment Financing As of June 30, 2019 and September 30, 2018 , the Company had equipment financings in an aggregate outstanding amount of $26,252 and $11,588 , with interest rates ranging from 5.08% to 6.55% , and due dates ranging from June 30, 2024 to May 21, 2026 . Notes Payable As of June 30, 2019 and September 30, 2018 , the Company had notes payable in an aggregate outstanding amount of $1,710 and $2,106 , with interest rates ranging from 6.26% to 7.39% , and due dates ranging from August 31, 2019 to July 31, 2023. These notes are related to certain equipment related contracts and are secured by the underlying equipment and assignment of the related contracts. Mortgage On June 29, 2018, the Company's subsidiary MAGNETO special anodes B.V. entered into a 10 -year mortgage agreement for €1,600 ( $1,822 ) to finance a facility in the Netherlands, subject to monthly principal payments of €7 ( $8 ) at a blended interest rate of 2.4% with maturity in June 2028. The Company had $1,730 and $1,835 principal outstanding under this facility at June 30, 2019 and September 30, 2018 , respectively. Repayment Schedule Aggregate maturities of all long‑term debt, including current portion of long‑term debt and excluding capital lease obligations as of June 30, 2019 , are presented below: Fiscal Year Remainder of 2019 $ 3,168 2020 12,702 2021 12,835 2022 12,977 2023 12,860 Thereafter 906,273 Total $ 960,815

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Jun. 30, 2019
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 our senior secured credit facilities, 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. To accomplish these objectives, the Company entered into an interest rate cap, designated as a cash flow hedge, to mitigate risks associated with variable rate debt effective November 28, 2018. The LIBOR interest rate cap covers a notional amount of $600,000 of the Company’s senior secured debt, is effective for a period of three years and has a strike rate of 3.5% . Interest rate caps designated as cash flow hedges involve the receipt of stipulated amounts from a counterparty if interest rates rise above the strike rate defined in the contract. The premium paid for the interest rate cap was $2,235 and is being amortized to interest expense over its three -year term using the caplet method. The unamortized premium was $1,800 at June 30, 2019 , of which $745 is included in Prepaid and other current assets and the remaining $1,055 is included in Other non‑current assets . The Company recorded $187 and $435 of premium amortization to interest expense during the three and nine months ended June 30, 2019 , respectively. Foreign Currency Risk Management The Company’s functional currency is the U.S. dollar. By operating internationally, the Company is subject to foreign currency risk from transactions denominated in currencies other than the U.S. dollar (“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 is also subject to currency translation risk associated with converting the foreign operations’ financial statements into U.S. dollars. 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 risk, the Company entered into a series of forward contracts designated as cash flow hedges. As of June 30, 2019 , the notional amount of the forward contracts held to sell foreign currencies was $30,003 . 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 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 balance sheet at fair value and adjusts to market on a quarterly basis. The Company’s interest rate cap is 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. For a derivative that is designated as a cash flow hedge, changes in the fair value of the derivative are recognized in AOCI to the extent the derivative is effective at offsetting the changes in the cash flows being hedged until the hedged item affects earnings. To the extent there is any hedge ineffectiveness, changes in fair value relating to the ineffective portion are immediately recognized in earnings in the Unaudited Consolidated Statements of Operations . The Company recorded no hedge ineffectiveness during the three and nine months ended June 30, 2019 . The Company does not use derivative financial instruments for trading or speculative purposes. The following represents the fair value recorded for derivatives designated as cash flow hedges for the periods presented: Asset Derivatives Balance Sheet Location June 30, September 30, Interest rate cap Prepaid and other current assets 56 — Foreign currency forward contracts Prepaid and other current assets 102 282 Liability Derivative Balance Sheet Location June 30, September 30, Foreign currency forward contracts Accrued expenses and other current liabilities $ 376 $ 67 The following represents the amount of (loss) gain recognized in AOCI (net of tax) during the periods presented: Three Months Ended Nine Months Ended 2019 2018 2019 2018 Interest rate cap $ (78 ) $ — $ 56 $ — Foreign currency forward contracts (173 ) (3 ) (487 ) — Based on the fair value amounts of the Company’s cash flow hedges at June 30, 2019 , the Company expects that approximately $149 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. In addition, $745 of caplet amortization will be amortized into interest expense during the next twelve months . Derivatives Not Designated as Cash Flow Hedges The following represents the fair value recorded for derivatives not designated as cash flow hedges for the periods presented: Asset Derivative Balance Sheet Location June 30, September 30, Foreign currency forward contracts Prepaid and other current assets $ — $ 63

Product Warranties

Product Warranties	9 Months Ended
	Jun. 30, 2019
Guarantees and Product Warranties [Abstract]
Product warranties	Product Warranties 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. 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 Nine Months Ended Nine Months Ended 2019 2018 2019 2018 Balance at beginning of the period $ 8,907 $ 11,164 $ 3,360 $ 6,110 Warranty provision for sales 4,134 2,540 1,148 157 Settlement of warranty claims (4,896 ) (5,511 ) (509 ) (2,710 ) Foreign currency translation and other 119 (433 ) (258 ) (12 ) Balance at end of the period $ 8,264 $ 7,760 $ 3,741 $ 3,545

Restructuring and Related Charg

Restructuring and Related Charges	9 Months Ended
	Jun. 30, 2019
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 the wind-down of the Company’s operations in Italy, restructuring of the Company’s operations in Australia, consolidation of functional support structures on a global basis, and consolidation of the Singaporean research and development center. On October 30, 2018, the Company announced a transition from a three -segment structure to a two -segment operating model designed to better serve the needs of customers worldwide. This new structure was effective October 1, 2018 and combined the Municipal services business with the former Industrial segment into a new segment, Integrated Solutions and Services , a group entirely focused on engaging directly with end users. The former Products segment and Municipal products businesses have been combined into a new segment, Applied Product Technologies , which is focused on developing product platforms to be sold primarily through third party channels. The Company expects to incur $17 million to $22 million of cash costs over the next two fiscal years as a result of this transition, of which $6 million to $7 million are related to other non-employee related business optimizations. The table below sets forth the amounts accrued for the restructuring components and related activity: Nine Months Ended 2019 2018 Balance at beginning of the period $ 710 $ 3,542 Restructuring charges related to two-segment realignment 9,274 — Restructuring charges related to other initiatives 2,086 8,752 Write off charge and other non‑cash activity (520 ) (479) Cash payments (9,830) (11,395) Other adjustments (76) 24 Balance at end of the period $ 1,644 $ 444 The balances for accrued restructuring liabilities at June 30, 2019 and September 30, 2018 , are recorded in Accrued expenses and other liabilities on the Consolidated Balance Sheets . Restructuring charges primarily represent severance charges. The Company expects to pay the remaining amounts accrued as of June 30, 2019 during the last quarter of 2019. The table below sets forth the location of amounts recorded above on the Unaudited Consolidated Statements of Operations : Nine Months Ended 2019 2018 Cost of product sales and services $ 4,912 $ 3,086 General and administrative expense 4,929 3,830 Sales and marketing expense 891 750 Research and development expense 108 607 $ 10,840 $ 8,273 The Company continues to evaluate restructuring activities that may result in additional charges in the future.

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Jun. 30, 2019
Retirement Benefits [Abstract]
Employee benefit plans	Employee Benefit Plans The Company maintains multiple employee benefit plans. Certain of the Company’s employees in the UK were participants in a Siemens 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. 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 components of net periodic benefit cost for the plans were as follows: Three Months Ended Nine Months Ended 2019 2018 2019 2018 Service cost $ 214 $ 230 $ 648 $ 705 Interest cost 118 116 357 357 Expected return on plan assets (30 ) (30 ) (90 ) (93 ) Amortization of actuarial losses 95 75 288 230 Pension expense for defined benefit plans $ 397 $ 391 $ 1,203 $ 1,199 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 Unaudited Consolidated Statements of Operations .

