CMC Materials (CCMP) 10-Q 8 May 20 2020 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Mar. 31, 2020	Apr. 30, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	000-30205
Entity Registrant Name	CABOT MICROELECTRONICS CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-4324765
Entity Address, Address Line One	870 North Commons Drive
Entity Address, City or Town	Aurora
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60504
City Area Code	630
Local Phone Number	375-6631
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	CCMP
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		29,063,259
Entity Central Index Key	0001102934
Current Fiscal Year End Date	--09-30
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue	$ 284,193	$ 265,391	$ 567,336	$ 487,169
Cost of sales	163,091	150,571	317,552	273,016
Gross profit	121,102	114,820	249,784	214,153
Operating expenses:
Research, development and technical	13,230	12,778	26,041	26,818
Selling, general and administrative	56,209	50,328	110,648	111,456
Total operating expenses	69,439	63,106	136,689	138,274
Operating income	51,663	51,714	113,095	75,879
Interest Expense	10,753	13,331	22,673	20,221
Interest income	143	568	458	1,587
Other income (expense), net	(1,010)	(1,014)	(1,407)	(2,425)
Income before income taxes	40,043	37,937	89,473	54,820
Provision for income taxes	7,144	10,800	18,025	14,240
Net income	$ 32,899	$ 27,137	$ 71,448	$ 40,580
Basic earnings per share (in dollars per share)	$ 1.12	$ 0.94	$ 2.45	$ 1.45
Diluted earnings per share (in dollars per share)	$ 1.11	$ 0.92	$ 2.41	$ 1.42
Weighted average basic shares outstanding (in shares)	29,287,211	28,997,632	29,182,528	28,065,759
Weighted average diluted shares outstanding (in shares)	29,725,179	29,479,114	29,666,436	28,607,033

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 32,899	$ 27,137	$ 71,448	$ 40,580
Other comprehensive income, net of tax:
Foreign currency translation adjustments	(19,725)	(992)	(3,874)	1,433
Minimum pension liability adjustment	0	251	0	0
Net unrealized loss on cash flow hedges	(17,307)	(6,474)	(13,048)	(6,474)
Other comprehensive income, net of tax	(37,032)	(7,215)	(16,922)	(5,041)
Comprehensive income (loss)	$ (4,133)	$ 19,922	$ 54,526	$ 35,539

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Current assets:
Cash and cash equivalents	$ 340,702	$ 188,495
Accounts receivable, less allowance for doubtful accounts of $2,718 at March 31, 2020 and $2,377 at September 30, 2019	151,959	146,113
Inventories	157,872	145,278
Prepaid expenses and other current assets	25,768	28,670
Total current assets	676,301	508,556
Property, plant and equipment, net	320,846	276,818
Goodwill	709,823	710,071
Other intangible assets, net	708,659	754,044
Deferred income taxes	6,607	6,566
Other long-term assets	37,724	5,711
Total assets	2,459,960	2,261,766
Current liabilities:
Accounts payable	58,803	54,529
Short-term debt	150,000	0
Current portion of long-term debt	10,650	13,313
Accrued expenses, income taxes payable and other current liabilities	109,389	103,618
Total current liabilities	328,842	171,460
Long-term debt, net of current portion, less prepaid debt issuance costs of $16,420 at March 31, 2020 and $17,900 at September 30, 2019	914,617	928,463
Deferred income taxes	112,780	121,993
Other long-term liabilities	94,311	59,473
Total liabilities	1,450,550	1,281,389
Commitments and contingencies (Note 13)
Stockholders’ equity:
Common Stock Authorized: 200,000,000 shares, $0.001 par value; Issued: 39,854,529 shares at March 31, 2020, and 39,592,468 shares at September 30, 2019	40	40
Capital in excess of par value of common stock	1,008,311	988,980
Retained earnings	508,126	461,501
Accumulated other comprehensive income (loss)	(40,648)	(23,238)
Treasury stock at cost, 10,672,652 shares at March 31, 2020, and 10,491,252 shares at September 30, 2019	(466,419)	(446,906)
Total stockholders’ equity	1,009,410	980,377
Total liabilities and stockholders’ equity	$ 2,459,960	$ 2,261,766

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 2,718	$ 2,377
Prepaid debt issuance cost	$ 16,420	$ 17,900
Common stock, authorized (in shares)	200,000,000	200,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, issued (in shares)	39,854,529	39,592,468
Treasury stock (in shares)	10,672,652	10,491,252

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net income	$ 71,448	$ 40,580
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	64,192	43,889
Accretion on Asset Retirement Obligations - Liabilities	255	0
Provision for doubtful accounts	185	(314)
Share-based compensation expense	8,997	11,708
Deferred income tax expense (benefit)	(7,117)	(13,811)
Non-cash foreign exchange (gain) loss	325	354
Loss (Gain) on disposal of property, plant and equipment	(69)	(58)
Non-cash charge on inventory step up of acquired inventory sold	0	14,827
Amortization of debt issuance costs	1,565	1,286
Other	959	2,337
Changes in operating assets and liabilities:
Accounts receivable	(6,386)	9,445
Inventories	(13,103)	(21,100)
Prepaid expenses and other assets	5,020	5,415
Accounts payable	(1,102)	(429)
Accrued expenses, income taxes payable and other liabilities	(12,830)	(40,601)
Net cash provided by operating activities	112,339	53,528
Net Cash Provided by (Used in) Investing Activities [Abstract]
Additions to property, plant and equipment	(59,192)	(19,472)
Proceeds from sales of property, plant and equipment	1,587	1,210
Acquisition of a business, net of cash acquired	0	(1,182,186)
Cash settlement of life insurance policy	0	3,959
Net cash used in investing activities	(57,605)	(1,196,489)
Cash flows from financing activities:
Repayment of long-term debt	(17,988)	(45,000)
Repurchases of common stock	(19,513)	(4,695)
Proceeds from issuance of long-term debt	0	1,062,337
Proceeds from revolving line of credit	150,000	0
Debt issuance costs	0	(18,745)
Principal payments under financing lease obligations	(4)
Proceeds from issuance of stock	10,334	10,361
Dividends paid	(24,752)	(21,934)
Net cash provided by financing activities	98,077	982,324
Effect of exchange rate changes on cash	(604)	(24)
Increase (decrease) in cash and cash equivalents	152,207	(160,661)
Cash and cash equivalents at beginning of period	188,495	352,921
Cash and cash equivalents at end of period	340,702	192,260
Supplemental Cash Flow Information:
Purchases of property, plant and equipment in accrued liabilities and accounts payable at the end of the period	13,841	2,425
Equity consideration related to the acquisition of KMG Chemicals, Inc	0	$ 331,048
Cash paid during the period for lease liabilities	3,825
Right of use asset obtained in exchange for lease liabilities	$ 3,334

CONSOLIDATED STATEMENT OF CHANG

CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Capital In Excess of Par	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balance at beginning of period at Sep. 30, 2018	$ 666,692	$ 36	$ 622,498	$ 471,673	$ 4,539	$ (432,054)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	8,170		8,170
Repurchases of common stock - other, at cost	(4,001)					(4,001)
Exercise of stock options	3,097		3,097
Issuance of Cabot Microelectronics restricted stock under Deposit Share Program	75		75
Issuance of common stock in connection with acquisition of KMG Chemicals, Inc.	331,048	3	331,045
Net income	13,443			13,443
Dividends	(11,598)			(11,598)
Foreign currency translation adjustment	2,425				2,425
Minimum pension liability adjustment	(251)				(251)
Balance at end of period at Dec. 31, 2018	1,008,167	39	964,885	472,585	6,713	(436,055)
Balance at beginning of period at Sep. 30, 2018	666,692	36	622,498	471,673	4,539	(432,054)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	40,580
Foreign currency translation adjustment	1,433
Minimum pension liability adjustment	0
Cash flow hedges	(6,474)
Balance at end of period at Mar. 31, 2019	1,025,867	39	975,612	487,467	(502)	(436,749)
Balance at beginning of period at Dec. 31, 2018	1,008,167	39	964,885	472,585	6,713	(436,055)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	3,538		3,538
Repurchases of common stock - other, at cost	(694)					(694)
Exercise of stock options	5,080		5,080
Issuance of Cabot Microelectronics stock under Employee Stock Purchase Plan	2,109		2,109
Net income	27,137			27,137
Dividends	(12,255)			(12,255)
Foreign currency translation adjustment	(992)				(992)
Interest rate swap	(6,474)				(6,474)
Minimum pension liability adjustment	251				251
Cash flow hedges	(6,474)
Balance at end of period at Mar. 31, 2019	1,025,867	39	975,612	487,467	(502)	(436,749)
Balance at beginning of period at Sep. 30, 2019	980,377	40	988,980	461,501	(23,238)	(446,906)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	4,763		4,763
Repurchases of common stock - other, at cost	(2,897)					(2,897)
Exercise of stock options	1,298		1,298
Issuance of Cabot Microelectronics restricted stock under Deposit Share Program	150		150
Net income	38,549			38,549
Dividends	(12,351)			(12,351)
Effect of the adoption of the stranded tax effect accounting standards	0			488	(488)
Foreign currency translation adjustment	15,851				15,851
Cash flow hedges	4,259				4,259
Balance at end of period at Dec. 31, 2019	1,029,999	40	995,191	488,187	(3,616)	(449,803)
Balance at beginning of period at Sep. 30, 2019	980,377	40	988,980	461,501	(23,238)	(446,906)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	71,448
Foreign currency translation adjustment	(3,874)
Minimum pension liability adjustment	0
Cash flow hedges	(13,048)
Balance at end of period at Mar. 31, 2020	1,009,410	40	1,008,311	508,126	(40,648)	(466,419)
Balance at beginning of period at Dec. 31, 2019	1,029,999	40	995,191	488,187	(3,616)	(449,803)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	4,234		4,234
Repurchases of common stock under Share Repurchase Program, at cost	(16,414)					(16,414)
Repurchases of common stock - other, at cost	(202)					(202)
Exercise of stock options	6,350		6,350
Issuance of Cabot Microelectronics stock under Employee Stock Purchase Plan	2,536		2,536
Net income	32,899			32,899
Dividends	(12,960)			(12,960)
Foreign currency translation adjustment	(19,725)				(19,725)
Minimum pension liability adjustment	0
Cash flow hedges	(17,307)				(17,307)
Balance at end of period at Mar. 31, 2020	$ 1,009,410	$ 40	$ 1,008,311	$ 508,126	$ (40,648)	$ (466,419)