Income Taxes

Income Taxes	9 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The income tax provision for interim periods is comprised of tax on ordinary income (loss) provided at the most recent projected annual effective tax rate (“PAETR”), adjusted for the tax effect of discrete items. Management estimates the PAETR each quarter based on the forecasted annual pretax income or (loss) of its U.S. and non-U.S. operations. The Company is required to reduce deferred tax assets by a valuation allowance if, based on all available evidence, it is considered more likely than not that some portion or all of the benefit of the deferred tax assets will not be realized in future periods. The Company also records the income tax impact of certain discrete, unusual or infrequently occurring items including changes in judgment about valuation allowances and effects of changes in tax laws or rates, in the interim period in which they occur. When a company maintains a valuation allowance in a particular jurisdiction, no net income tax expense or (benefit) will typically be provided on income (loss) for that jurisdiction on an annual basis. Jurisdictions with projected income that maintain a valuation allowance typically will form part of the PAETR calculation discussed above. However, jurisdictions with a projected loss for the year that maintain a valuation allowance are excluded from the PAETR calculation. Instead, the income tax for these jurisdictions is computed separately. The actual year-to-date income tax expense (benefit) is the product of the most current PAETR and the actual year-to-date pretax income (loss) adjusted for any discrete tax items. The income tax expense (benefit) for a particular quarter, except for the first quarter, is the difference between the year-to-date calculation of income tax expense (benefit) and the year-to-date calculation for the prior quarter. Items unrelated to current period ordinary income or (loss) are recognized entirely in the period identified as a discrete item of tax. Discrete items generally relate to changes in tax laws, adjustments to prior period’s actual liability determined upon filing tax returns, adjustments to previously recorded reserves for uncertain tax positions, initially recording or fully reversing valuation allowances, and excess stock-based compensation deductions. The inclusion of discrete items in a particular quarter can cause the actual effective rate for that quarter to vary significantly from the PAETR. Therefore, the actual effective income tax rate for a particular quarter can vary significantly based upon the jurisdictional mix and timing of actual earnings compared to projected annual earnings, permanent items, earnings for those jurisdictions that maintain a valuation allowance, tax associated with jurisdictions excluded from the PAETR calculation and discrete items. Annual Effective Tax Rate The PAETR, which excludes the impact of discrete items, was 38.9% and 13.0% as of the nine months ended June 30, 2019 and 2018 , respectively. For the nine months ended June 30, 2019 , the PAETR of 38.9% was higher than the U.S federal statutory rate of 21.0% primarily due to higher forecasted earnings in certain non-U.S. jurisdictions that have a higher statutory tax rate than the U.S, the U.S. valuation allowance provided on U.S. deferred tax assets as well as the impact of deferred tax liabilities related to indefinite lived intangibles. The Company continues to maintain a full valuation on U.S. federal and state net deferred tax assets (excluding the tax effects of deferred tax liabilities associated with indefinite lived intangibles) for the year ending September 30, 2019 as a result of pretax losses incurred since the Company’s inception in early 2014. The Company reported positive pre-tax earnings for the first time in 2017 and is projecting positive pre-tax earnings in 2019, however, the Company generated pre-tax losses in all other years. Management believes it is prudent to retain a valuation allowance until a more consistent pattern of earnings is established and net operating loss carryforwards begin to be utilized. Prior and Current Period Tax Expense For the three months ended June 30, 2019 , the Company recognized income tax expense of $7,959 on pretax income of $12,249 . The rate of 65% differed from the U.S. statutory rate of 21.0% principally due to lower forecasted earnings in the U.S. due to restructuring initiatives for which no tax benefit will be realized, the impact of deferred tax liabilities related to indefinite lived intangibles as well as discrete items during the period related to the adjustment process for the difference between actual tax results per tax returns filed versus those expected from the prior year tax provision. For the three months ended June 30, 2018 , the Company recognized income tax expense of $1,433 on pretax income of $2,468 . The rate of 58.1% differed from the U.S. blended statutory rate of 24.5% primarily due to lower forecasted earnings in the U.S. compared to prior quarters, and an increase in unbenefited foreign losses. Discrete items for the quarter were not material. For the nine months ended June 30, 2019 , the Company recognized an income tax benefit of $1,134 on a pretax loss of $11,559 . The rate of 9.8% differed from the statutory rate of 21.0% principally due to the benefit on an overall year-to-date loss offset by higher forecasted earnings in certain non-U.S. jurisdictions that have a higher statutory tax rate than the U.S. as well as the impact of deferred tax liabilities related to indefinite lived intangibles. For the nine months ended June 30, 2018 , the Company recognized an income tax benefit of $960 on pretax income of $10,052 . The rate of 9.6% differed from the estimated annual effective tax rate of 22.8% as a result of a discrete tax benefit of $3,641 due to the remeasurement of U.S. deferred tax liabilities associated with indefinite lived intangible assets for the reduction of the U.S. statutory rate from 35% to 21% . Other discrete items were not material. There are no amounts of unrecognized tax benefits recorded for the nine months ended June 30, 2019 and 2018 . Management does not reasonably expect any significant changes to unrecognized tax benefits within next twelve months of the reporting date. Effects of the Tax Cuts and Jobs Act New tax legislation, commonly referred to as the Tax Cuts and Jobs Act (“Tax Act”), was enacted on December 22, 2017. Certain key aspects of the new law were not effective for September 30 fiscal year companies until October 1, 2018. Significant provisions of the Tax Act include: an exemption from U.S. tax on dividends of future foreign earnings, a limitation on the current deductibility of net interest expense in excess of 30% of EBITDA determined by applying U.S. tax principles, a limitation on the use of net operating losses generated after fiscal 2018 to 80% of taxable income, an incremental tax (base erosion anti-abuse tax or “BEAT”) on excessive amounts paid to foreign related parties, and an income inclusion for foreign earnings in excess of 10% of the foreign subsidiaries tangible assets (global intangible low-taxed income or “GILTI”). The Company has elected to account for GILTI in the period in which it is incurred.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Jun. 30, 2019
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 June 30, 2019 , there were approximately 1,704 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 stockholders approved the Evoqua Water Technologies Corp. 2017 Equity Incentive Plan (or the “Equity Incentive Plan”), under which equity awards may be made in the respect of 5,100 shares of common stock of the Company. Under the Equity Incentive Plan, 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). As of June 30, 2019 , there were approximately 1,985 shares available for grants under the Equity Incentive Plan. In addition to the establishment of the Equity Incentive Plan, in connection with the IPO, the Company entered into restricted stock unit (“RSU”) agreements with each of the executive officers and certain other key members of management. Pursuant to the RSU agreements, recipients received, in the aggregate 1,197 stock-settled RSUs, the aggregate value of which equals $25,000 . The RSUs will vest and settle in full upon the second anniversary of the IPO (the “Vesting Date”), subject to the grantee’s continued employment with the Company or any of its subsidiaries through the Vesting Date; provided, however, that in the event that a Change in Control (as defined in the RSU agreements) occurs prior to the Vesting Date, the RSUs will vest and settle in full upon the date of such Change in Control, subject to the grantee’s continued employment with the Company or any of its subsidiaries through the Change in Control date. In the event that the grantee’s employment is terminated for any reason prior to the Vesting Date, the grantee will forfeit each of his or her RSUs for no consideration as of the date of such termination of employment; provided, that, if the grantee’s employment is terminated without Cause (as defined in the RSU agreement) prior to the Vesting Date, the RSUs will vest and settle in full upon the Vesting Date as though the grantee had remained employed through such date. Option awards are granted at various times during the year, vest ratably at 25% per year, and are exercisable at the time of vesting. The options granted have a ten -year contractual term. Total share-based compensation expense was $4,985 and $14,308 during the three and nine months ended June 30, 2019 , respectively, of which $4,978 and $14,248 was non-cash. Share-based compensation expense was $4,405 and $11,257 during the three and nine months ended June 30, 2018 , respectively. The unrecognized compensation expense related to stock options and restricted stock units was $10,218 and $13,002 , respectively at June 30, 2019 , and is expected to be recognized over a weighted average period of 2.7 years and 1.3 years, respectively. The Company received $341 from the exercise of stock options during the nine months ended June 30, 2019 . The remaining stock options exercised during the nine months ended June 30, 2019 were effected via a cashless net exercise. A summary of the stock option activity as of June 30, 2019 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, 2018 8,973 $ 7.57 6.9 years $ 95,864 Granted 1,110 12.73 Exercised (890 ) 5.25 Cancelled (23 ) 20.88 Forfeited (494 ) 12.24 Expired — — Outstanding at June 30, 2019 8,676 $ 8.16 6.6 years $ 60,368 Options exercisable at June 30, 2019 6,183 $ 5.66 5.6 years $ 54,922 Options vested and expected to vest at June 30, 2019 8,580 $ 8.09 6.5 years $ 60,221 The total intrinsic value of options exercised (which is the amount by which the stock price exceeded the exercise price of the options on the date of exercise) during the nine months ended June 30, 2019 was $4,608 . A summary of the status of the Company's non-vested stock options as of and for the nine months ended June 30, 2019 is presented below. (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Nonvested at beginning of period 3,335 $ 4.11 Granted 1,110 3.87 Vested (1,458 ) 2.62 Forfeited (494 ) 4.31 Nonvested at end of period 2,493 $ 4.87 The total fair value of options vested during the nine months ended June 30, 2019 , was $3,819 . Restricted Stock Units The following is a summary of the RSU activity for the nine months ended June 30, 2019 . (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Outstanding at September 30, 2018 1,213 $ 20.88 Granted 880 12.68 Vested (24 ) 20.75 Forfeited (60 ) 16.58 Outstanding at June 30, 2019 2,009 $ 17.42 Vested and expected to vest at June 30, 2019 1,914 $ 17.50 Employee Stock Purchase Plan Effective October 1, 2018, the Company implemented an employee stock purchase plan (“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 day of the applicable offering period or on the last business day of a six-month purchase period within the offering period. These purchases will be offered twice throughout fiscal 2019, and will be paid by employees through payroll deductions over the respective six month purchase period, at which point the stock will be 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 nine months ended June 30, 2019 , the Company incurred compensation expense of $293 , 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. On April 1, 2019, 46 shares were issued under the ESPP plan.

Concentration of Credit Risk

Concentration of Credit Risk	9 Months Ended
	Jun. 30, 2019
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 are 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 June 30, 2019 and September 30, 2018 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 three and nine months ended June 30, 2019 and 2018 , no customer accounted for more than 10% of net sales or net accounts receivable. The Company operates predominantly in eight 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. Sales to unaffiliated customers are based on the Company locations that maintain the customer relationship and transacts the external sale.

Related_Party Transactions

Related‑Party Transactions	9 Months Ended
	Jun. 30, 2019
Related Party Transactions [Abstract]
Related‑Party Transactions	Related‑Party Transactions Transactions with Investors The Company historically paid an advisory fee per quarter to AEA Investors LP (“AEA”), the private equity firm and the Company’s ultimate majority shareholder pursuant to a management agreement. Upon the IPO, the management agreement terminated and the Company stopped paying these fees to AEA and as a result, paid no fee during the three and nine months ended June 30, 2019 and only paid $333 during the nine months ended June 30, 2018 . In addition, the Company reimbursed AEA for normal and customary expenses incurred by AEA on behalf of the Company. The Company incurred expenses, excluding advisory fees, of $18 and $43 in the nine months ended June 30, 2019 and 2018 , respectively. The Company owed no amounts to AEA at June 30, 2019 and September 30, 2018 .

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Leases The Company occupies certain facilities and operates certain equipment and vehicles under non‑cancelable lease arrangements. Lease agreements may contain lease escalation clauses and purchase and renewal options. The Company recognizes scheduled lease escalation clauses over the course of the applicable lease term on a straight-line basis in the Unaudited Consolidated Statements of Operations . Total rent expense was $5,222 and $4,091 for the three months ended June 30, 2019 and 2018 , respectively, and $16,138 and $13,843 for the nine months ended June 30, 2019 and 2018 , respectively. Future minimum aggregate rental payments under non-cancelable operating leases are as follows: Fiscal Year Remainder of 2019 $ 4,287 2020 15,409 2021 11,761 2022 7,810 2023 5,499 Thereafter 11,446 Total $ 56,212 Capital Leases The gross and net carrying values of the equipment under capital leases as of June 30, 2019 and September 30, 2018 was as follows: June 30, September 30, Gross carrying amount $ 60,923 $ 52,314 Net carrying amount 33,372 31,116 The following is a schedule showing the future minimum lease payments under capital leases by years and the present value of the minimum lease payments as of June 30, 2019 . Fiscal Year Remainder of 2019 $ 4,229 2020 12,303 2021 9,031 2022 6,415 2023 4,112 Thereafter 4,466 Total 40,556 Less amount representing interest (at rates ranging from 1.71% to 9.71%) 8,402 Present value of net minimum capital lease payments 32,154 Less current installments of obligations under capital leases 12,830 Obligations under capital leases, excluding current installments $ 19,324 The current installments of obligations under capital leases are included in Accrued expenses and other liabilities. Obligations under capital leases, excluding current installments, are included in Other non-current liabilities. The Company is a lessor to multiple parties. The Company purchases equipment through internal funding or bank debt equal to the fair market value of the equipment. The equipment is then leased to customers for periods ranging from five to twenty years . As of June 30, 2019 , future minimum lease payments receivable under operating leases are as follows: Fiscal year Remainder of 2019 $ 746 2020 6,357 2021 5,385 2022 5,444 2023 4,462 Thereafter 61,407 Future minimum lease payments $ 83,801 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. As of June 30, 2019 and September 30, 2018 the Company had letters of credit totaling $13,262 and $11,777 , respectively, and surety bonds totaling $138,138 and $123,427 respectively, outstanding under the Company’s credit arrangements. The longest maturity date of the letters of credit and surety bonds in effect as of June 30, 2019 was March 26, 2029 . Additionally, as of June 30, 2019 and September 30, 2018 , the Company had letters of credit totaling $0 and $857 , respectively, and surety bonds totaling $1,241 and $2,469 , respectively, outstanding under the Company’s prior arrangement with Siemens. Litigation From time to time, the Company is subject to various claims, charges and litigation matters that arise in the ordinary course of business. The Company believes these actions are a normal incident of the nature and kind of business in which the Company is engaged. While it is not feasible to predict the outcome of these matters with certainty, the Company does not believe that any asserted or unasserted legal claims or proceedings, individually or in the aggregate, will have a material adverse effect on its business, financial condition, results of operations or prospects.

Accrued Expenses and Other Liab

Accrued Expenses and Other Liabilities	9 Months Ended
	Jun. 30, 2019
Payables and Accruals [Abstract]
Accrued Expenses and Other Liabilities	Accrued Expenses and Other Liabilities Accrued expenses and other liabilities consisted of the following: June 30, September 30, Salaries, wages and other benefits $ 27,397 $ 34,688 Obligation under capital leases 12,830 12,236 Third party commissions 10,262 5,097 Taxes, other than income 5,571 11,561 Insurance liabilities 4,705 5,005 Provisions for litigation 1,856 1,137 Severance payments 1,644 710 Earn-outs related to acquisitions 918 770 Other 24,090 26,468 $ 89,273 $ 97,672

Business Segments

Business Segments	9 Months Ended
	Jun. 30, 2019
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. During the first quarter of 2019, the Company implemented changes to its organizational and management structure that resulted in changes to our reportable operating segments for financial reporting purposes. Through the fiscal year ended September 30, 2018, the Company had three reportable operating segments: Industrial, Municipal and Products. Changes in the management reporting structure during the first quarter of 2019 required an assessment to be conducted in accordance with ASC Topic 280, Segment Reporting, to determine the Company’s reportable operating segments. As a result of this assessment, the Company now has two reportable operating segments, Integrated Solutions and Services and Applied Product Technologies . Prior period information has been revised to reflect this new segment structure. 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. The Company evaluates its business segments’ operating results based on earnings before interest, taxes, depreciation and amortization, and certain other charges that are specific to the activities of the respective segments. Corporate activities include general corporate expenses, elimination of intersegment transactions, interest income and expense and certain other charges. Certain other charges 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, certain integration costs and recognition of backlog intangible assets recorded in purchase accounting) and share-based compensation charges. Since certain administrative and other operating expenses and other items 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. Three Months Ended Nine Months Ended 2019 2018 2019 2018 Total sales Integrated Solutions and Services $ 227,815 $ 211,238 $ 669,031 $ 613,503 Applied Product Technologies 158,526 152,835 437,196 425,388 Total sales 386,341 364,073 1,106,227 1,038,891 Intersegment sales Integrated Solutions and Services 2,386 1,902 6,240 7,786 Applied Product Technologies 23,612 19,696 68,014 57,890 Total intersegment sales 25,998 21,598 74,254 65,676 Sales to external customers Integrated Solutions and Services 225,429 209,336 662,791 605,717 Applied Product Technologies 134,914 133,139 369,182 367,498 Total sales 360,343 342,475 1,031,973 973,215 Earnings before interest, taxes, depreciation and amortization (EBITDA) Integrated Solutions and Services 51,380 41,473 144,589 132,785 Applied Product Technologies 26,874 32,201 51,504 72,332 Corporate (27,018 ) (37,274 ) (92,496 ) (92,718 ) Total EBITDA 51,236 36,400 103,597 112,399 Depreciation and amortization Integrated Solutions and Services 14,035 12,253 42,307 34,875 Applied Product Technologies 4,350 4,146 13,142 12,040 Corporate 5,760 5,163 15,948 15,009 Total depreciation and amortization 24,145 21,562 71,397 61,924 Operating profit (loss) Integrated Solutions and Services 37,345 29,220 102,282 97,910 Applied Product Technologies 22,524 28,055 38,362 60,292 Corporate (32,778 ) (42,437 ) (108,444 ) (107,727 ) Total operating profit 27,091 14,838 32,200 50,475 Interest expense (14,842 ) (12,370 ) (43,759 ) (40,423 ) Income (loss) before income taxes 12,249 2,468 (11,559 ) 10,052 Income tax (expense) benefit (7,959 ) (1,433 ) 1,134 960 Net income (loss) $ 4,290 $ 1,035 $ (10,425 ) $ 11,012 Capital expenditures Integrated Solutions and Services $ 19,646 $ 15,672 $ 53,303 $ 37,595 Applied Product Technologies 1,720 4,688 5,988 8,563 Corporate 1,900 2,539 4,657 8,411 Total capital expenditures $ 23,266 $ 22,899 $ 63,948 $ 54,569 June 30, September 30, Assets Integrated Solutions and Services $ 745,280 $ 711,622 Applied Product Technologies 666,206 677,993 Corporate 259,969 274,002 Total assets $ 1,671,455 $ 1,663,617 Goodwill Integrated Solutions and Services $ 221,986 $ 224,370 Applied Product Technologies 188,300 186,976 Total goodwill $ 410,286 $ 411,346

Earnings per Share

Earnings per Share	9 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Earnings per share	Earnings Per Share The following table sets forth the computation of basic and diluted earnings (loss) from continuing operations per common share (in thousands, except per share amounts): Three Months Ended Nine Months Ended 2019 2018 2019 2018 Numerator: Numerator for basic and diluted loss per common share—Net income (loss) attributable to Evoqua Water Technologies Corp. $ 4,135 $ 793 $ (11,211 ) $ 9,585 Denominator: Denominator for basic net income (loss) per common share—weighted average shares 114,653 113,842 114,653 113,842 Effect of dilutive securities: Share‑based compensation 4,781 5,205 — 6,094 Denominator for diluted net income (loss) per common share—adjusted weighted average shares 119,434 119,047 114,653 119,936 Basic earnings (loss) attributable to Evoqua Water Technologies Corp. per common share $ 0.04 $ 0.01 $ (0.10 ) $ 0.08 Diluted earnings (loss) attributable to Evoqua Water Technologies Corp. per common share $ 0.03 $ 0.01 $ (0.10 ) $ 0.08 Since the Company was in a net loss position for the nine months ended June 30, 2019 , there was no difference between the number of shares used to calculate basic and diluted loss per share. Because of their anti-dilutive effect, 4,358 common share equivalents, comprised of employee stock options, have been excluded from the diluted EPS calculation for the nine months ended June 30, 2019 .

Subsequent Events

Subsequent Events	9 Months Ended
	Jun. 30, 2019
Subsequent Events [Abstract]
Subsequent Events [Text Block]	Subsequent Events On July 5, 2019, the Company completed an equipment financing for $19.5 million related to a large outsourced water project. The financing includes an imputed interest rate of 8.263% and fifteen year amortization with a bullet payment at year ten.

Description of the Company an_2

Description of the Company and Basis of Presentation (Policies)	9 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Acquisitions	Acquisitions Acquisitions are recorded using the purchase 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 Unaudited Consolidated Statements of Operations . Acquisition-related expenses and restructuring costs, if any, are recognized separately from the business combination and are expensed as incurred.
Impairment or disposal of long-lived assets	Impairment of Long‑Lived Assets Long‑lived assets, such as property, plant, and equipment, and purchased intangibles 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.
Fiscal year	Fiscal Year The Company’s fiscal year ends on September 30.
Earnings 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.
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 fair value of restricted stock unit awards is determined using the closing price of our common stock on date of grant. 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.
Research and development cost	Research and Development Costs Research and development costs are expensed as incurred.
Revenue recognition	Revenue Recognition The Company adopted Topic 606, Revenue from Contracts with Customers on October 1, 2018, and recognizes sales of products and services based on the five-step analysis of transactions as provided in Topic 606 which requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for such goods or services. For sales of aftermarket parts or products with a low level of customization and engineering time, the Company recognizes revenues 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. 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, the Company recognizes revenue either over time or at a point in time. These products 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. The Company recognizes revenue over time if the product has no alternative use and the Company has an enforceable right to payment for the performance completed to date, including a normal profit margin, in the event of termination for convenience. If these two criteria are not met, revenues from these contracts will not be recognized until construction is complete. Contract revenues 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 have not been material.
Basis of presentation	Basis of Presentation The accompanying Unaudited Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“ GAAP ”). All intercompany transactions have been eliminated. Unless otherwise specified, all dollar amounts in these notes are referred to in thousands. The interim Unaudited Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such SEC rules. We believe that the disclosures made are adequate to make the information presented not misleading. We consistently applied the accounting policies described in our Annual Report on Form 10-K for the fiscal year ended September 30, 2018 , as filed with the SEC on December 11, 2018 (“ 2018 Annual Report”), in preparing these Unaudited Consolidated Financial Statements , with the exception of accounting standard updates described in Note 2, “Summary of Significant Accounting Policies.” These Unaudited Consolidated Financial Statements should be read in conjunction with the audited financial statements and the notes included in our 2018 Annual Report.
Standard product warranty	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 Unaudited 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.
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 and foreign currency exchange rate risk. The Company’s objective in using interest rate derivatives is to add stability to interest expense and manage its exposure to interest rate movements. To accomplish this objective, in November 2018, the Company entered into an interest rate cap which has been designated as a cash flow hedge. 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 risk, the Company entered into a series of forward contracts designated as cash flow hedges. 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). The Company recognizes all derivatives on the balance sheet at fair value. Changes in the fair values of derivatives that are not designated as hedges are recognized in earnings. If the derivative is designated and qualifies as a hedge, depending on the nature of the hedge, changes in the fair value of the derivatives are either offset against the change in the hedged assets or liabilities through earnings or recognized in Accumulated other comprehensive income (loss), net of tax (“AOCI”) until the hedged item is recognized in 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 included the enactment date. Valuation allowances are provided against deferred tax assets when it is deemed more likely than not that some portion or all of the deferred tax asset will not be realized within a reasonable time period. We assess 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 is greater than 50% percent of being realized. Uncertain tax positions are reviewed each balance sheet date.
Foreign currency translations 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 loss, net of tax within shareholders’ equity. Revenues and expenses are translated at the weighted‑average exchange rate for the period, with the resulting translation adjustments recorded in the Unaudited Consolidated Statements of Operations .
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 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	Recent Accounting Pronouncements In November 2018, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2018-19, Codification Improvements to Topic 326, Financial Instruments—Credit Losses which clarifies that receivables from operating leases are accounted for using the lease guidance and not as financial instruments. ASU 2018-19 will be effective for the Company for the quarter ending December 31, 2020, with early adoptions permitted. The Company is currently assessing the impact of adoption on the Company’s Unaudited Consolidated Financial Statements . In November 2018, the FASB issued ASU 2018-18, Collaborative Arrangements (Topic 808) Clarifying the Interaction between Topic 808 and Topic 606 , which clarifies that certain transactions between collaborative arrangement participants should be accounted for as revenue under Topic 606 when the collaborative arrangement participant is a customer in the context of a unit of account. In addition, unit-of-account guidance in Topic 808 was aligned with the guidance in Topic 606 (that is, a distinct good or service) when an entity is assessing whether the collaborative arrangement or a part of the arrangement is within the scope of Topic 606. ASU 2018-18 should be applied retrospectively to the date of initial adoption of Topic 606 and is effective for the Company for the quarter ending December 31, 2020, with early adoption permitted. The Company is currently assessing the impact of adoption on the Company’s Unaudited Consolidated Financial Statements . In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Subtopic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement , which modifies the disclosure requirements on fair value measurements. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. ASU 2018-14 will be effective for the Company for the quarter ending December 31, 2020, with early adoption permitted. The Company is currently assessing the impact of adoption on the Company’s disclosures. In June 2018, the FASB issued ASU 2018‑07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. ASU No. 2018‑07 will be effective for the Company for the quarter ending December 31, 2019. The Company does not expect the impact of adoption on the Company’s Unaudited Consolidated Financial Statements to be material. In August 2017, the FASB issued ASU 2017‑12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which expands and refines hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements and also made certain targeted improvements to simplify the application of hedge accounting guidance and ease the administrative burden of hedge documentation requirements and assessing hedge effectiveness. ASU 2017‑12 will be effective for the Company for the quarter ending December 31, 2019. The Company does not expect the impact of adoption on the Company’s Unaudited Consolidated Financial Statements to be material. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326) : Measurement of Credit Losses on Financial Instruments, which requires entities to use a new forward-looking “expected loss” model that reflects expected credit losses, including credit losses related to trade receivables, and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates which generally will result in the earlier recognition of allowances for losses. ASU 2016-13 will be effective for the Company for the quarter ending December 31, 2020, with early adoption permitted. The Company does not expect the impact of adoption on the Unaudited Consolidated Financial Statements to be material. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) . ASU No. 2016-02 requires recognition of operating leases as lease assets and liabilities on the balance sheet, and disclosure of key information about leasing arrangements. ASU No. 2016-02 can be applied using a modified retrospective approach and will be effective for the Company for the quarter ending December 31, 2019, with early adoption permitted. Amendments to the standard were issued by the FASB in January, July and December 2018, and March 2019 including certain practical expedients, an amendment that provides an additional and optional transition method to adopt the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption and certain narrow-scope improvements for lessors. The Company has completed its assessment of the existing lease portfolio including performing data and policy gap reviews. The Company is evaluating system requirements, updating processes and its accounting policies in order to comply with Topic 842 and is continuing to assess the impact adoption of this guidance will have on the Company’s Unaudited Consolidated Financial Statements and related disclosures. Accounting Pronouncements Recently Adopted The Company adopted ASU 2017‑09, Scope of Modification Accounting , which amended Accounting Standards Code Topic 718 as of October 1, 2018. The FASB issued ASU 2017‑09 to reduce the cost and complexity when applying Topic 718 and standardize the practice of applying Topic 718 to financial reporting. The ASU was not developed to fundamentally change the definition of a modification, but instead to provide guidance for what changes would qualify as a modification. This adoption did not have a material impact on the Company’s Unaudited Consolidated Financial Statements . The Company adopted ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost , as of October 1, 2018. This ASU requires the disaggregation of the service cost component from other components of net periodic benefit cost, clarifies how to present the service cost component and other components of net benefit costs in the Unaudited Consolidated Statements of Operations and allows only the service cost component of net benefit costs to be eligible for capitalization. The adoption of this guidance did not have an impact on the Company’s Unaudited Consolidated Financial Statements and had minimal impact to the related disclosures. The Company adopted ASU 2016-16 , Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory , as of October 1, 2018. The purpose of this update is to improve the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. The ASU requires the tax effects of all intra-entity sales of assets other than inventory to be recognized in the period in which the transaction occurs. The changes were required to be applied by means of a cumulative-effect adjustment recorded in retained earnings as of the beginning of the year of adoption, and as such the Company recorded a net increase to opening retained earnings of $181 at October 1, 2018. This adoption did not have a material impact on the Company’s Unaudited Consolidated Financial Statements . The Company adopted ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) , as of October 1, 2018. ASU No. 2014-09 clarifies the principles for recognizing revenue when an entity either enters into a contract with customers to transfer goods or services or enters into a contract for the transfer of non-financial assets. The Company utilized the modified retrospective approach and the cumulative effect of adoption resulted in a net decrease to opening retained earnings of $1,582 which was recognized at October 1, 2018. Based on the new guidance, the Company determined that for some of these contracts in which revenue was previously recognized over a period of time, revenue instead needs to be recognized at a point in time. This change is mainly due to the nature of certain products, which in some cases have an alternative use, and the Company’s right to payment in the event of termination for convenience. This adoption did not have a material impact on the Company’s Unaudited Consolidated Financial Statements . See Note 4, “Revenue” for further details.
Use of estimates	Use of Estimates The Unaudited 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 Unaudited Consolidated Financial Statements and the reported amounts of revenue and expenses during the reporting period. 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.
Receivables	Accounts Receivable Receivables are primarily comprised of uncollected amounts owed to us from transactions with customers and are presented net of allowances for doubtful accounts. Allowances are estimated based on historical write‑offs and the 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.
Inventories	Inventories Inventories are stated at the lower of cost or market, 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.
Goodwill and other intangible assets	Goodwill and Other Intangible Assets Goodwill represents purchase consideration paid in a business combination that exceeds the value assigned to the net assets of acquired businesses. Other 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 to determine potential impairment annually during the fourth quarter of the 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. The quantitative impairment testing 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, we incorporate our 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 our current budget and long‑range plans, including anticipated change in market conditions, industry trend, growth rates and planned capital expenditures, among other considerations.
Debt issuance costs	Debt Issuance Costs and Debt Discounts Debt issuance costs are capitalized and amortized over the contractual term of the underlying debt using the straight line method which approximates 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.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Jun. 30, 2019
Accounting Policies [Abstract]
Schedule of Variable Interest Entities [Table Text Block]	The following provides a summary of TWO’s balance sheet as of June 30, 2019 and September 30, 2018 , and summarized financial information for the three and nine months ended June 30, 2019 and 2018 . June 30, September 30, Current assets (includes cash of $5,921 and $3,304) $ 6,321 $ 5,486 Property, plant and equipment 4,176 4,441 Goodwill 2,206 2,206 Other non-current assets 3 3 Total liabilities (4,106 ) (3,608 ) Three Months Ended Nine Months Ended 2019 2018 2019 2018 Total revenues $ 2,573 $ 3,020 $ 8,951 $ 12,586 Total operating expenses (2,231 ) (2,535 ) (7,267 ) (9,732 ) Income from operations $ 342 $ 485 $ 1,684 $ 2,854
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: June 30, September 30, Machinery and equipment $ 452,386 $ 399,619 Land and buildings 76,571 76,459 Construction in process 66,977 60,803 595,934 536,881 Less: accumulated depreciation (254,530 ) (216,858 ) $ 341,404 $ 320,023 Depreciation expense and maintenance and repairs expense for the three and nine months ended June 30, 2019 and 2018 were as follows: Three Months Ended Nine Months Ended 2019 2018 2019 2018 Depreciation expense $ 15,979 $ 14,530 $ 47,334 $ 42,518 Maintenance and repair expense 6,144 6,238 18,192 17,620