CONSOLIDATED STATEMENT OF CHA_2

CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividends (in dollars per share)	$ 0.44	$ 0.42	$ 0.42	$ 0.40

BACKGROUND AND BASIS OF PRESENT

BACKGROUND AND BASIS OF PRESENTATION	6 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BACKGROUND AND BASIS OF PRESENTATION	BACKGROUND AND BASIS OF PRESENTATION Cabot Microelectronics Corporation (“Cabot Microelectronics”, “the Company”, “us”, “we”, or “our”) is a leading global supplier of consumable materials to semiconductor manufacturers and pipeline companies. The Company's products play a critical role in the production of advanced semiconductor devices, helping to enable the manufacture of smaller, faster and more complex devices by its customers. On November 15, 2018 (the “Acquisition Date”), we completed our acquisition of KMG Chemicals, Inc. (“KMG”), which produces and distributes specialty chemicals and performance materials for the semiconductor industry, pipeline and adjacent industries, and industrial wood preservation industry (the “Acquisition”). The Acquisition extended and strengthened our position as one of the leading suppliers of consumable materials to the semiconductor industry and expanded our portfolio with the addition of KMG’s businesses, which we believe enables us to be a leading global provider of performance materials to pipeline operators. The Consolidated Financial Statements included in this Report on Form 10-Q include the financial results of KMG from the Acquisition Date. Since the Acquisition, we now operate our business within two reportable segments: Electronic Materials and Performance Materials. The Electronic Materials segment consists of our heritage CMP slurries and polishing pads businesses, as well as the KMG electronic chemicals business. The Performance Materials segment includes KMG’s heritage pipeline performance and wood treatment businesses, and our heritage QED business. For additional information, refer to Item 1 of Part I of our Annual Report on Form 10-K for the fiscal year ended September 30, 2019. The unaudited Consolidated Financial Statements have been prepared by Cabot Microelectronics pursuant to the rules of the Securities and Exchange Commission (SEC) and accounting principles generally accepted in the United States of America (U.S. GAAP). In the opinion of management, these unaudited Consolidated Financial Statements include all adjustments, consisting of normal recurring adjustments, necessary for the fair statement of Cabot Microelectronics’ financial position as of March 31, 2020, cash flows for the six months ended March 31, 2020 and March 31, 2019, and results of operations for the three and six months ended March 31, 2020 and March 31, 2019. The Consolidated Balance Sheets as of September 30, 2019 were derived from audited financial statements. The results of operations for the three and six months ended March 31, 2020 may not be indicative of results to be expected for future periods, including the fiscal year ending September 30, 2020. This Report on Form 10-Q does not contain all of the footnote disclosures from our annual financial statements and should be read in conjunction with the Consolidated Financial Statements and related notes thereto included in our Annual Report on Form 10-K for the fiscal year ended September 30, 2019. The Consolidated Financial Statements include the accounts of Cabot Microelectronics and its subsidiaries. All intercompany transactions and balances between the companies have been eliminated as of March 31, 2020. USE OF ESTIMATES The preparation of financial statements and related disclosures in conformity with U.S. GAAP requires management to make judgments, assumptions and estimates that affect the amounts reported in the consolidated financial statements and accompanying notes. The accounting estimates that require management's most challenging and subjective judgments include, but are not limited to, those estimates related to impairment of long-lived assets, business combinations, asset retirement obligations, goodwill, other intangible assets, income taxes and contingencies. We base our estimates on historical experience, current conditions and on various other assumptions that we believe are reasonable under the circumstances. However, future events are subject to change and estimates and judgments routinely require adjustment. Actual results may differ from these estimates under different assumptions or conditions.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS	6 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS Significant Accounting Policies and Estimates There have been no material changes, except for those disclosed below, made to the Company’s significant accounting policies disclosed in Note 2 of "Notes to the Consolidated Financial Statements" included in Item 8 of Part II of our Annual Report on Form 10-K for the fiscal year ended September 30, 2019. In February 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-02, “Leases” (ASC 842) to change the criteria for recognizing leasing transactions. The provisions of this guidance require a lessee to recognize a right of use asset and a corresponding lease liability for operating leases. Under this guidance, rental expense for operating leases, continues to be recognized on a straight-line basis over the non-cancelable lease term. As of October 1, 2019, the Company began applying the provisions of this standard prospectively for all lease transactions as of and after the effective date. Upon adoption, the Company recorded a lease liability of $30,881 and a right of use asset of $30,115. The difference between the right of use asset and lease liability primarily relates to deferred rent recorded prior to adoption. The new guidance did not have a material impact on our results of operations or cash flows for the three and six months ended March 31, 2020. Refer to Note 11 of this Report on Form 10-Q for additional information regarding the Company’s lease transactions. In February 2018, the FASB issued ASU No. 2018-02 “Income Statement – Reporting Comprehensive Income” (Topic 220). The amendments in this standard allow for an optional one-time reclassification of the stranded tax effects resulting from the change in the U.S. federal corporate income tax rate under the Tax Cuts and Jobs Act (the "Tax Act") from Accumulated other comprehensive income to Retained earnings. The Company adopted this standard effective October 1, 2019, which resulted in an increase of $488 to both Retained earnings and Accumulated other comprehensive loss. In June 2016, the FASB issued ASU No. 2016-13, “Measurement of Credit Losses on Financial Instruments” (Topic 326). The provisions of this standard require financial assets measured at amortized cost to be presented at the net amount expected to be collected. An allowance account would be established to present the net carrying value at the amount expected to be collected. ASU 2016-13 also provides that credit losses relating to available-for-sale debt securities should be recorded through an allowance for credit losses. The guidance was amended through various ASU's subsequent to ASU 2016-13, all of which will be effective for the Company beginning October 1, 2020. We are currently evaluating the impact of implementing this standard on our financial statements. In August 2018, the FASB issued ASU No. 2018-13 “Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement”. The ASU provides specific guidance on various disclosure requirements in Topic 820, including removal, modification and addition to current disclosure requirements. ASU 2018-13 will be effective for us beginning October 1, 2020. We are currently evaluating the impact of implementing this standard on our disclosures. In December 2019, the FASB issued ASU No. 2019-12 “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes”. The ASU was issued to simplify Topic 740 through improving consistency and removing certain exceptions to general principles. ASU 2019-12 will be effective for us beginning October 1, 2021, but early adoption is permitted. We are currently evaluating the impact of implementing this standard on our financial statements. In March 2020, the FASB issued ASU No. 2020-04 "Reference Rate Reform (Topic 848) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” The standard provides optional guidance for accounting for contracts, hedging relationships, and other transactions affected by the reference rate reform, if certain criteria are met. The provisions of this standard are available for election through December 31, 2022. We are currently evaluating the impact of the reference rate reform on our contracts and the resulting impact of adopting this standard on our financial statements.

REVENUE FROM CONTRACTS WITH CUS

REVENUE FROM CONTRACTS WITH CUSTOMERS	6 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
REVENUE FROM CONTRACTS WITH CUSTOMERS	REVENUE FROM CONTRACTS WITH CUSTOMERS Disaggregated Revenue The Company disaggregates revenue by product area and segment as it best depicts the nature and amount of the Company’s revenue. See Note 18 of this Report on Form 10-Q for more information. Contract Balances The following table provides information about contract liability balances: March 31, 2020 September 30, 2019 Contract liabilities (current) $ 7,293 $ 5,008 Contract liabilities (noncurrent) 1,580 1,130 At March 31, 2020, the current portion of contract liabilities of $7,293 is included in Accrued expenses, income taxes payable and other current liabilities, and the non-current portion of $1,580 is included in Other long-term liabilities in the Consolidated Balance Sheets. The amount of revenue recognized during the three and six months ended March 31, 2020 that was included in the opening current contract liability balances in our Performance Materials segment were $769 and $3,027, respectively. The amount of revenue recognized during the three and six months ended March 31, 2020 that was included in our opening contract liability balances in our Electronic Materials segment was not material. Transaction Price Allocated to Remaining Performance Obligations The table below discloses (1) the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for contracts with an original duration of greater than one year and (2) when the Company expects to recognize this revenue. Less Than 1 Year 1-3 Years Total Revenue expected to be recognized on contract liability amounts as of March 31, 2020 $ 1,182 $ 1,580 $ 2,762