Acquisitions and Divestitures (

Acquisitions and Divestitures (Tables)	9 Months Ended
	Jun. 30, 2019
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	The preliminary opening balance sheet for ATG UV is summarized as follows: Current assets $ 6,169 Property, plant and equipment 441 Goodwill 1,610 Intangible assets 1,550 Total assets acquired 9,770 Total liabilities assumed (2,839 ) Net assets acquired $ 6,931

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	Information regarding the source of revenues: Three Months Ended Nine Months Ended Revenue from contracts with customers recognized under Topic 606 $ 325,009 $ 934,111 Other (1) 35,334 97,862 Total $ 360,343 $ 1,031,973 (1) Other revenue relates to revenue recognized from Topic 840, Leases, mainly attributable to long term rentals. Information regarding revenues disaggregated by source of revenue and segment is as follows: Three Months Ended June 30, 2019 Nine Months Ended June 30, 2019 Integrated Solutions and Services Applied Product Technologies Total Integrated Solutions and Services Applied Product Technologies Total Revenue from capital projects $ 52,132 $ 83,390 $ 135,522 $ 152,772 $ 230,887 $ 383,659 Revenue from aftermarket 29,968 44,873 74,841 93,238 120,422 213,660 Revenue from service 143,329 6,651 149,980 416,781 17,873 434,654 Total $ 225,429 $ 134,914 $ 360,343 $ 662,791 $ 369,182 $ 1,031,973 Information regarding revenues disaggregated by geographic area is as follows: Three Months Ended Nine Months Ended United States $ 284,737 $ 823,923 Canada 20,873 58,836 Europe 26,677 71,235 Asia 23,007 62,411 Australia 5,049 15,568 Total $ 360,343 $ 1,031,973
Contract with Customer, Asset and Liability	The tables below provides a roll-forward of contract assets and contract liabilities balances for the periods presented: Contract Assets (a) Balance at September 30, 2018 $ 69,147 Cumulative effect of adoption of new accounting standards (6,106 ) Recognized in current period 225,341 Reclassified to accounts receivable (218,433 ) Foreign currency 69 Balance at June 30, 2019 $ 70,018 (a) Excludes receivable balances which are disclosed on the Consolidated Balance Sheets . Contract Liabilities Balance at September 30, 2018 $ 17,652 Cumulative effect of adoption of new accounting standards 1,773 Recognized in current period 214,444 Amounts in beginning balance reclassified to revenue (20,127 ) Current period amounts reclassified to revenue (181,266 ) Foreign currency (164 ) Balance at June 30, 2019 $ 32,312

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	A roll-forward of the activity in the Company’s fair value of earn-outs related to acquisitions is as follows: Current Portion (1) Long-term Portion (2) Total Balance at September 30, 2018 $ 770 $ 1,146 $ 1,916 Payments (993 ) — (993 ) Fair value increase 1,143 — 1,143 Foreign currency (2 ) — (2 ) Balance at June 30, 2019 $ 918 $ 1,146 $ 2,064 (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 .
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 plan 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 plan 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 fair value 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 June 30, 2019 Assets: Pension plan Cash $ — $ 14,678 $ — $ — Government Securities 2,330 — — — Liability Driven Investment 5,167 — — — Guernsey Unit Trust 961 — — — Global Absolute Return 2,015 — — — Deferred compensation plan assets Trust Assets — 401 — — Insurance — — 17,978 — Interest rate cap — — 56 — Foreign currency forward contracts — — 102 — Liabilities: Pension plan — — (34,625 ) — Deferred compensation plan liabilities — — (20,464 ) — Long‑term debt — — (954,455 ) — Foreign currency forward contracts — — (376 ) — Earn-outs related to acquisitions — — — (2,064 ) As of September 30, 2018 Assets: Pension plan Cash $ — $ 15,821 $ — $ — Government Securities 3,161 — — — Liability Driven Investment 2,598 — — — Guernsey Unit Trust 965 — — — Global Absolute Return 2,038 — — — Deferred compensation plan assets Trust Assets — 648 — — Insurance — — 18,448 — Foreign currency forward contracts — — 345 — Liabilities: Pension plan — — (35,541 ) — Deferred compensation plan liabilities — — (21,834 ) — Long‑term debt — — (957,441 ) — Foreign currency forward contracts — — (67 ) — Earn-outs related to acquisitions — — — (1,916 )

Accounts Receivable (Tables)

Accounts Receivable (Tables)	9 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Schedule of accounts receivable	Accounts receivable are summarized as follows: June 30, September 30, Accounts receivable $ 252,014 $ 258,955 Allowance for doubtful accounts (4,297 ) (4,199 ) Receivables, net $ 247,717 $ 254,756

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Jun. 30, 2019
Inventory Disclosure [Abstract]
Schedule of Inventory	The major classes of Inventories, net are as follows: June 30, September 30, Raw materials and supplies $ 78,087 $ 69,176 Work in progress 19,934 19,461 Finished goods and products held for resale 67,012 53,786 Costs of unbilled projects 7,644 1,878 Reserves for excess and obsolete (11,657 ) (9,313 ) Inventories, net $ 161,020 $ 134,988

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	9 Months Ended
	Jun. 30, 2019
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: June 30, September 30, Machinery and equipment $ 452,386 $ 399,619 Land and buildings 76,571 76,459 Construction in process 66,977 60,803 595,934 536,881 Less: accumulated depreciation (254,530 ) (216,858 ) $ 341,404 $ 320,023 Depreciation expense and maintenance and repairs expense for the three and nine months ended June 30, 2019 and 2018 were as follows: Three Months Ended Nine Months Ended 2019 2018 2019 2018 Depreciation expense $ 15,979 $ 14,530 $ 47,334 $ 42,518 Maintenance and repair expense 6,144 6,238 18,192 17,620
Schedule of Financial Instruments Owned and Pledged as Collateral	Gross Net Machinery and equipment $ 20,385 $ 14,946 Construction in process 7,855 7,855 $ 28,240 $ 22,801

Goodwill (Tables)

Goodwill (Tables)	9 Months Ended
	Jun. 30, 2019
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, 2018 $ 224,370 $ 186,976 $ 411,346 Business combinations — 1,610 1,610 Measurement period adjustment (1,937 ) 63 (1,874 ) Foreign currency translation (447 ) (349 ) (796 ) Balance at June 30, 2019 $ 221,986 $ 188,300 $ 410,286

Debt (Tables)

Debt (Tables)	9 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Long‑term debt consists of the following: June 30, September 30, First Lien Term Facility, due December 20, 2024 $ 931,123 $ 938,230 Revolving Credit Facility — — Equipment Financing, due June 30, 2024 to May 21, 2026 26,252 11,588 Notes Payable, due August 31, 2019 to July 31, 2023 1,710 2,106 Mortgage, due June 30, 2028 1,730 1,835 Total debt 960,815 953,759 Less unamortized discount and lender fees (12,647 ) (14,129 ) Total net debt 948,168 939,630 Less current portion (12,661 ) (11,555 ) Total long‑term debt $ 935,507 $ 928,075
Schedule of Aggregate Maturities of Long-term Debt	Aggregate maturities of all long‑term debt, including current portion of long‑term debt and excluding capital lease obligations as of June 30, 2019 , are presented below: Fiscal Year Remainder of 2019 $ 3,168 2020 12,702 2021 12,835 2022 12,977 2023 12,860 Thereafter 906,273 Total $ 960,815

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	9 Months Ended
	Jun. 30, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]	The following represents the amount of (loss) gain recognized in AOCI (net of tax) during the periods presented: Three Months Ended Nine Months Ended 2019 2018 2019 2018 Interest rate cap $ (78 ) $ — $ 56 $ — Foreign currency forward contracts (173 ) (3 ) (487 ) —
Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [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 designated as cash flow hedges for the periods presented: Asset Derivatives Balance Sheet Location June 30, September 30, Interest rate cap Prepaid and other current assets 56 — Foreign currency forward contracts Prepaid and other current assets 102 282 Liability Derivative Balance Sheet Location June 30, September 30, Foreign currency forward contracts Accrued expenses and other current liabilities $ 376 $ 67
Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [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 cash flow hedges for the periods presented: Asset Derivative Balance Sheet Location June 30, September 30, Foreign currency forward contracts Prepaid and other current assets $ — $ 63

Product Warranties (Tables)

Product Warranties (Tables)	9 Months Ended
	Jun. 30, 2019
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 Nine Months Ended Nine Months Ended 2019 2018 2019 2018 Balance at beginning of the period $ 8,907 $ 11,164 $ 3,360 $ 6,110 Warranty provision for sales 4,134 2,540 1,148 157 Settlement of warranty claims (4,896 ) (5,511 ) (509 ) (2,710 ) Foreign currency translation and other 119 (433 ) (258 ) (12 ) Balance at end of the period $ 8,264 $ 7,760 $ 3,741 $ 3,545

Restructuring and Related Cha_2

Restructuring and Related Charges (Tables)	9 Months Ended
	Jun. 30, 2019
Restructuring and Related Activities [Abstract]
Schedule of restructuring components	The table below sets forth the location of amounts recorded above on the Unaudited Consolidated Statements of Operations : Nine Months Ended 2019 2018 Cost of product sales and services $ 4,912 $ 3,086 General and administrative expense 4,929 3,830 Sales and marketing expense 891 750 Research and development expense 108 607 $ 10,840 $ 8,273 Nine Months Ended 2019 2018 Balance at beginning of the period $ 710 $ 3,542 Restructuring charges related to two-segment realignment 9,274 — Restructuring charges related to other initiatives 2,086 8,752 Write off charge and other non‑cash activity (520 ) (479) Cash payments (9,830) (11,395) Other adjustments (76) 24 Balance at end of the period $ 1,644 $ 444

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Jun. 30, 2019
Retirement Benefits [Abstract]
Schedule of net benefit costs	for the plans were as follows: Three Months Ended Nine Months Ended 2019 2018 2019 2018 Service cost $ 214 $ 230 $ 648 $ 705 Interest cost 118 116 357 357 Expected return on plan assets (30 ) (30 ) (90 ) (93 ) Amortization of actuarial losses 95 75 288 230 Pension expense for defined benefit plans $ 397 $ 391 $ 1,203 $ 1,199

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Jun. 30, 2019
Share-based Payment Arrangement [Abstract]
Stock options, activity	A summary of the stock option activity as of June 30, 2019 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, 2018 8,973 $ 7.57 6.9 years $ 95,864 Granted 1,110 12.73 Exercised (890 ) 5.25 Cancelled (23 ) 20.88 Forfeited (494 ) 12.24 Expired — — Outstanding at June 30, 2019 8,676 $ 8.16 6.6 years $ 60,368 Options exercisable at June 30, 2019 6,183 $ 5.66 5.6 years $ 54,922 Options vested and expected to vest at June 30, 2019 8,580 $ 8.09 6.5 years $ 60,221
Schedule of Nonvested Share Activity	A summary of the status of the Company's non-vested stock options as of and for the nine months ended June 30, 2019 is presented below. (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Nonvested at beginning of period 3,335 $ 4.11 Granted 1,110 3.87 Vested (1,458 ) 2.62 Forfeited (494 ) 4.31 Nonvested at end of period 2,493 $ 4.87 The total fair value of options vested during the nine months ended June 30, 2019 , was $3,819 .
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	The following is a summary of the RSU activity for the nine months ended June 30, 2019 . (In thousands, except per share amounts) Shares Weighted Average Grant Date Fair Value/Share Outstanding at September 30, 2018 1,213 $ 20.88 Granted 880 12.68 Vested (24 ) 20.75 Forfeited (60 ) 16.58 Outstanding at June 30, 2019 2,009 $ 17.42 Vested and expected to vest at June 30, 2019 1,914 $ 17.50

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Aggregate Future Minimum Rental Payments for Operating Leases	Future minimum aggregate rental payments under non-cancelable operating leases are as follows: Fiscal Year Remainder of 2019 $ 4,287 2020 15,409 2021 11,761 2022 7,810 2023 5,499 Thereafter 11,446 Total $ 56,212
Schedule of Capital Leased Assets [Table Text Block]	The gross and net carrying values of the equipment under capital leases as of June 30, 2019 and September 30, 2018 was as follows: June 30, September 30, Gross carrying amount $ 60,923 $ 52,314 Net carrying amount 33,372 31,116
Schedule of Future Minimum Lease Payments for Capital Leases	The following is a schedule showing the future minimum lease payments under capital leases by years and the present value of the minimum lease payments as of June 30, 2019 . Fiscal Year Remainder of 2019 $ 4,229 2020 12,303 2021 9,031 2022 6,415 2023 4,112 Thereafter 4,466 Total 40,556 Less amount representing interest (at rates ranging from 1.71% to 9.71%) 8,402 Present value of net minimum capital lease payments 32,154 Less current installments of obligations under capital leases 12,830 Obligations under capital leases, excluding current installments $ 19,324
Schedule of Future Minimum Lease Payments Receivable under Operating Leases	As of June 30, 2019 , future minimum lease payments receivable under operating leases are as follows: Fiscal year Remainder of 2019 $ 746 2020 6,357 2021 5,385 2022 5,444 2023 4,462 Thereafter 61,407 Future minimum lease payments $ 83,801

Accrued Expenses and Other Li_2

Accrued Expenses and Other Liabilities (Tables)	9 Months Ended
	Jun. 30, 2019
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses and other liabilities consisted of the following: June 30, September 30, Salaries, wages and other benefits $ 27,397 $ 34,688 Obligation under capital leases 12,830 12,236 Third party commissions 10,262 5,097 Taxes, other than income 5,571 11,561 Insurance liabilities 4,705 5,005 Provisions for litigation 1,856 1,137 Severance payments 1,644 710 Earn-outs related to acquisitions 918 770 Other 24,090 26,468 $ 89,273 $ 97,672

Business Segments (Tables)

Business Segments (Tables)	9 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Schedule of segment reporting information, by segment	Three Months Ended Nine Months Ended 2019 2018 2019 2018 Total sales Integrated Solutions and Services $ 227,815 $ 211,238 $ 669,031 $ 613,503 Applied Product Technologies 158,526 152,835 437,196 425,388 Total sales 386,341 364,073 1,106,227 1,038,891 Intersegment sales Integrated Solutions and Services 2,386 1,902 6,240 7,786 Applied Product Technologies 23,612 19,696 68,014 57,890 Total intersegment sales 25,998 21,598 74,254 65,676 Sales to external customers Integrated Solutions and Services 225,429 209,336 662,791 605,717 Applied Product Technologies 134,914 133,139 369,182 367,498 Total sales 360,343 342,475 1,031,973 973,215 Earnings before interest, taxes, depreciation and amortization (EBITDA) Integrated Solutions and Services 51,380 41,473 144,589 132,785 Applied Product Technologies 26,874 32,201 51,504 72,332 Corporate (27,018 ) (37,274 ) (92,496 ) (92,718 ) Total EBITDA 51,236 36,400 103,597 112,399 Depreciation and amortization Integrated Solutions and Services 14,035 12,253 42,307 34,875 Applied Product Technologies 4,350 4,146 13,142 12,040 Corporate 5,760 5,163 15,948 15,009 Total depreciation and amortization 24,145 21,562 71,397 61,924 Operating profit (loss) Integrated Solutions and Services 37,345 29,220 102,282 97,910 Applied Product Technologies 22,524 28,055 38,362 60,292 Corporate (32,778 ) (42,437 ) (108,444 ) (107,727 ) Total operating profit 27,091 14,838 32,200 50,475 Interest expense (14,842 ) (12,370 ) (43,759 ) (40,423 ) Income (loss) before income taxes 12,249 2,468 (11,559 ) 10,052 Income tax (expense) benefit (7,959 ) (1,433 ) 1,134 960 Net income (loss) $ 4,290 $ 1,035 $ (10,425 ) $ 11,012 Capital expenditures Integrated Solutions and Services $ 19,646 $ 15,672 $ 53,303 $ 37,595 Applied Product Technologies 1,720 4,688 5,988 8,563 Corporate 1,900 2,539 4,657 8,411 Total capital expenditures $ 23,266 $ 22,899 $ 63,948 $ 54,569 June 30, September 30, Assets Integrated Solutions and Services $ 745,280 $ 711,622 Applied Product Technologies 666,206 677,993 Corporate 259,969 274,002 Total assets $ 1,671,455 $ 1,663,617 Goodwill Integrated Solutions and Services $ 221,986 $ 224,370 Applied Product Technologies 188,300 186,976 Total goodwill $ 410,286 $ 411,346

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Schedule of earnings per share, basic and diluted	The following table sets forth the computation of basic and diluted earnings (loss) from continuing operations per common share (in thousands, except per share amounts): Three Months Ended Nine Months Ended 2019 2018 2019 2018 Numerator: Numerator for basic and diluted loss per common share—Net income (loss) attributable to Evoqua Water Technologies Corp. $ 4,135 $ 793 $ (11,211 ) $ 9,585 Denominator: Denominator for basic net income (loss) per common share—weighted average shares 114,653 113,842 114,653 113,842 Effect of dilutive securities: Share‑based compensation 4,781 5,205 — 6,094 Denominator for diluted net income (loss) per common share—adjusted weighted average shares 119,434 119,047 114,653 119,936 Basic earnings (loss) attributable to Evoqua Water Technologies Corp. per common share $ 0.04 $ 0.01 $ (0.10 ) $ 0.08 Diluted earnings (loss) attributable to Evoqua Water Technologies Corp. per common share $ 0.03 $ 0.01 $ (0.10 ) $ 0.08

Description of the Company an_3

Description of the Company and Basis of Presentation (Details) $ / shares in Units, shares in Thousands, $ in Thousands	Oct. 30, 2018	Oct. 29, 2018	Mar. 21, 2018shares	Mar. 19, 2018shares	Nov. 07, 2017shares	Nov. 06, 2017$ / sharesshares	Jan. 16, 2014USD ($)	Jun. 30, 2019$ / shares	Dec. 31, 2017USD ($)	Jun. 30, 2019segment$ / shares	Sep. 30, 2018$ / shares
Subsidiary, Sale of Stock [Line Items]
Common stock, par value (in USD per share) | $ / shares								$ 0.01		$ 0.01	$ 0.01
Repayments of debt | $									$ 104,936
Number of reportable segments	2	3						2		2
IPO
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)						27,777
Common stock, par value (in USD per share) | $ / shares						$ 0.01
Proceeds from issuance of common stock | $									$ 137,605
Initial Public Offering - Shares from Existing Shareholders
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)			2,625	17,500		8,333
Initial Public Offering - Shares from The Company
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)						19,444
Over-Allotment Option
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)					4,167
EWT Holdings II Corp and EWT Holdings III Corp
Subsidiary, Sale of Stock [Line Items]
Stock purchase price, net of cash received | $							$ 730,577