BUSINESS COMBINATION

BUSINESS COMBINATION	6 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
BUSINESS COMBINATION	BUSINESS COMBINATION On the Acquisition Date, the Company completed its acquisition of 100% of the outstanding stock of KMG, which was a publicly-held company headquartered in Fort Worth, Texas. KMG specialized in producing, processing, and distributing electronic chemicals for the semiconductor industry and performance materials for the pipeline and adjacent industries, and industrial wood preservation industry. We acquired KMG to extend and strengthen our position as one of the leading suppliers of consumable materials to the semiconductor industry and to expand our portfolio with the addition of KMG’s performance materials businesses, which we believe enables us to become a leading global provider of performance materials to pipeline operators. The purchase consideration was $1,513,235, including consideration transferred of $1,536,452, less cash acquired of $23,217. The consideration was comprised of cash consideration to KMG common stockholders and equity award holders, stock consideration to KMG common stockholders and equity award holders, and cash consideration in the form of the retirement of KMG’s preexisting debt obligations. Under the terms of the definitive agreement to acquire KMG, each share of KMG common stock was converted into the right to receive $55.65 in cash and 0.2000 of a share of Cabot Microelectronics common stock. As a result, we issued 3,237,005 shares of our common stock to KMG’s common stockholders, with a stock price of $102.27 on the Acquisition Date. In connection with the Acquisition, we entered into a credit agreement which provided a seven Amount Total cash consideration paid for KMG outstanding common stock and equity awards $ 900,756 Cash provided to payoff KMG debt 304,648 Total cash consideration paid 1,205,404 Fair value of Cabot Microelectronics common stock issued for KMG outstanding common stock and equity awards 331,048 Total consideration transferred $ 1,536,452 The following table summarizes the allocation of fair values of assets acquired and liabilities assumed as of the Acquisition Date. Amount Cash $ 23,217 Accounts receivable 63,950 Inventories 68,087 Prepaid expenses and other current assets 14,694 Property, plant and equipment 147,170 Intangible assets 844,800 Other long-term assets 5,805 Accounts payable (28,835) Accrued expenses and other current liabilities (44,216) Deferred income taxes liabilities (156,474) Other long-term liabilities (15,080) Total identifiable net assets acquired 923,118 Goodwill 613,334 Total consideration transferred $ 1,536,452 The Acquisition was accounted for using the acquisition method of accounting. Tangible and identifiable intangible assets acquired and liabilities assumed are recorded at fair value as of the Acquisition Date. We believe that the information we used provides a reasonable basis for estimating the fair value of assets acquired and liabilities assumed. The Company finalized the purchase price allocation during the fourth quarter of fiscal 2019. During the first quarter of fiscal 2020, the Company made adjustments to the purchase price allocation to correct immaterial errors. The fair values of identifiable assets and liabilities acquired were developed with the assistance of a third-party valuation firm. The fair value of acquired property, plant and equipment is primarily valued at its “value-in-use.” The fair value of acquired identifiable intangible assets was determined using the “income approach” on an individual asset basis. The key assumptions used in the calculation of the discounted cash flows include projected revenue, operating expenses, discount rates terminal growth rates, and customer attrition rates. The valuations and the underlying assumptions have been deemed reasonable by the Company’s management. There are inherent uncertainties and management judgment required in these determinations. The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the Acquisition Date: Fair Value Estimated Useful Life Customer relationships - Flowchem $ 315,000 20 Customer relationships - Electronic chemicals 280,000 19 Customer relationships - all other 109,000 15-16 Technology and know-how 85,500 9-11 Trade name - Flowchem 46,000 Indefinite Trade name - all other 7,000 1-15 EPA product registration rights 2,300 15 Total intangible assets $ 844,800 Customer relationships represent the estimated fair value of the underlying relationships and agreements with KMG’s customers, and are being amortized on an accelerated basis in order for the expense to most accurately match the periods of highest cash flows attributable to the identified relationships. Technology and know-how represent the estimated fair value of KMG’s technology, processes and knowledge regarding its product offerings, and are being amortized on a straight-line basis. Trade names represent the estimated fair value of the brand and name recognition associated with the marketing of KMG’s product offerings and are being amortized on a straight-line basis, except for the Flowchem trade name, which we believe has an indefinite life. The intangible assets subject to amortization have a weighted average useful life of 17.9 years. For intangible assets related to the wood treatment business, the remaining useful lives were limited to the end of the calendar year 2021. As discussed in our Annual Report on Form 10-K for the fiscal year ended September 30, 2019, the Company recognized asset impairment charges of $67,372, net for the wood treatment asset group due to triggering events that occurred in the fourth quarter of fiscal 2019. The Company continues to monitor the wood treatment asset group for indicators of long-lived asset or goodwill impairment. As the Company approaches the announced closure date of the facilities and there are lower estimated future cash flows, there is a potential for further impairments of long-lived assets and goodwill absent a sale of the business. While the timing and amounts of any further impairments are unknown, they could be material to the Company’s Consolidated Balance Sheets and to the Consolidated Statements of Income, but they will not affect the Company’s reported Net cash provided by operating activities. Refer to Note 10 of "Notes to the Consolidated Financial Statements" included in Item 8 of Part II of our Annual Report on Form 10-K for the fiscal year ended September 30, 2019 for additional information. The excess of consideration transferred over the fair value of net assets acquired was recorded as goodwill, and is not deductible for income tax purposes. The goodwill is primarily attributable to anticipated revenue growth from the combined company product portfolio, expected synergies of the combined company, and the assembled workforce of KMG. The allocation of goodwill to each of the Electronic Materials and Performance Materials segments as a result of the Acquisition was $259,859 and $353,475, respectively. For the three and six months ended March 31, 2020, we recorded $2,285 and $5,050, respectively, in Acquisition and integration-related expenses, including professional fees and retention costs. These items are included within Selling, general and administrative in the Consolidated Statements of Income. KMG’s results of operations have been included in our unaudited Consolidated Statements of Income and Consolidated Statements of Comprehensive Income (Loss) from the Acquisition Date. Net sales of the acquired KMG businesses for the three and six months ended March 31, 2020 were $137,996 and $271,429, respectively. KMG’s Net income for the three and six months ended March 31, 2020 were $16,604 and $31,290, respectively, which include Acquisition-related costs of $117 and $323, respectively. Further, additional amortization and depreciation expense associated with recording KMG’s net assets at fair value decreased KMG’s Net income post-Acquisition. The following unaudited supplemental pro forma information summarizes the combined results of operations for Cabot Microelectronics and KMG as if the Acquisition had occurred on October 1, 2017. Three Months Ended Six Months Ended Revenue $ 265,391 $ 549,147 Net income 26,871 64,473 Earnings per share - basic 0.93 2.23 Earnings per share - diluted 0.91 2.19 The following costs are included in the three and six months ended March 31, 2019: • Non-recurring transaction costs of $621 and $1,436, respectively. • Non-recurring transaction-related employee costs, such as accelerated stock compensation expense, retention and severance expense of $51 and $154, respectively. The historical financial information has been adjusted by applying the Company’s accounting policies and giving effect to the pro forma adjustments, which consist of (i) amortization expense associated with identified intangible assets; (ii) depreciation of fixed asset step-up (for pre-Acquisition periods only); (iii) accretion of inventory step-up value; (iv) the elimination of Interest expense on pre-Acquisition KMG debt and replacement of Interest expense related to the Acquisition-related financing; (v) transaction-related costs; (vi) accelerated share-based compensation expense (pre-Acquisition periods only); (vii) retention and severance expense incurred as a direct result of the Acquisition; and (viii) an adjustment to tax-effect the aforementioned unaudited pro forma adjustments using an estimated weighted-average effective income tax rate of each entity and the jurisdictions to which the above adjustments relate. The pro forma consolidated results are not necessarily indicative of what the consolidated results actually would have been had the Acquisition been completed on October 1, 2017. The pro forma consolidated results do not purport to project future results of combined operations, nor do they reflect the expected realization of any revenue or cost synergies associated with the Acquisition.

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	6 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	FAIR VALUE OF FINANCIAL INSTRUMENTS Fair value is defined as the price that would be received from the sale of an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The FASB established a three-level hierarchy for disclosure based on the extent and level of judgment used to estimate fair value. Level 1 inputs consist of valuations based on quoted market prices in active markets for identical assets or liabilities. Level 2 inputs consist of valuations based on quoted prices for similar assets or liabilities, quoted prices for identical assets or liabilities in an inactive market, or other observable inputs. Level 3 inputs consist of valuations based on unobservable inputs that are supported by little or no market activity. The following table presents financial instruments, other than debt, that we measured at fair value on a recurring basis at March 31, 2020 and September 30, 2019. See Note 10 of this Report on Form 10-Q for a detailed discussion of our debt. We have classified the following assets and liabilities in accordance with the fair value hierarchy set forth in the applicable standards. In instances where the inputs used to measure the fair value of an asset fall into more than one level of the hierarchy, we have classified them based on the lowest-level input that is significant to the determination of the fair value. March 31, 2020 Level 1 Level 2 Level 3 Total Fair Value Assets: Cash and cash equivalents $ 340,702 $ — $ — $ 340,702 Other long-term investments 1,036 — — 1,036 Total assets $ 341,738 $ — $ — $ 341,738 Liabilities: Derivative financial instruments — 41,452 — 41,452 Total liabilities $ — $ 41,452 $ — $ 41,452 September 30, 2019 Level 1 Level 2 Level 3 Total Fair Value Assets: Cash and cash equivalents $ 188,495 $ — $ — $ 188,495 Other long-term investments 980 — — 980 Total assets $ 189,475 $ — $ — $ 189,475 Liabilities: Derivative financial instruments — 24,244 — 24,244 Total liabilities $ — $ 24,244 $ — $ 24,244 Our cash and cash equivalents consist of various bank accounts used to support our operations and investments in institutional money-market funds that are traded in active markets. We invest only in AAA-rated, prime institutional money market funds, comprised of high quality, short-term fixed income securities. Our other long-term investments represent the fair value of investments under the Cabot Microelectronics Supplemental Employee Retirement Plan (SERP), which is a non-qualified supplemental savings plan. The fair value of the investments is determined through quoted market prices within actively traded markets. Although the investments are allocated to individual participants and investment decisions are made solely by those participants, the SERP is a non-qualified plan. Consequently, the Company owns the assets and the related offsetting liability for disbursement until such time as a participant makes a qualifying withdrawal. The long-term asset was adjusted to $1,036 in the second quarter of fiscal 2020 to reflect its fair value as of March 31, 2020. Our derivative financial instruments include foreign exchange contracts and an interest rate swap contract. During the second quarter of fiscal 2019, we entered into a floating-to-fixed interest rate swap contract to hedge the variability in LIBOR-based interest payments on a portion of our outstanding variable rate debt. The fair value of our derivative instruments is estimated using standard valuation models and market-based observable inputs over the contractual term, including one-month LIBOR-based yield curves for the interest rate swap, and forward rates and/or the Overnight Index Swap (OIS) curve for forward foreign exchange contracts, among others. We consider the risk of nonperformance, including counterparty credit risk, in the calculation of the fair value of derivative financial instruments. See Note 12 of this Report on Form 10-Q for more information on our use of derivative financial instruments.