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Nov. 28, 2018	Dec. 31, 2017	Nov. 30, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Oct. 01, 2018	Oct. 28, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization of debt issuance costs and discounts				$ 498	$ 478	$ 1,481	$ 1,932
Write off of deferred debt issuance cost		$ 1,150	$ 1,844			0	2,994
Prepayment of debt			$ 100,000
Foreign currency losses (gains) on intracompany loans				(772)	9,340	4,636	5,652
Research and development costs				3,281	$ 3,682	$ 11,384	$ 12,356
Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life						1 year
Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life						26 years
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
Tack-On Financing Completed October 28, 2016
Finite-Lived Intangible Assets [Line Items]
Debt instrument, fee amount									$ 2,131
Interest Rate Cap
Finite-Lived Intangible Assets [Line Items]
Cash paid for interest rate cap	$ 2,235
Derivative, Term of Contract	3 years
Amortization				$ 187		$ 435
Accounting Standards Update 2016-16 [Member]
Finite-Lived Intangible Assets [Line Items]
Cumulative effect of adoption of new accounting standards								$ 181
Accounting Standards Update 2014-09
Finite-Lived Intangible Assets [Line Items]
Cumulative effect of adoption of new accounting standards								$ (1,582)

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Treated Water Outsourcing) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Variable Interest Entity [Line Items]
Assets, Current	$ 565,088		$ 565,088		$ 565,560
Operating Expenses	(84,765)	$ (94,531)	(267,501)	$ (255,582)
Income from operations	27,091	14,838	32,200	50,475
Property, plant, and equipment, net	341,404		341,404		320,023
Goodwill	410,286		410,286		411,346
Other non‑current assets	24,117		24,117		23,842
Liabilities	(1,307,864)		(1,307,864)		(1,301,601)
Treated Water Outsourcing
Variable Interest Entity [Line Items]
Cash	5,921		5,921		3,304
Assets, Current	6,321		6,321		5,486
Revenues	2,573	3,020	8,951	12,586
Operating Expenses	(2,231)	(2,535)	(7,267)	(9,732)
Income from operations	342	$ 485	1,684	$ 2,854
Property, plant, and equipment, net	4,176		4,176		4,441
Goodwill	2,206		2,206		2,206
Other non‑current assets	3		3		3
Liabilities	$ (4,106)		$ (4,106)		$ (3,608)

Acquisitions and Divestitures N

Acquisitions and Divestitures Narrative (Details) - ATG UV [Member] £ in Thousands, $ in Thousands	May 25, 2019GBP (£)	May 25, 2019USD ($)	Jun. 30, 2019USD ($)
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	£ 5,500	$ 6,931
Business Acquisition, Transaction Costs			$ 488

Acquisitions and Divestitures O

Acquisitions and Divestitures Opening Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2019	May 25, 2019	Sep. 30, 2018
Business Acquisition [Line Items]
Goodwill	$ 410,286		$ 411,346
ATG UV [Member]
Business Acquisition [Line Items]
Current assets		$ 6,169
Property, plant and equipment		441
Goodwill		1,610
Intangible assets		1,550
Total assets acquired		9,770
Total liabilities assumed		(2,839)
Net assets acquired		$ 6,931

Revenue (Details)

Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Oct. 01, 2018	Sep. 30, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract assets	$ 70,018		$ 70,018			$ 69,147
Work in progress	19,934		19,934			19,461
Contract liabilities	32,312		32,312			17,652
Revenue from product sales and services	360,343	$ 342,475	1,031,973	$ 973,215
Cost of product sales and services	249,049	$ 240,468	736,338	$ 674,832
Inventories, net	161,020		161,020			$ 134,988
Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect of adoption of new accounting standards					$ (1,582)
Contract assets					(6,106)
Work in progress					6,194
Contract liabilities					$ 1,773
Revenue from product sales and services	325,009		934,111
Transferred over Time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue from product sales and services	135,522		383,659
Transferred over Time | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract assets	756		756
Revenue from product sales and services	1,009		(756)
Cost of product sales and services	1,264		131
Inventories, net	(131)		(131)
Revenue recognized at point in time | Transferred over Time | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue from product sales and services	1,640		$ 249
Minimum | Transferred at Point in Time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue from product sales and services	$ 100

Revenue (Performance Obligation

Revenue (Performance Obligation) (Details) $ in Thousands	Jun. 30, 2019USD ($)
Revenue, Performance Obligation [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 125,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months

Revenue (Information regarding

Revenue (Information regarding the Source of Revenue) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		$ 360,343	$ 342,475	$ 1,031,973	$ 973,215
Operating Leases, Income Statement, Lease Revenue	[1]	35,334		97,862
Accounting Standards Update 2014-09
Disaggregation of Revenue [Line Items]
Revenue from product sales and services		$ 325,009		$ 934,111
[1]	Other revenue relates to revenue recognized from Topic 840, Leases, mainly attributable to long term rentals.

Revenue (Disaggregation of Reve

Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	$ 360,343	$ 342,475	$ 1,031,973	$ 973,215
United States
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	284,737		823,923
Canada
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	20,873		58,836
Europe
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	26,677		71,235
Asia
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	23,007		62,411
Australia
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	5,049		15,568
Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	225,429		662,791
Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	134,914		369,182
Revenue from aftermarket
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	74,841		213,660
Revenue from aftermarket | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	29,968		93,238
Revenue from aftermarket | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	44,873		120,422
Revenue from service
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	149,980	$ 130,989	434,654	$ 390,242
Revenue from service | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	143,329		416,781
Revenue from service | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	6,651		17,873
Revenue from capital projects
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	135,522		383,659
Revenue from capital projects | Integrated Solutions and Services
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	52,132		152,772
Revenue from capital projects | Applied Product Technologies
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	$ 83,390		$ 230,887

Revenue (Contract Assets and Li

Revenue (Contract Assets and Liabilities) (Details) $ in Thousands	9 Months Ended
	Jun. 30, 2019USD ($)
Change in Contract with Customer, Asset [Roll Forward]
September 30, 2018	$ 69,147
Cumulative effect of adoption of new accounting standards	(6,106)
Recognized in current period	225,341
Reclassified to accounts receivable	(218,433)
Foreign currency	69
June 30, 2019	70,018
Change in Contract with Customer, Liability [Roll Forward]
September 30, 2018	17,652
Cumulative effect of adoption of new accounting standards	1,773
Recognized in current period	214,444
Amounts in beginning balance reclassified to revenue	(20,127)
Current period amounts reclassified to revenue	(181,266)
Foreign currency	(164)
June 30, 2019	$ 32,312

Fair Value Measurements (Detail

Fair Value Measurements (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Quoted Market Prices in Active Markets (Level 1)
Deferred compensation plan assets
Trust Assets	$ 401	$ 648
Fair Value, Inputs, Level 2
Assets:
Foreign currency forward contracts	102	345
Deferred compensation plan assets
Insurance	17,978	18,448
Liabilities:
Pension plan	(34,625)	(35,541)
Deferred compensation plan liabilities	(20,464)	(21,834)
Foreign currency forward contracts	(376)	(67)
Long‑term debt	(954,455)	(957,441)
Fair Value, Inputs, Level 3
Liabilities:
Earn-outs related to acquisitions	(2,064)	(1,916)
Cash | Quoted Market Prices in Active Markets (Level 1)
Assets:
Defined benefit plan, fair value of plan assets	14,678	15,821
US Government Agencies Debt Securities
Assets:
Plan assets at net asset value	2,330	3,161
Liability Driven Investment
Assets:
Plan assets at net asset value	5,167	2,598
Guernsey Unit Trust
Assets:
Plan assets at net asset value	961	965
Global Absolute Return
Assets:
Plan assets at net asset value	$ 2,015	$ 2,038

Fair Value Measurements (Rollfo

Fair Value Measurements (Rollforward of Earn-outs) (Details) - Fair Value, Inputs, Level 3 - Fair Value, Measurements, Recurring - USD ($) $ in Thousands		9 Months Ended
		Jun. 30, 2019	Sep. 30, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Payments		$ (993)
Earn-outs related to acquisitions		2,064	$ 1,916
Fair value increase		1,143
Foreign currency		(2)
Other Current Liabilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Payments		(993)
Earn-outs related to acquisitions	[1]	918	770
Fair value increase	[1]	1,143
Foreign currency	[1]	(2)
Other Noncurrent Liabilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Payments		0
Earn-outs related to acquisitions	[2]	1,146	$ 1,146
Fair value increase	[2]	0
Foreign currency	[2]	$ 0
[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 (Details)

Accounts Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Receivables [Abstract]
Accounts receivable	$ 252,014	$ 258,955
Allowance for doubtful accounts	(4,297)	(4,199)
Accounts receivable, net	$ 247,717	$ 254,756

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 78,087	$ 69,176
Work in progress	19,934	19,461
Finished goods and products held for resale	67,012	53,786
Costs of unbilled projects	7,644	1,878
Reserves for excess and obsolete	(11,657)	(9,313)
Inventory, Net	$ 161,020	$ 134,988

Property, Plant, and Equipmen_2

Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 595,934		$ 595,934		$ 536,881
Less: accumulated depreciation	(254,530)		(254,530)		(216,858)
Property, plant, and equipment, net	341,404		341,404		320,023
Depreciation and amortization	15,979	$ 14,530	47,334	$ 42,518
Maintenance and repair expense	6,144	$ 6,238	18,192	$ 17,620
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	452,386		452,386		399,619
Land and buildings
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	76,571		76,571		76,459
Construction in process
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 66,977		$ 66,977		$ 60,803

Property, Plant, and Equipmen_3

Property, Plant, and Equipment Property, Plant and Equipment (Secured Financing Agreements) (Details) - Equipment Financings $ in Thousands	Jun. 30, 2019USD ($)
Property, plant and equipment gross [Member]
Debt Instrument [Line Items]
Pledged Assets, Not Separately Reported, Other	$ 28,240
Property, plant and equipment gross [Member] | Machinery and equipment
Debt Instrument [Line Items]
Pledged Assets, Not Separately Reported, Other	20,385
Property, plant and equipment gross [Member] | Construction in process
Debt Instrument [Line Items]
Pledged Assets, Not Separately Reported, Other	7,855
Property, plant and equipment net [Member]
Debt Instrument [Line Items]
Pledged Assets, Not Separately Reported, Other	22,801
Property, plant and equipment net [Member] | Machinery and equipment
Debt Instrument [Line Items]
Pledged Assets, Not Separately Reported, Other	14,946
Property, plant and equipment net [Member] | Construction in process
Debt Instrument [Line Items]
Pledged Assets, Not Separately Reported, Other	$ 7,855

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Business acquisition, goodwill, expected tax deductible, amount	$ 150,218	$ 147,861

Goodwill (Schedule of Goodwill)

Goodwill (Schedule of Goodwill) (Details) $ in Thousands	9 Months Ended
	Jun. 30, 2019USD ($)
Goodwill [Line Items]
Goodwill, Acquired During Period	$ 1,610
Goodwill [Roll Forward]
Goodwill, beginning of the period	411,346
Measurement period adjustment	(1,874)
Foreign currency translation	(796)
Goodwill, end of the period	410,286
Operating Segments | Integrated Solutions and Services
Goodwill [Line Items]
Goodwill, Acquired During Period	0
Goodwill [Roll Forward]
Goodwill, beginning of the period	224,370
Measurement period adjustment	(1,937)
Foreign currency translation	(447)
Goodwill, end of the period	221,986
Operating Segments | Applied Product Technologies
Goodwill [Line Items]
Goodwill, Acquired During Period	1,610
Goodwill [Roll Forward]
Goodwill, beginning of the period	186,976
Measurement period adjustment	63
Foreign currency translation	(349)
Goodwill, end of the period	$ 188,300

Debt (Term Facility and Revolvi

Debt (Term Facility and Revolving Credit Facility) (Details) - USD ($) $ in Thousands	Jan. 15, 2014	Dec. 31, 2017	Jun. 30, 2019	Sep. 30, 2018	Jun. 30, 2018	Jul. 26, 2018	Dec. 20, 2017	Sep. 30, 2017
Line of Credit Facility [Line Items]
Unamortized discount (premium) and debt issuance costs, net			$ 12,647	$ 14,129
Long-term debt, gross			960,815	953,759
Letters of credit outstanding, amount				11,777
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, remaining borrowing capacity			125,000	125,000			$ 125,000	$ 95,000
Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 35,000
Debt instrument, unused borrowing capacity, amount			111,738	113,223
Letters of credit outstanding, amount			$ 13,262	11,777
Minimum
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage			6.26%
Maximum
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage			7.39%
First Lien Term Facility, due December 20, 2024
Line of Credit Facility [Line Items]
Debt instrument, term	7 years
Unamortized discount (premium) and debt issuance costs, net			$ 12,647	14,129
First Lien Term Facility, due December 20, 2024 | Term Loan
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 505,000
Debt instrument, interest rate, stated percentage			5.44%
Debt instrument, periodic payment, principal				2,369	$ 1,991
Line of credit facility, remaining borrowing capacity						$ 150,000
First Lien Term Facility, due December 20, 2024 | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 75,000
Second Lien Term Facility
Line of Credit Facility [Line Items]
Debt instrument, term	8 years
Second Lien Term Facility | Term Loan
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 75,000
London Interbank Offered Rate (LIBOR) | First Lien Term Facility, due December 20, 2024 | Term Loan
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage			2.44%
Debt instrument, basis spread on variable rate			3.00%
Line of Credit | Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			$ 45,000				$ 45,000
Letters of credit outstanding, amount			214	64
Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term debt, gross			$ 0	$ 0
Ratings Condition Period | London Interbank Offered Rate (LIBOR) | Maximum | Term Loan
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate		3.75%
Other than Ratings Condition Period | London Interbank Offered Rate (LIBOR) | Minimum | Term Loan
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate		3.00%

Debt (Schedule of Long-term Deb

Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Total debt	$ 960,815	$ 953,759
Less unamortized discount and lender fees	(12,647)	(14,129)
Total net debt	948,168	939,630
Current portion of debt	(12,661)	(11,555)
Total long‑term debt	935,507	928,075
First Lien Term Facility, due December 20, 2024
Debt Instrument [Line Items]
Total debt	931,123	938,230
Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	0	0
Notes Payable, due August 31, 2019 to July 31, 2023
Debt Instrument [Line Items]
Total debt	1,710	2,106
Equipment Financings | Equipment Financing, due June 30, 2024 to May 21, 2026
Debt Instrument [Line Items]
Total debt	26,252	11,588
MAGENTO | Facility Financing | Mortgage, due June 30, 2028
Debt Instrument [Line Items]
Total debt	$ 1,730	$ 1,835

Debt (Long-term Debt Maturities

Debt (Long-term Debt Maturities) (Details) $ in Thousands	Jun. 30, 2019USD ($)
Debt Disclosure [Abstract]
Remainder of 2019	$ 3,168
2020	12,702
2021	12,835
2022	12,977
2023	12,860
Thereafter	906,273
Long-term Debt	$ 960,815

Debt (Equipment Financing) (Det

Debt (Equipment Financing) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Total debt	$ 960,815	$ 953,759
Equipment Financing, due June 30, 2024 to May 21, 2026 | Equipment Financings
Debt Instrument [Line Items]
Total debt	$ 26,252	$ 11,588
Minimum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	6.26%
Minimum | Equipment Financing, due June 30, 2024 to May 21, 2026 | Equipment Financings
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	5.08%
Maximum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	7.39%
Maximum | Equipment Financing, due June 30, 2024 to May 21, 2026 | Equipment Financings
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	6.55%

Debt (Notes Payable) (Details)

Debt (Notes Payable) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Notes Payable	$ 1,710	$ 2,106
Minimum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	6.26%
Maximum
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	7.39%

Debt (Mortgage) (Details)

Debt (Mortgage) (Details) € in Thousands, $ in Thousands	Jun. 29, 2018EUR (€)	Jun. 30, 2019USD ($)	Sep. 30, 2018USD ($)
Debt Instrument [Line Items]
Total debt		$ 960,815	$ 953,759
MAGENTO | Mortgage, due June 30, 2028 | Facility Financing
Debt Instrument [Line Items]
Debt instrument, term	10 years
Debt Instrument, Face Amount	€ 1,600	1,822
Debt instrument, periodic payment, principal	€ 7	8
Debt instrument, interest rate, stated percentage	2.40%
Total debt		$ 1,730	$ 1,835

Derivative Financial Instrume_3

Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Nov. 28, 2018	Jun. 30, 2019	Jun. 30, 2019
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred			$ (149)
Interest rate cap amortization to be recognized in earnings within twelve months			$ (745)
Description of Reclassification of Cash Flow Hedge Gain (Loss)			twelve months
Interest Rate Cap
Derivative [Line Items]
Derivative, Term of Contract	3 years
Derivative, Cap Interest Rate	3.50%
Cash paid for interest rate cap	$ 2,235
Unamortized Premium, Interest Rate Cap		$ 1,800	$ 1,800
Amortization		187	435
Foreign Exchange Forward
Derivative [Line Items]
Derivative, Notional Amount		30,003	30,003
Designated as Hedging Instrument | Interest Rate Cap
Derivative [Line Items]
Derivative, Notional Amount	$ 600,000
Prepaid Expenses and Other Current Assets | Interest Rate Cap
Derivative [Line Items]
Unamortized Premium, Interest Rate Cap		745	745
Other Noncurrent Assets [Member] | Interest Rate Cap
Derivative [Line Items]
Unamortized Premium, Interest Rate Cap		$ 1,055	$ 1,055

Derivative Financial Instrume_4

Derivative Financial Instruments (Fair Values) (Details) - Fair Value, Inputs, Level 2 - Fair Value, Measurements, Recurring - Designated as Hedging Instrument - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Other Current Liabilities
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Liability at Fair Value	$ 376	$ 67
Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Interest rate cap	56	0
Foreign Currency Cash Flow Hedge Asset at Fair Value	$ 102	$ 282

Derivative Financial Instrume_5

Derivative Financial Instruments (Amounts Recognized in AOCI) (Details) - Other Comprehensive Income (Loss) - Designated as Hedging Instrument - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest Rate Cap
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	$ (78)	$ 0	$ 56	$ 0
Foreign Exchange Forward
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	$ (173)	$ (3)	$ (487)	$ 0

Derivative Financial Instrume_6

Derivative Financial Instruments (Derivatives Not Designated as Cash Flow Hedges) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring | Not Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Asset at Fair Value	$ 0	$ 63

Product Warranties (Details)

Product Warranties (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance at beginning of the period	$ 8,907
Balance at beginning of the period	3,360
Balance at end of the period	8,264
Balance at end of the period	3,741
Other Current Liabilities
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance at beginning of the period	8,907	$ 11,164
Warranty provision for sales	4,134	2,540
Settlement of warranty claims	(4,896)	(5,511)
Foreign currency translation and other	119	(433)
Balance at end of the period	8,264	7,760
Other Noncurrent Liabilities
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance at beginning of the period	3,360	6,110
Warranty provision for sales	1,148	157
Settlement of warranty claims	(509)	(2,710)
Foreign currency translation and other	(258)	(12)
Balance at end of the period	$ 3,741	$ 3,545

Restructuring and Related Cha_3

Restructuring and Related Charges (Details) $ in Thousands	Oct. 30, 2018USD ($)	Oct. 29, 2018	Jun. 30, 2019USD ($)	Jun. 30, 2019USD ($)segment	Jun. 30, 2018USD ($)
Restructuring Cost and Reserve [Line Items]
Number of reportable segments	2	3	2	2
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning of the period				$ 710	$ 3,542
Restructuring charges				10,840	8,273
Restructuring charges related to other initiatives				2,086	8,752
Write off charge and other non‑cash activity				(520)	(479)
Cash payments				(9,830)	(11,395)
Other adjustments				(76)	24
Restructuring reserve, end of the period			$ 1,644	1,644	444
Cost of Product Sales and Services
Restructuring Reserve [Roll Forward]
Restructuring charges				4,912	3,086
General and Administrative Expense
Restructuring Reserve [Roll Forward]
Restructuring charges				4,929	3,830
Sales and Marketing Expense
Restructuring Reserve [Roll Forward]
Restructuring charges				891	750
Research and Development Expense
Restructuring Reserve [Roll Forward]
Restructuring charges				108	607
Two-segment realignment
Restructuring Reserve [Roll Forward]
Restructuring charges				$ 9,274	$ 0
Two-segment realignment | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 22,000
Two-segment realignment | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	17,000
Other Restructuring [Member] | Two-segment realignment | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	7,000
Other Restructuring [Member] | Two-segment realignment | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 6,000

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Retirement Benefits [Abstract]
Service cost	$ 214	$ 230	$ 648	$ 705
Interest cost	118	116	357	357
Expected return on plan assets	(30)	(30)	(90)	(93)
Amortization of actuarial losses	95	75	288	230
Pension expense for defined benefit plans	$ 397	$ 391	$ 1,203	$ 1,199

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Estimated Annual Effective Tax Rate Used to Calculate Income Tax Expense (Benefit)			38.90%	13.00%
Federal statutory income tax rate, percent		24.50%	21.00%	22.80%	35.00%
Effective income tax rate reconciliation, percent	65.00%	58.10%	9.80%	9.60%
Income tax (expense) benefit	$ (7,959)	$ (1,433)	$ 1,134	$ 960
Income (loss) before income taxes	$ 12,249	$ 2,468	$ (11,559)	10,052
Tax Cuts and Jobs Act, Change in Tax Rate, Deferred Tax Liability, Income Tax Benefit				$ 3,641

Share-Based Compensation (Detai

Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 01, 2019	Dec. 21, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value, exercises in period					$ 4,608
Employee Stock Ownership Plan (ESOP), Shares in ESOP		11,297
Common stock, par value (in USD per share)			$ 0.01		$ 0.01		$ 0.01
Non-cash share-based compensation			$ 4,978	$ 4,405	$ 14,248	$ 11,257
Share-based Compensation expense			4,985		14,308
Compensation cost not yet recognized, period for recognition			$ 13,002		13,002
Fair value of options vested					$ 3,819
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			1,197,000		1,197,000
Proceeds from issuance of common stock			$ 0	$ 0	$ 341	$ 137,605
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity incentive plan, number of shares authorized (shares)			5,100,000		5,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			1,985,000		1,985,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity incentive plan, number of shares authorized (shares)			11,083,000		11,083,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			1,704,000		1,704,000
Compensation cost not yet recognized, period for recognition			$ 10,218		$ 10,218
Period for recognition for unrecognized compensation expense			2 years 8 months
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for recognition for unrecognized compensation expense			1 year 4 months
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			2,009,000		2,009,000		1,213,000
Aggregate value			$ 25,000		$ 25,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Stock Ownership Plan (ESOP), Shares in ESOP		5,000
Common stock, par value (in USD per share)		$ 0.01
Employee Stock Ownership Plan (ESOP), Compensation Expense			$ 0		$ 293
Shares issued under ESPP	46,000
Evoqua Water Technologies Corp. Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards vesting percentage			25.00%
Expiration period			10 years

Share-Based Compensation (Stock

Share-Based Compensation (Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Jun. 30, 2019	Sep. 30, 2018
Share-based Payment Arrangement [Abstract]
Intrinsic value, exercises in period	$ 4,608
Options
Outstanding at beginning of the period (shares)	8,973,000
Granted (shares)	1,110,000
Exercised (shares)	(890,000)
Cancelled (shares)	(23,000)
Forfeited (shares)	(494,000)
Expired (shares)	0
Outstanding at end of the period (shares)	8,676,000	8,973,000
Options exercisable (shares)	6,183,000
Options vested and expected to vest (shares)	8,580,000
Weighted Average Exercise Price/Share
Weighted average exercise price, outstanding, beginning balance (in dollars per share)	$ 7.57
Weighted average exercise price, granted (in dollars per share)	12.73
Weighted average exercise price, exercised (in dollars per share)	5.25
Weighted average exercise price, cancelled (in dollars per share)	20.88
Weighted average exercise price, forfeited (in dollars per share)	12.24
Weighted average exercise price, expired (in dollars per share)	0
Weighted average exercise price, outstanding, ending balance (in dollars per share)	8.16	$ 7.57
Weighted average exercise price, exercisable (in dollars per share)	5.66
Weighted average exercise price, options vested and expected to vest (in dollars per share)	$ 8.09
Weighted Average Remaining Contractual Term
Weighted average remaining contractual term, outstanding	6 years 7 months	6 years 11 months
Weighted average contractual term, exercisable	5 years 7 months
Weighted average remaining contractual term, options vested and expected to vest	6 years 6 months
Intrinsic value, outstanding	$ 60,368	$ 95,864
Intrinsic value, exercisable	54,922
Intrinsic value, options vested and expected to vest	$ 60,221