INVENTORIES

INVENTORIES	6 Months Ended
	Mar. 31, 2020
Inventory Disclosure [Abstract]
INVENTORIES	INVENTORIES Inventories consisted of the following: March 31, 2020 September 30, 2019 Raw materials $ 63,296 $ 60,157 Work in process 17,915 12,940 Finished goods 76,661 72,181 Total $ 157,872 $ 145,278

GOODWILL AND OTHER INTANGIBLE A

GOODWILL AND OTHER INTANGIBLE ASSETS	6 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS	GOODWILL AND OTHER INTANGIBLE ASSETS Goodwill activity for each of the Company’s reportable segments, which carry goodwill, Electronic Materials and Performance Materials, for the six months ended March 31, 2020. Electronic Materials Performance Materials Total Balance at September 30, 2019 $ 352,797 $ 357,274 $ 710,071 Foreign currency translation impact 465 (1,918) (1,453) Other — 1,205 1,205 Balance at March 31, 2020 $ 353,262 $ 356,561 $ 709,823 The components of other intangible assets are: March 31, 2020 September 30, 2019 Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Other intangible assets subject to amortization: Product technology, trade secrets and know-how $ 121,579 $ 42,230 $ 123,948 $ 37,993 Acquired patents and licenses 9,023 8,558 9,023 8,397 Customer relationships, trade names, and distribution rights 685,061 103,386 684,764 64,471 Total other intangible assets subject to amortization 815,663 154,174 817,735 110,861 Other intangible assets not subject to amortization: Other indefinite-lived intangibles* 47,170 47,170 Total other intangible assets not subject to amortization 47,170 47,170 Total other intangible assets $ 862,833 $ 154,174 $ 864,905 $ 110,861 *Other indefinite-lived intangible assets not subject to amortization consist primarily of trade names. Amortization expense was $22,014 and $43,378 for the three and six months ended March 31, 2020, respectively, and was $16,960 and $26,318 for the three and six months ended March 31, 2019, respectively. Estimated future amortization expense for the five succeeding fiscal years is as follows: Fiscal Year Estimated Remainder of 2020 $ 42,429 2021 90,474 2022 80,974 2023 68,480 2024 60,528 Goodwill and indefinite-lived intangible assets are tested for impairment annually in the fourth quarter of our fiscal year or more frequently if indicators of potential impairment exist, using a fair-value-based approach. The recoverability of goodwill is measured at the reporting unit level, which is defined as either an operating segment or one level below an operating segment. An entity has the option to assess the fair value of a reporting unit either using a qualitative analysis ("step zero") or a quantitative analysis ("step one"). Similarly, an entity has the option to use a step zero or a step one approach to determine the recoverability of indefinite-lived intangible assets. In fiscal year 2019, we chose to use a step one analysis for both goodwill impairment and for indefinite-lived intangible asset impairment, with the exception of our CMP slurries and QED reporting units, for which we chose to use a step zero analysis for fiscal year 2019.

OTHER LONG-TERM ASSETS

OTHER LONG-TERM ASSETS	6 Months Ended
	Mar. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
OTHER LONG-TERM ASSETS	OTHER LONG-TERM ASSETS Other long-term assets consisted of the following: March 31, 2020 September 30, 2019 Long-term right of use asset $ 29,715 $ — Long-term contract assets 3,776 1,164 Long-term SERP investment 1,036 980 Prepaid unamortized debt issuance cost - revolver 623 709 Other long-term assets 2,574 2,858 Total $ 37,724 $ 5,711

ACCRUED EXPENSES, INCOME TAXES

ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES	6 Months Ended
	Mar. 31, 2020
Payables and Accruals [Abstract]
ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES	ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES Accrued expenses, income taxes payable and other current liabilities consisted of the following: March 31, 2020 September 30, 2019 Accrued compensation $ 33,833 $ 33,809 Income taxes payable 16,470 15,725 Dividends payable 13,510 12,953 Interest rate swap liability 12,410 5,351 Contract liabilities (current) 7,293 5,008 Current portion of operating lease liability 5,498 — Taxes, other than income taxes 5,330 6,281 Goods and services received, not yet invoiced 3,950 3,075 KMG - Bernuth warehouse fire-related (See Note 13) — 7,998 Accrued interest — 3,739 Other 11,095 9,679 Total $ 109,389 $ 103,618

DEBT

DEBT	6 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
DEBT	DEBT In connection with the Acquisition, we entered into a seven The Term Loan Facility matures on November 15, 2025, the seven five At March 31, 2020, the fair value of the Term Loan Facility, using level 2 inputs, approximated its carrying value of $941,687 as the loans bears a floating market rate of interest. As of March 31, 2020, $10,650 of the Term Loan Facility was classified as short-term, and $16,420 of debt issuance costs related to our Term Loan Facility were presented as a reduction of long-term debt. On March 13, 2020, the Company drew $150.0 million under the Revolving Credit Facility as a precautionary measure in order to increase its cash position and preserve financial flexibility in light of uncertain global economic conditions resulting from the Pandemic. Prior to this, the Company had not drawn any amounts under the Revolving Credit Facility. As of March 31, 2020, $150.0 million was outstanding under the Revolving Credit Facility, and our available credit under the Revolving Credit Facility was $50.0 million, including our letter of credit sub-facility. Borrowings under the Revolving Credit Facility are classified as short-term debt. Proceeds from the Revolving Credit Facility are included in Cash and cash equivalents in the Company's Consolidated Balance Sheet as of March 31, 2020. Due to the short-term nature of the borrowing under the Revolving Credit Facility, its carrying value approximates fair value. During the first quarter of fiscal year 2020, the Company amended the Credit Agreement to reduce the interest rate on term loan borrowings. The amended Term Loan Facility and amended Credit Facilities are referred to as "Amended Term Loan Facility" and "Amended Credit Facilities", respectively. Borrowings under the Amended Credit Facilities bear interest at a rate per annum equal to, at the Company’s option, either (a) a LIBOR, subject to a 0.00% floor, or (b) a base rate, in each case plus an applicable margin of, in the case of borrowings under the Amended Term Loan Facility, 2.00% for LIBOR loans and 1.00% for base rate loans and, in the case of borrowings under the Revolving Credit Facility, initially, 1.50% for LIBOR loans and 0.50% for base rate loans. The applicable margin for borrowings under the Revolving Credit Facility varies depending on the Company’s first lien secured net leverage ratio. The Company is also required to pay a commitment fee currently equal to 0.25% per annum to the lenders under the Revolving Credit Facility in respect of the unutilized commitments thereunder. The commitment fee under the Revolving Credit Facility varies depending on the Company’s first lien secured net leverage ratio. In the second quarter of fiscal 2019, we entered into a floating-to-fixed interest rate swap contract to hedge the variability in our LIBOR-based interest payments on approximately 70% of our Term Loan Facility balance. See Note 12 of this Report on Form 10-Q for additional information. Principal repayments of the Term Loan Facility are generally made on the last calendar day of each quarter if that day is considered a business day. As of March 31, 2020, scheduled principal repayments of the Term Loan were: Fiscal Year Principal Repayments Remainder of 2020 $ 5,325 2021 10,650 2022 10,650 2023 10,650 2024 10,650 Greater than 5 years 893,762 Total $ 941,687

LEASES

LEASES	6 Months Ended
	Mar. 31, 2020
Leases [Abstract]
LEASES	LEASES Effective October 1, 2019, the Company adopted the new lease accounting guidance which requires the recognition of a right of use asset and a corresponding lease liability for operating leases. As part of the adoption, the Company elected to apply provisions of the guidance to operating leases with terms of more than twelve months for all lease classes except for real estate leases for which the guidance is applied to all leases. Additionally, the Company elected to account for non-lease components and lease components together as a single lease component for all asset classes. The Company’s lease transactions primarily consist of leases for facilities, equipment and vehicles under operating leases. The Company does not have any material finance leases. The weighted average remaining lease term for operating leases included in the lease liability was approximately seven years, as of March 31, 2020. Certain of the Company’s leases have an option to extend the lease term and the renewal period is included in determining the lease term for leases where the renewal option is reasonably certain to be exercised. Total lease cost for the Company for the three months ended March 31, 2020 was $2,320, which included $1,903 related to operating lease cost and $417 related to short-term and variable lease costs. Total lease cost for the Company for the six months ended March 31, 2020 was $4,806, which included $3,886 related to operating lease cost and $920 related to short-term and variable lease costs. The right of use asset related to operating leases as of March 31, 2020 was $29,715 and was recorded in Other long-term assets. As of March 31, 2020, the current portion of the lease liability for operating leases was $5,498 and was included in Accrued expenses, income taxes payable and other current liabilities, and the long-term portion was $25,390 and was included in Other long-term liabilities. The weighted average discount rate for operating leases as of March 31, 2020 was 3.02%, and was determined based on the secured incremental borrowing rate of the Company and its subsidiaries as the implicit rate is not readily determinable. Future maturities of operating lease liabilities for the years ended September 30 are as follows: Fiscal Year Amount Remainder of 2020 $ 3,356 2021 5,538 2022 5,185 2023 4,728 2024 4,068 2025 and future years 11,544 Total future lease payments 34,419 Less: Imputed interest 3,531 Operating lease liability 30,888 Less: Current portion of operating lease liability 5,498 Long-term portion of operating lease liability $ 25,390 As of September 30, 2019, minimum lease payments under operating leases with noncancelable terms in excess of one are as follows: Fiscal Year Amount 2020 $ 6,984 2021 4,941 2022 4,291 2023 4,122 2024 3,710 Thereafter 12,010 Total future minimum lease payments $ 36,058

DERIVATIVE FINANCIAL INSTRUMENT

DERIVATIVE FINANCIAL INSTRUMENTS	6 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE FINANCIAL INSTRUMENTS	DERIVATIVE FINANCIAL INSTRUMENTS We are exposed to various market risks, including risks associated with interest rates and foreign currency exchange rates. We enter into certain derivative transactions to mitigate the volatility associated with these exposures. We have policies in place that define acceptable instrument types we may enter into and we have established controls to limit our market risk exposure. We do not use derivative financial instruments for trading or speculative purposes. In addition, all derivatives, whether designated in hedging relationships or not, are required to be recorded on the Consolidated Balance Sheets at fair value on a gross basis. Cash Flow Hedges - Interest Rate Swap Contract During the second quarter of fiscal 2019, we entered into a floating-to-fixed interest rate swap contract to hedge the variability in LIBOR-based interest payments on a portion of our outstanding variable rate debt. As of March 31, 2020, the notional value of the interest rate swap was $652,000. This value is scheduled to decrease bi-annually and will expire on January 31, 2024. We have designated this swap contract as a cash flow hedge pursuant to ASC 815, "Derivatives and Hedging". Based on certain quantitative and qualitative assessments, we have determined that the hedge is highly effective and qualifies for hedge accounting. Accordingly, unrealized gains and losses on the hedge are recorded in other comprehensive income. Realized gains and losses are recorded on the same financial statement line as the hedged item, which is Interest expense. Foreign Currency Contracts Not Designated as Hedges On a regular basis, we enter into forward foreign exchange contracts in an effort to mitigate the risks associated with currency fluctuations on certain foreign currency balance sheet exposures. These foreign exchange contracts do not qualify for hedge accounting; therefore, the gains and losses resulting from the impact of currency exchange rate movements on our forward foreign exchange contracts are recognized as Other income (expense), net in the accompanying Consolidated Statements of Income in the period in which the exchange rates change. As of March 31, 2020 and September 30, 2019, the notional amounts of the forward contracts we held to purchase U.S. dollars in exchange for foreign currencies were $5,746 and $6,239, respectively, and the notional amounts of forward contracts we held to sell U.S. dollars in exchange for foreign currencies were $24,800 and $24,270, respectively. The fair value of our derivative instruments included in the Consolidated Balance Sheets, which was determined using level 2 inputs, was as follows: Derivative Assets Derivative Liabilities Consolidated Balance Sheet Location March 31, 2020 September 30, 2019 March 31, 2020 September 30, 2019 Derivatives designated as hedging instruments Interest rate swap contract Accrued expenses, income taxes payable and other current liabilities $ — $ — $ 12,410 $ 5,351 Other long-term liabilities $ — $ — $ 28,585 $ 18,841 Derivatives not designated as hedging instruments Foreign exchange contracts Accrued expenses, income taxes payable and other current liabilities $ — $ — $ 458 $ 52 The following table summarizes the effect of our derivative instruments on our Consolidated Statements of Income for the three and six months ended March 31, 2020 and 2019: Gain (Loss) Recognized in Statement of Income Three Months Ended March 31, Six Months Ended March 31, Statement of Income Location 2020 2019 2020 2019 Derivatives not designated as hedging instruments Foreign exchange contracts Other income (expense), net $ (268) $ (348) $ (262) $ (38) The interest rate swap contract has been deemed to be effective, and we realized a loss of $1,366 and $2,537 in Interest expense during the three and six months ended March 31, 2020, respectively. We recorded an unrealized loss of $18,367 and $15,017, net of tax, in Accumulated other comprehensive income during the three and six months ended March 31, 2020, respectively, for this interest rate swap. As of March 31, 2020, during the next 12 months, we expect approximately $12,410 to be reclassified from Accumulated other comprehensive (loss) income into Interest expense related to our interest rate swap based on projected rates of the LIBOR forward curve as of March 31, 2020.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	6 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES LEGAL PROCEEDINGS AND OTHER CONTINGENCIES We periodically become a party to legal proceedings, arbitrations, and regulatory proceedings (“contingencies”) arising in the ordinary course of our business operations. The ultimate resolution of these contingencies is subject to significant uncertainty, and should we fail to prevail in any of them or should several of them be resolved against us in the same reporting period, these matters could, individually or in the aggregate, be material to our consolidated financial statements. One of these contingencies, related to Star Lake Canal, which we assumed in connection with the Acquisition, is discussed below. The ultimate outcome of these matters, however, cannot be determined at this time, nor can the amount of any potential loss be reasonably estimated, and as a result except where indicated no amounts have been recorded in our consolidated financial statements. The Company records legal costs associated with loss contingencies as expenses in the period in which they are incurred. On May 31, 2019, a fire occurred at the warehouse of the facility of KMG’s subsidiary, KMG-Bernuth, in Tuscaloosa, Alabama, which processes pentachlorophenol ("penta") for sale to customers in the United States and Canada. The warehouse fire, which we believe originated from non-hazardous waste materials temporarily stored in the warehouse for recycling purposes, caused no injuries and was extinguished in less than an hour. Company personnel investigated the incident, and KMG-Bernuth commenced cleanup with oversight from certain local, state and federal authorities. The carrying value of the warehouse and the affected inventory are not material. Applying the accounting guidance under ASC 410-30, Environmental Obligations and ASC 450, Contingencies, we determined that since we have environmental obligations as of the date of the fire, costs for the fire waste cleanup and disposal should be recognized to the extent they are probable and reasonably estimable. We recorded expense of $9,494 in fiscal year 2019 and $593 during the six months ended March 31, 2020. These disposal costs were charged to Cost of sales. Although we believe we have completed cleanup efforts related to the fire incident, there are potential additional disposal and other costs that cannot be reasonably estimated as of this time related to materials in the warehouse impacted by the incident due to the nature of federally-regulated penta-related requirements. The fire waste cleanup and disposal costs were significant due to these requirements, and we may incur additional significant disposal costs related to the impacted warehouse materials. We will continue to update the estimated losses as new information becomes available. In addition, we are working with our insurance carriers on possible recovery of losses and costs, but at this point we cannot reasonably estimate whether we will receive any potential insurance recoveries, or if so, the amount of any such recoveries. As such, no insurance recoveries have been recognized as of March 31, 2020. Separately, in 2014, prior to the Acquisition, the United States Environmental Protection Agency (“EPA”) had notified KMG-Bernuth, that the EPA considered it to be a potentially responsible party under the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended (“CERCLA”) by virtue of its relationship with certain alleged predecessor companies, including Idacon, Inc (f/k/a Sonford Chemical Company) in connection with the Star Lake Canal Superfund Site near Beaumont, Texas. The EPA has estimated that the remediation will cost approximately $22.0 million. KMG-Bernuth and approximately seven other parties entered into an agreement with the EPA in September 2016 to complete a remedial design phase of the remediation of the site. The remediation work will be performed under a separate future agreement. Although KMG-Bernuth has not conceded liability, a reserve in connection with the remedial design was established, and as of March 31, 2020, the reserve remaining was $553. We also may face other governmental or third-party claims, or otherwise incur costs, relating to cleanup of, or for injuries resulting from, contamination at sites associated with this or other past and present operations. We accrue for environmental liabilities when a determination can be made that they are probable and reasonably estimable. Other than as described herein, we are not involved in any legal proceedings that we believe could have a material impact on our consolidated financial position, results of operations or cash flows. In addition, our Company is subject to extensive federal, state and local laws, regulations and ordinances in the United States and in other countries. These regulatory requirements relate to the use, generation, storage, handling, emission, transportation and discharge of certain hazardous materials, substances and waste into the environment. The Company, including its KMG entities, manage Environmental, Health and Safety (“EHS”) matters related to protection of the environment and human health, the cleanup of contaminated sites, the treatment, storage and disposal of wastes, and the emission of substances into the air or waterways, among other EHS concerns. Governmental authorities can enforce compliance with their regulations, and violators may be subject to fines, injunctions or both. The Company devotes significant financial resources to compliance, including costs for ongoing compliance. Certain licenses, permits and product registrations are required for the Company’s products and operations in the United States, Mexico and other countries in which it does business. The licenses, permits and product registrations are subject to revocation, modification and renewal by governmental authorities. In the United States in particular, producers and distributors of penta, which is a product manufactured and sold by KMG-Bernuth as part of the wood treatment business, are subject to registration and notification requirements under the Federal Insecticide, Fungicide and Rodenticide Act (“FIFRA”) and comparable state law in order to sell this product in the United States. Compliance with these requirements may have a significant effect on our business, financial condition and results of operations. We are subject to contingencies, including litigation relating to EHS laws and regulations, commercial disputes and other matters. Certain of these contingencies are discussed above and below. The ultimate resolution of these contingencies is subject to significant uncertainty, and should we fail to prevail in any of them or should several of them be resolved against us in the same reporting period, these matters could, individually or in the aggregate, be material to the consolidated financial statements. The ultimate outcome of these matters cannot be determined at this time, nor can the amount of any potential loss be reasonably estimated, and as a result except where indicated no amounts have been recorded in our consolidated financial statements. INDEMNIFICATION In the normal course of business, we are a party to a variety of agreements pursuant to which we may be obligated to indemnify the other party with respect to certain matters. Generally, these obligations arise in the context of agreements entered into by us, under which we customarily agree to hold the other party harmless against losses arising from items such as a breach of certain representations and covenants including title to assets sold, certain intellectual property rights and certain environmental matters. These terms are common in the industries in which we conduct business. In each of these circumstances, payment by us is subject to certain monetary and other limitations and is conditioned on the other party making an adverse claim pursuant to the procedures specified in the particular agreement, which typically allow us to challenge the other party's claims. We evaluate estimated losses for such indemnifications under the accounting standards related to contingencies and guarantees. We consider such factors as the degree of probability of an unfavorable outcome and the ability to make a reasonable estimate of the amount of loss. To date, we have not experienced material costs as a result of such obligations and, as of March 31, 2020, have not recorded any liabilities related to such indemnifications in our financial statements as we do not believe the likelihood of such obligations is probable. Refer to Note 20 of “Notes to the Consolidated Financial Statements” included in Item 8 of Part II of our Annual Report on Form 10-K for the fiscal year ended September 30, 2019, for additional information regarding commitments and contingencies. POSTRETIREMENT OBLIGATIONS IN FOREIGN JURISDICTIONS We have defined benefit plans covering employees in certain foreign jurisdictions as required by local law which are unfunded. Net service costs are recorded as fringe benefit expense under Cost of sales and Operating expenses, and all other costs are recorded in the Other income (expense), net in our Consolidated Statements of Income. The projected benefit obligations and accumulated benefit obligations under all such unfunded plans are updated annually during the fourth quarter of the fiscal year. Benefit payments under all such unfunded plans to be paid over the next ten years are expected to be approximately $7,872. For more information regarding these plans, refer to Note 20 of “Notes to the Consolidated Financial Statements” included in Item 8 of Part II of our Annual Report on Form 10-K for the fiscal year ended September 30, 2019. PURCHASE OBLIGATIONS