Share-Based Compensation (Nonve

Share-Based Compensation (Nonvested Share Activity) (Details)	9 Months Ended
	Jun. 30, 2019$ / sharesshares
Shares
Nonvested at beginning of period | shares	3,335,000
Granted (shares) | shares	1,110,000
Vested (shares) | shares	(1,458,000)
Forfeited (shares) | shares	(494,000)
Nonvested at end of period | shares	2,493,000
Weighted Average Grant Date Fair Value/Share
Weighted average grant date fair value, nonvested, beginning balance (in dollars per share) | $ / shares	$ 4.11
Weighted average grant date fair value, granted (in dollars per share) | $ / shares	3.87
Weighted average grant date fair value, vested (in dollars per share) | $ / shares	2.62
Weighted average grant date fair value, forfeited (in dollars per share) | $ / shares	4.31
Weighted average grant date fair value, nonvested, ending balance (in dollars per share) | $ / shares	$ 4.87

Share-Based Compensation (RSU A

Share-Based Compensation (RSU Activity) (Details) shares in Thousands	9 Months Ended
	Jun. 30, 2019$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable (shares)	6,183
Shares
Forfeited	494
Outstanding at beginning of the period	1,197
Weighted Average Grant Date Fair Value/Share
Weighted average grant date fair value, forfeited (in dollars per share) | $ / shares	$ 4.31
Weighted average exercise price, options vested and expected to vest (in dollars per share) | $ / shares	$ 8.09
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable (shares)	1,914
Shares
Outstanding at beginning of the period (shares)	1,213
Granted	880
Vested in period (shares)	(24)
Forfeited	60
Outstanding at beginning of the period	2,009
Weighted Average Grant Date Fair Value/Share
Weighted average grant date fair value, nonvested, equity instruments other than options, beginning of the period (in dollar per share) | $ / shares	$ 20.88
Weighted average grant date fair value, granted (in dollars per share) | $ / shares	12.68
Weighted average grant date fair value, vested (in dollars per share) | $ / shares	20.75
Weighted average grant date fair value, forfeited (in dollars per share) | $ / shares	16.58
Weighted average grant date fair value, nonvested, equity instruments other than options, end of the period (in dollar per share) | $ / shares	17.42
Weighted average exercise price, options vested and expected to vest (in dollars per share) | $ / shares	$ 17.50

Concentration of Credit Risk (D

Concentration of Credit Risk (Details) - country	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Risks and Uncertainties [Abstract]
Concentration Risk, Customer	0	no
Concentration Risk, Percentage	10.00%	10.00%
Number of countries in which entity operates	8

Related_Party Transactions (Det

Related‑Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
AEA Investors LP
Related Party Transaction [Line Items]
Due to related parties	$ 0		$ 0		$ 0
Advisory Fees | AEA Investors LP
Related Party Transaction [Line Items]
Fees paid to related party			0	$ 333
Expenses Excluding Advisory Fees | AEA Investors LP
Related Party Transaction [Line Items]
Expenses from transactions with related party			18	43
Customer Relationships [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	636	$ 376	1,989	$ 961
Accounts Receivable, Related Parties	$ 788		$ 788		$ 3,139

Commitments and Contingencies_2

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Operating Leased Assets [Line Items]
Rent expense	$ 5,222	$ 4,091	$ 16,138	$ 13,843
Letters of credit outstanding, amount			11,777
Letter of Credit
Operating Leased Assets [Line Items]
Letters of credit outstanding, amount	13,262		11,777
Surety Bond [Member]
Operating Leased Assets [Line Items]
Surety bonds	138,138		123,427
Siemens [Member]
Operating Leased Assets [Line Items]
Letters of credit outstanding, amount	0		857
Siemens [Member] | Surety Bond [Member]
Operating Leased Assets [Line Items]
Surety bonds	$ 1,241		$ 2,469
Minimum
Operating Leased Assets [Line Items]
Lessor, operating lease, term of contract	5 years
Minimum | Surety Bond [Member]
Operating Leased Assets [Line Items]
Financial instruments, commitments, expiration period	12 months
Maximum
Operating Leased Assets [Line Items]
Lessor, operating lease, term of contract	20 years
Maximum | Surety Bond [Member]
Operating Leased Assets [Line Items]
Financial instruments, commitments, expiration period	10 years

Commitments and Contingencies_3

Commitments and Contingencies (Future Minimum Rental Payments for Operating Leases) (Details) $ in Thousands	Jun. 30, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2019	$ 4,287
2020	15,409
2021	11,761
2022	7,810
2023	5,499
Thereafter	11,446
Total	$ 56,212

Commitments and Contingencies_4

Commitments and Contingencies (Future Minimum Rental Payments under Capital Lease) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Capital Leased Assets [Line Items]
Remainder of 2019	$ 4,229
2020	12,303
2021	9,031
2022	6,415
2023	4,112
Thereafter	4,466
Total	40,556
Less amount representing interest (at rates ranging from 1.71% to 9.71%)	8,402
Present value of net minimum capital lease payments	32,154
Less current installments of obligations under capital leases	12,830	$ 12,236
Obligations under capital leases, excluding current installments	$ 19,324
Capital lease obligations | Minimum
Capital Leased Assets [Line Items]
Capital leases of lessee, basis spread on variable rate	1.71%
Capital lease obligations | Maximum
Capital Leased Assets [Line Items]
Capital leases of lessee, basis spread on variable rate	9.71%

Commitments and Contingencies_5

Commitments and Contingencies (Future Minimum Lease Payments Receivable under Operating Leases) (Details) $ in Thousands	Jun. 30, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2019	$ 746
2020	6,357
2021	5,385
2022	5,444
2023	4,462
Thereafter	61,407
Future minimum lease payments	$ 83,801

Commitments and Contingencies_6

Commitments and Contingencies (Capital Leased Assets) (Details) - Equipment - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Capital Leased Assets [Line Items]
Gross carrying amount	$ 60,923	$ 52,314
Net carrying amount	$ 33,372	$ 31,116

Accrued Expenses and Other Li_3

Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Payables and Accruals [Abstract]
Salaries, wages and other benefits	$ 27,397	$ 34,688
Obligation under capital leases	12,830	12,236
Third party commissions	10,262	5,097
Taxes, other than income	5,571	11,561
Insurance liabilities	4,705	5,005
Provisions for litigation	1,856	1,137
Severance payments	1,644	710
Earn-outs related to acquisitions	918	770
Other	24,090	26,468
Accrued expenses and other liabilities	$ 89,273	$ 97,672

Business Segments (Details)

Business Segments (Details) $ in Thousands	Oct. 30, 2018	Oct. 29, 2018	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)segment	Jun. 30, 2018USD ($)	Sep. 30, 2018USD ($)
Segment Reporting [Abstract]
Number of reportable segments	2	3	2		2
Segment Reporting Information [Line Items]
Revenue from product sales and services			$ 360,343	$ 342,475	$ 1,031,973	$ 973,215
Earnings before interest, taxes, depreciation and amortization (EBITDA)			51,236	36,400	103,597	112,399
Depreciation and amortization			24,145	21,562	71,397	61,924
Operating profit (loss)			27,091	14,838	32,200	50,475
Interest expense			(14,842)	(12,370)	(43,759)	(40,423)
Income (loss) before income taxes			12,249	2,468	(11,559)	10,052
Income tax (expense) benefit			(7,959)	(1,433)	1,134	960
Net (loss) income			4,290	1,035	(10,425)	11,012
Capital expenditures			23,266	22,899	63,948	54,569
Assets			1,671,455		1,671,455		$ 1,663,617
Goodwill			410,286		410,286		411,346
Integrated Solutions and Services
Segment Reporting Information [Line Items]
Revenue from product sales and services			225,429		662,791
Capital expenditures			19,646	15,672	53,303	37,595
Applied Product Technologies
Segment Reporting Information [Line Items]
Revenue from product sales and services			134,914		369,182
Capital expenditures			1,720	4,688	5,988	8,563
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue from product sales and services			25,998	21,598	74,254	65,676
Intersegment Eliminations | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Revenue from product sales and services			2,386	1,902	6,240	7,786
Intersegment Eliminations | Applied Product Technologies
Segment Reporting Information [Line Items]
Revenue from product sales and services			23,612	19,696	68,014	57,890
Operating Segments
Segment Reporting Information [Line Items]
Total sales			386,341	364,073	1,106,227	1,038,891
Operating Segments | Integrated Solutions and Services
Segment Reporting Information [Line Items]
Total sales			227,815	211,238	669,031	613,503
Revenue from product sales and services			225,429	209,336	662,791	605,717
Earnings before interest, taxes, depreciation and amortization (EBITDA)			51,380	41,473	144,589	132,785
Depreciation and amortization			14,035	12,253	42,307	34,875
Operating profit (loss)			37,345	29,220	102,282	97,910
Assets			745,280		745,280		711,622
Goodwill			221,986		221,986		224,370
Operating Segments | Applied Product Technologies
Segment Reporting Information [Line Items]
Total sales			158,526	152,835	437,196	425,388
Revenue from product sales and services			134,914	133,139	369,182	367,498
Earnings before interest, taxes, depreciation and amortization (EBITDA)			26,874	32,201	51,504	72,332
Depreciation and amortization			4,350	4,146	13,142	12,040
Operating profit (loss)			22,524	28,055	38,362	60,292
Assets			666,206		666,206		677,993
Goodwill			188,300		188,300		186,976
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Earnings before interest, taxes, depreciation and amortization (EBITDA)			(27,018)	(37,274)	(92,496)	(92,718)
Depreciation and amortization			5,760	5,163	15,948	15,009
Operating profit (loss)			(32,778)	(42,437)	(108,444)	(107,727)
Capital expenditures			1,900	$ 2,539	4,657	$ 8,411
Assets			$ 259,969		$ 259,969		$ 274,002

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Numerator for basic and diluted loss per common share—Net income (loss) attributable to Evoqua Water Technologies Corp.	$ 4,135	$ 793	$ (11,211)	$ 9,585
Denominator:
Denominator for basic net income (loss) per common share—weighted average shares	114,653	113,842	114,653	113,842
Effect of dilutive securities:
Share‑based compensation	4,781	5,205	0	6,094
Denominator for diluted net income (loss) per common share—adjusted weighted average shares	119,434	119,047	114,653	119,936
Basic loss per common share (in dollars per share)	$ 0.04	$ 0.01	$ (0.10)	$ 0.08
Diluted loss per common share (in dollars per share)	$ 0.03	$ 0.01	$ (0.10)	$ 0.08
Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (shares)			4,358

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ in Thousands	Jul. 05, 2019	Jun. 30, 2019	Sep. 30, 2018
Subsequent Event [Line Items]
Total debt		$ 960,815	$ 953,759
Equipment Financings | Equipment Financing, due June 30, 2024 to May 21, 2026
Subsequent Event [Line Items]
Total debt		$ 26,252	$ 11,588
Equipment Financings | Equipment Financing, due June 30, 2024 to May 21, 2026 | Subsequent Event
Subsequent Event [Line Items]
Total debt	$ 19,500
Debt instrument, interest rate, stated percentage	8.263%