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	6 Months Ended
	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) The table below summarizes the components of Accumulated other comprehensive income (loss) (AOCI), net of Provision for income taxes/(benefit), for the three and six months ended March 31, 2020 and 2019: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Beginning Balance $ (3,616) $ 6,713 $ (23,238) $ 4,539 Foreign currency translation adjustment (19,752) (1,621) (3,935) 1,412 Income taxes 27 629 61 21 Foreign currency translation adjustment, net of tax (19,725) (992) (3,874) 1,433 Change in pension and other postretirement — 251 — — Unrealized gain loss on cash flow hedges: Change in fair value (23,655) (8,352) (19,340) (8,352) Reclassification adjustment into earnings 1,366 (1) 2,537 (1) Income taxes 4,982 1,879 3,755 1,879 Unrealized loss on cash flow hedges, net of tax (17,307) (6,474) (13,048) (6,474) Effect of the adoption of the stranded tax effect accounting standards — — (497) — Income taxes — — 9 — Effect of the adoption of the stranded tax effect accounting standards, net of tax — — (488) — Net Change (37,032) (7,215) (17,410) (5,041) Ending Balance $ (40,648) $ (502) $ (40,648) $ (502) The before tax amount reclassified from AOCI to Net income during the three and six months ended March 31, 2020 and 2019, related to cash flow hedges, were recorded as Interest expense on our Consolidated Statements of Income. During the first quarter of fiscal 2020, the Company adopted ASU No. 2018-02 regarding the reclassification of stranded tax effects resulting from the change in the U.S. federal corporate income tax rate under the Tax Act and as a result, we reclassified $488 of stranded tax effects from Accumulated other comprehensive income to Retained earnings.

SHARE-BASED COMPENSATION PLANS

SHARE-BASED COMPENSATION PLANS	6 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
SHARE-BASED COMPENSATION PLANS	SHARE-BASED COMPENSATION PLANSWe issue share-based awards under the following programs: our Cabot Microelectronics Corporation 2012 Omnibus Incentive Plan, as amended effective March 7, 2017 (OIP); our Cabot Microelectronics Corporation 2007 Employee Stock Purchase Plan, as Amended and Restated January 1, 2010 (ESPP); and, pursuant to the OIP, our Directors' Deferred Compensation Plan, as amended September 23, 2008 (DDCP), and our 2001 Executive Officer Deposit Share Program (DSP). In March 2017, our stockholders approved the material terms of performance-based awards under the OIP for purposes of complying with Section 162(m) of the Internal Revenue Code of 1986, as amended. For additional information regarding these programs, refer to Note 16 of "Notes to the Consolidated Financial Statements" included in Item 8 of Part II of our Annual Report on Form 10-K for the fiscal year ended September 30, 2019. We record share-based compensation expense for all share-based awards, including stock option grants, and restricted stock, restricted stock unit and performance share unit ("PSU") awards, and employee stock purchase plan purchases. We calculate share-based compensation expense using the straight-line approach based on awards ultimately expected to vest, which requires the use of an estimated forfeiture rate. Our estimated forfeiture rate is primarily based on historical experience, but may be revised in future periods if actual forfeitures differ from the estimate. We use the Black-Scholes option-pricing model to estimate the grant date fair value of our stock options and employee stock purchase plan purchases. This model requires the input of highly subjective assumptions, including the price volatility of the underlying stock, the expected term of our stock options, expected dividend yield and the risk-free interest rate. We estimate the expected volatility of our stock options based on a combination of our stock's historical volatility and the implied volatilities from actively-traded options on our stock. We calculate the expected term of our stock options using historical stock option exercise data, and for stock option grants made prior to December 2017, we have added a slight premium to this expected term for employees who meet the definition of retirement-eligible pursuant to their stock option grants during the contractual term of the grant. As of December 2017, the provisions of stock option grants and restricted stock unit awards stated that, except in certain circumstances including termination for cause, once an employee meets the retirement eligibility requirements, any remaining unvested share-based awards will continue to vest regardless of termination of service. Consequently, the requisite service period for the award is satisfied upon retirement eligibility. Therefore, we record the total share-based compensation expense upon award for those employees who have met the retirement eligibility at the grant date. The expected dividend yield represents our annualized dividend in dollars divided by the stock price on the date of grant. The risk-free interest rate is derived from the U.S. Treasury yield curve in effect at the time of grant. The PSUs that have been awarded may be subject to downward or upward adjustment depending on the total shareholder return achieved by the Company during the particular performance period related to the PSUs, relative to the total shareholder return of an established market index. We use a third-party service provider to estimate the fair value of the PSUs at grant date by using a Monte Carlo simulation model. This model simulates the stock price movements of the Company and Index constituents using certain assumptions, including the stock price of the Company and index constituents, the risk-free interest rate and stock price volatility. Subsequent to the Acquisition, the performance metrics of the PSUs awarded in December 2017 were modified to reflect the performance metrics expected due to the Acquisition for the post-Acquisition time period subject to the PSUs. KMG awards granted subsequent to the entry into the definitive agreement for the Acquisition, but prior to the Acquisition Date, were converted to our restricted stock units (“Replacement Awards”), with vesting in three equal installments on the first three anniversaries of the original award date. If the recipient is terminated without cause or resigns with good reason during the 18 months following the Acquisition Date, the Replacement Award will vest as of such termination date in a number of shares equal to 150% of the Replacement Award. The share-based compensation expense of $3,253 related to the Replacement Awards, including accelerated vesting, for the first quarter of fiscal 2019 is included in the table below. The expense for the second quarter of fiscal 2019 and the first and second quarters of fiscal 2020 included in the table below is not material. Share-based compensation expense for the three and six months ended March 31, 2020 and 2019, was as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Cost of sales $ 617 $ 574 $ 1,529 $ 1,629 Research, development and technical 403 442 1,207 1,343 Selling, general and administrative 3,214 2,522 6,261 8,736 Total share-based compensation expense 4,234 3,538 8,997 11,708 Tax benefit (833) (761) (1,771) (2,452) Total share-based compensation expense, net of tax $ 3,401 $ 2,777 $ 7,226 $ 9,256 For additional information regarding the estimation of fair value, refer to Note 16 of "Notes to the Consolidated Financial Statements" included in Item 8 of Part II of our Annual Report on Form 10-K for the fiscal year ended September 30, 2019.

INCOME TAXES

INCOME TAXES	6 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) was enacted by the United States in March 2020. The CARES Act includes provisions to support individuals and businesses in the form of loans, grants, and tax changes, among other types of relief. We are currently assessing the impact of this law, however it did not have a material impact on our provision for income taxes for the three months ended March 31, 2020. We did not and do not intend to take any loans or grants pursuant to the CARES Act or other U.S. Pandemic-related legislation. The Company’s effective income tax rate was 17.8% and 20.1% for the three and six months ended March 31, 2020, respectively, compared to an effective income tax rate of 28.5% and 26.0% for the three and six months ended March 31, 2019, respectively. The decrease in our effective tax rate for the six months ended March 31, 2020 compared to the prior year is primarily attributable to a higher tax benefit related to share based compensation and the favorable impact from the absence of non-deductible KMG acquisition-related costs.

EARNINGS PER SHARE

EARNINGS PER SHARE	6 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Basic earnings per share (EPS) is calculated by dividing Net income available to common stockholders by the weighted-average number of common shares outstanding during the period, excluding the effects of unvested restricted stock awards with a right to receive non-forfeitable dividends, which are considered participating securities as prescribed by the two-class method under ASC 260 “Earnings per Share”. Diluted EPS is calculated in a similar manner, but the weighted-average number of common shares outstanding during the period is increased to include the weighted-average dilutive effect of “in-the-money” stock options and unvested restricted stock shares and units using the treasury stock method. The standards of accounting for earnings per share require companies to provide a reconciliation of the numerator and denominator of the basic and diluted earnings per share computations. Basic and diluted earnings per share were calculated as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Numerator: Net income available to common shares $ 32,899 $ 27,137 $ 71,448 $ 40,580 Denominator: Weighted average common shares 29,287,211 28,997,632 29,182,528 28,065,759 (Denominator for basic calculation) Weighted average effect of dilutive securities 437,968 481,482 483,908 541,274 Diluted weighted average common shares 29,725,179 29,479,114 29,666,436 28,607,033 (Denominator for diluted calculation) Earnings per share: Basic $ 1.12 $ 0.94 $ 2.45 $ 1.45 Diluted $ 1.11 $ 0.92 $ 2.41 $ 1.42 Approximately 111 thousand and 79 thousand shares for the three and six months ended March 31, 2020, respectively, and 216 thousand and 110 thousand for the three and six months ended March 31, 2019, respectively, attributable to outstanding stock options were excluded from the calculation of Diluted earnings per share because the exercise price of the options was greater than the average market price of our common stock and, therefore, their inclusion would have been anti-dilutive.

SEGMENT REPORTING

SEGMENT REPORTING	6 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
SEGMENT REPORTING	SEGMENT REPORTING We identify our segments based on our management structure and the financial information used by our chief executive officer, who is our chief operating decision maker, to assess segment performance and allocate resources among our operating units. We historically had operated predominantly in one industry segment – the development, manufacture and sale of Chemical Mechanical Planarization (CMP) consumables products. In connection with the Acquisition, we reassessed our operating and reportable segments, and determined that we have the following two reportable segments: Electronic Materials Electronic Materials includes products and solutions for the semiconductor industry. We manufacture and sell CMP consumables, including CMP slurries and polishing pads, and high-purity process chemicals used to etch and clean silicon wafers in the production of semiconductors, photovoltaics (solar cells) and flat panel displays. Performance Materials Performance Materials includes pipeline performance products and services, wood treatment products, and products and equipment used in the precision optics industry. Beginning in fiscal 2019 and with the Acquisition, our chief operating decision maker evaluates segment performance based upon revenue and segment adjusted EBITDA. Segment adjusted EBITDA is defined as earnings before interest, income taxes, depreciation and amortization, adjusted for certain items that affect comparability from period to period. These adjustments include items related to the Acquisition, such as expenses incurred to complete the Acquisition, integration-related expenses and the impact of fair value adjustments to inventory acquired from KMG, and certain costs related to the KMG-Bernuth warehouse fire, asset impairment and restructuring charges related to the wood treatment reporting unit. We exclude these items from earnings when presenting our adjusted EBITDA measure because we believe they will be incurred infrequently and/or are otherwise not indicative of a segment's regular, ongoing operating performance. Adjusted EBITDA is also the basis of a performance metric for our fiscal 2020 Short-Term Incentive Program (STIP). In addition, our chief operating decision maker does not use assets by segment to evaluate performance or allocate resources. Therefore, we do not disclose assets by segment. Revenue from external customers by segment are as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Segment Revenue: Electronic Materials: CMP Slurries $ 119,822 $ 110,299 $ 242,148 $ 236,627 Electronic Chemicals 78,497 78,549 156,079 118,371 CMP Pads 20,590 23,998 41,403 48,464 Total Electronic Materials 218,909 212,846 439,630 403,462 Performance Materials 65,284 52,545 127,706 83,707 Total $ 284,193 $ 265,391 $ 567,336 $ 487,169 Capital expenditures by segment are as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Capital Expenditures: Electronic Materials $ 5,094 $ 10,150 $ 13,579 $ 16,549 Performance Materials 29,328 1,363 45,697 1,623 Corporate 3,555 1,018 5,067 2,244 Total $ 37,977 $ 12,531 $ 64,343 $ 20,416 Adjusted EBITDA by segment are as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Segment adjusted EBITDA: Electronic Materials $ 69,603 $ 74,910 $ 150,807 $ 149,735 Performance Materials 29,932 22,660 57,411 35,727 Unallocated corporate expenses (13,604) (12,052) (26,453) (23,094) Interest expense (10,753) (13,331) (22,673) (20,221) Interest income 143 568 458 1,587 Depreciation and amortization (32,550) (27,348) (64,192) (43,889) Acquisition and integration-related expenses (2,285) (2,904) (5,050) (30,198) Charge for fair value write-up of acquired inventory sold — (4,566) — (14,827) Costs related to KMG-Bernuth warehouse fire (See Note 13) and restructuring of wood treatment business (206) — (598) — Costs related to the Pandemic (237) — (237) — Income before income taxes $ 40,043 $ 37,937 $ 89,473 $ 54,820 We began to manage and report our results under the new organizational structure in conjunction with the Acquisition in fiscal 2019 and have reflected this change for all historical periods presented. Since the two segments operate independently and serve different markets and customers, there are no sales between segments. The adjustments to segment EBITDA for the three and six months ended March 31, 2020 represent addbacks of the Acquisition and integration-related expenses, as well as costs related to KMG-Bernuth warehouse fire, restructuring of the wood treatment business, and the Pandemic. The adjustments to segment EBITDA for the three and six months ended March 31, 2019 represent addbacks of Acquisition and integration-related expenses, and a charge for the write-up of inventory acquired from KMG to fair value for inventory sold in the period. The unallocated portions of corporate functions, including finance, legal, human resources, information technology, and corporate development, are not directly attributable to a reportable segment.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS (Policies)	6 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
USE OF ESTIMATES	USE OF ESTIMATES The preparation of financial statements and related disclosures in conformity with U.S. GAAP requires management to make judgments, assumptions and estimates that affect the amounts reported in the consolidated financial statements and accompanying notes. The accounting estimates that require management's most challenging and subjective judgments include, but are not limited to, those estimates related to impairment of long-lived assets, business combinations, asset retirement obligations, goodwill, other intangible assets, income taxes and contingencies. We base our estimates on historical experience, current conditions and on various other assumptions that we believe are reasonable under the circumstances. However, future events are subject to change and estimates and judgments routinely require adjustment. Actual results may differ from these estimates under different assumptions or conditions.
EFFECTS OF RECENT ACCOUNTING PRONOUNCEMENTS	In February 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-02, “Leases” (ASC 842) to change the criteria for recognizing leasing transactions. The provisions of this guidance require a lessee to recognize a right of use asset and a corresponding lease liability for operating leases. Under this guidance, rental expense for operating leases, continues to be recognized on a straight-line basis over the non-cancelable lease term. As of October 1, 2019, the Company began applying the provisions of this standard prospectively for all lease transactions as of and after the effective date. Upon adoption, the Company recorded a lease liability of $30,881 and a right of use asset of $30,115. The difference between the right of use asset and lease liability primarily relates to deferred rent recorded prior to adoption. The new guidance did not have a material impact on our results of operations or cash flows for the three and six months ended March 31, 2020. Refer to Note 11 of this Report on Form 10-Q for additional information regarding the Company’s lease transactions. In February 2018, the FASB issued ASU No. 2018-02 “Income Statement – Reporting Comprehensive Income” (Topic 220). The amendments in this standard allow for an optional one-time reclassification of the stranded tax effects resulting from the change in the U.S. federal corporate income tax rate under the Tax Cuts and Jobs Act (the "Tax Act") from Accumulated other comprehensive income to Retained earnings. The Company adopted this standard effective October 1, 2019, which resulted in an increase of $488 to both Retained earnings and Accumulated other comprehensive loss. In June 2016, the FASB issued ASU No. 2016-13, “Measurement of Credit Losses on Financial Instruments” (Topic 326). The provisions of this standard require financial assets measured at amortized cost to be presented at the net amount expected to be collected. An allowance account would be established to present the net carrying value at the amount expected to be collected. ASU 2016-13 also provides that credit losses relating to available-for-sale debt securities should be recorded through an allowance for credit losses. The guidance was amended through various ASU's subsequent to ASU 2016-13, all of which will be effective for the Company beginning October 1, 2020. We are currently evaluating the impact of implementing this standard on our financial statements. In August 2018, the FASB issued ASU No. 2018-13 “Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement”. The ASU provides specific guidance on various disclosure requirements in Topic 820, including removal, modification and addition to current disclosure requirements. ASU 2018-13 will be effective for us beginning October 1, 2020. We are currently evaluating the impact of implementing this standard on our disclosures. In December 2019, the FASB issued ASU No. 2019-12 “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes”. The ASU was issued to simplify Topic 740 through improving consistency and removing certain exceptions to general principles. ASU 2019-12 will be effective for us beginning October 1, 2021, but early adoption is permitted. We are currently evaluating the impact of implementing this standard on our financial statements. In March 2020, the FASB issued ASU No. 2020-04 "Reference Rate Reform (Topic 848) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” The standard provides optional guidance for accounting for contracts, hedging relationships, and other transactions affected by the reference rate reform, if certain criteria are met. The provisions of this standard are available for election through December 31, 2022. We are currently evaluating the impact of the reference rate reform on our contracts and the resulting impact of adopting this standard on our financial statements.

REVENUE FROM CONTRACTS WITH C_2

REVENUE FROM CONTRACTS WITH CUSTOMERS (Tables)	6 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Reconciliation of contract liability balances	The following table provides information about contract liability balances: March 31, 2020 September 30, 2019 Contract liabilities (current) $ 7,293 $ 5,008 Contract liabilities (noncurrent) 1,580 1,130
Transaction price allocated to remaining performance obligation	The table below discloses (1) the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for contracts with an original duration of greater than one year and (2) when the Company expects to recognize this revenue. Less Than 1 Year 1-3 Years Total Revenue expected to be recognized on contract liability amounts as of March 31, 2020 $ 1,182 $ 1,580 $ 2,762

BUSINESS COMBINATION (Tables)

BUSINESS COMBINATION (Tables)	6 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Summary of components of total consideration	See below for a summary of the different components that comprise the total consideration. Amount Total cash consideration paid for KMG outstanding common stock and equity awards $ 900,756 Cash provided to payoff KMG debt 304,648 Total cash consideration paid 1,205,404 Fair value of Cabot Microelectronics common stock issued for KMG outstanding common stock and equity awards 331,048 Total consideration transferred $ 1,536,452
Summary of preliminary allocation of fair values of assets acquired and liabilities assumed	The following table summarizes the allocation of fair values of assets acquired and liabilities assumed as of the Acquisition Date. Amount Cash $ 23,217 Accounts receivable 63,950 Inventories 68,087 Prepaid expenses and other current assets 14,694 Property, plant and equipment 147,170 Intangible assets 844,800 Other long-term assets 5,805 Accounts payable (28,835) Accrued expenses and other current liabilities (44,216) Deferred income taxes liabilities (156,474) Other long-term liabilities (15,080) Total identifiable net assets acquired 923,118 Goodwill 613,334 Total consideration transferred $ 1,536,452
Components of identifiable intangible asset acquired and their estimated useful lives	The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the Acquisition Date: Fair Value Estimated Useful Life Customer relationships - Flowchem $ 315,000 20 Customer relationships - Electronic chemicals 280,000 19 Customer relationships - all other 109,000 15-16 Technology and know-how 85,500 9-11 Trade name - Flowchem 46,000 Indefinite Trade name - all other 7,000 1-15 EPA product registration rights 2,300 15 Total intangible assets $ 844,800
Summary of pro forma information	The following unaudited supplemental pro forma information summarizes the combined results of operations for Cabot Microelectronics and KMG as if the Acquisition had occurred on October 1, 2017. Three Months Ended Six Months Ended Revenue $ 265,391 $ 549,147 Net income 26,871 64,473 Earnings per share - basic 0.93 2.23 Earnings per share - diluted 0.91 2.19

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	6 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair value of financial instruments	The following table presents financial instruments, other than debt, that we measured at fair value on a recurring basis at March 31, 2020 and September 30, 2019. See Note 10 of this Report on Form 10-Q for a detailed discussion of our debt. We have classified the following assets and liabilities in accordance with the fair value hierarchy set forth in the applicable standards. In instances where the inputs used to measure the fair value of an asset fall into more than one level of the hierarchy, we have classified them based on the lowest-level input that is significant to the determination of the fair value. March 31, 2020 Level 1 Level 2 Level 3 Total Fair Value Assets: Cash and cash equivalents $ 340,702 $ — $ — $ 340,702 Other long-term investments 1,036 — — 1,036 Total assets $ 341,738 $ — $ — $ 341,738 Liabilities: Derivative financial instruments — 41,452 — 41,452 Total liabilities $ — $ 41,452 $ — $ 41,452 September 30, 2019 Level 1 Level 2 Level 3 Total Fair Value Assets: Cash and cash equivalents $ 188,495 $ — $ — $ 188,495 Other long-term investments 980 — — 980 Total assets $ 189,475 $ — $ — $ 189,475 Liabilities: Derivative financial instruments — 24,244 — 24,244 Total liabilities $ — $ 24,244 $ — $ 24,244

INVENTORIES (Tables)

INVENTORIES (Tables)	6 Months Ended
	Mar. 31, 2020
Inventory Disclosure [Abstract]
Schedule of inventories	Inventories consisted of the following: March 31, 2020 September 30, 2019 Raw materials $ 63,296 $ 60,157 Work in process 17,915 12,940 Finished goods 76,661 72,181 Total $ 157,872 $ 145,278

GOODWILL AND OTHER INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	6 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill activity	Goodwill activity for each of the Company’s reportable segments, which carry goodwill, Electronic Materials and Performance Materials, for the six months ended March 31, 2020. Electronic Materials Performance Materials Total Balance at September 30, 2019 $ 352,797 $ 357,274 $ 710,071 Foreign currency translation impact 465 (1,918) (1,453) Other — 1,205 1,205 Balance at March 31, 2020 $ 353,262 $ 356,561 $ 709,823
Schedule of other intangible assets	The components of other intangible assets are: March 31, 2020 September 30, 2019 Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Other intangible assets subject to amortization: Product technology, trade secrets and know-how $ 121,579 $ 42,230 $ 123,948 $ 37,993 Acquired patents and licenses 9,023 8,558 9,023 8,397 Customer relationships, trade names, and distribution rights 685,061 103,386 684,764 64,471 Total other intangible assets subject to amortization 815,663 154,174 817,735 110,861 Other intangible assets not subject to amortization: Other indefinite-lived intangibles* 47,170 47,170 Total other intangible assets not subject to amortization 47,170 47,170 Total other intangible assets $ 862,833 $ 154,174 $ 864,905 $ 110,861 *Other indefinite-lived intangible assets not subject to amortization consist primarily of trade names.
Schedule of amortization expense on intangible assets	Estimated future amortization expense for the five succeeding fiscal years is as follows: Fiscal Year Estimated Remainder of 2020 $ 42,429 2021 90,474 2022 80,974 2023 68,480 2024 60,528

OTHER LONG-TERM ASSETS (Tables)

OTHER LONG-TERM ASSETS (Tables)	6 Months Ended
	Mar. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other long-term assets	Other long-term assets consisted of the following: March 31, 2020 September 30, 2019 Long-term right of use asset $ 29,715 $ — Long-term contract assets 3,776 1,164 Long-term SERP investment 1,036 980 Prepaid unamortized debt issuance cost - revolver 623 709 Other long-term assets 2,574 2,858 Total $ 37,724 $ 5,711

ACCRUED EXPENSES, INCOME TAXE_2

ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES (Tables)	6 Months Ended
	Mar. 31, 2020
Payables and Accruals [Abstract]
Accrued expenses, income taxes payable and other current liabilities	Accrued expenses, income taxes payable and other current liabilities consisted of the following: March 31, 2020 September 30, 2019 Accrued compensation $ 33,833 $ 33,809 Income taxes payable 16,470 15,725 Dividends payable 13,510 12,953 Interest rate swap liability 12,410 5,351 Contract liabilities (current) 7,293 5,008 Current portion of operating lease liability 5,498 — Taxes, other than income taxes 5,330 6,281 Goods and services received, not yet invoiced 3,950 3,075 KMG - Bernuth warehouse fire-related (See Note 13) — 7,998 Accrued interest — 3,739 Other 11,095 9,679 Total $ 109,389 $ 103,618

DEBT (Tables)

DEBT (Tables)	6 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Schedule of principal repayments of debt	As of March 31, 2020, scheduled principal repayments of the Term Loan were: Fiscal Year Principal Repayments Remainder of 2020 $ 5,325 2021 10,650 2022 10,650 2023 10,650 2024 10,650 Greater than 5 years 893,762 Total $ 941,687

LEASES (Tables)

LEASES (Tables)	6 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Future maturities of operating lease liabilities	Future maturities of operating lease liabilities for the years ended September 30 are as follows: Fiscal Year Amount Remainder of 2020 $ 3,356 2021 5,538 2022 5,185 2023 4,728 2024 4,068 2025 and future years 11,544 Total future lease payments 34,419 Less: Imputed interest 3,531 Operating lease liability 30,888 Less: Current portion of operating lease liability 5,498 Long-term portion of operating lease liability $ 25,390
Minimum lease payments under operating leases	As of September 30, 2019, minimum lease payments under operating leases with noncancelable terms in excess of one are as follows: Fiscal Year Amount 2020 $ 6,984 2021 4,941 2022 4,291 2023 4,122 2024 3,710 Thereafter 12,010 Total future minimum lease payments $ 36,058

DERIVATIVE FINANCIAL INSTRUME_2

DERIVATIVE FINANCIAL INSTRUMENTS (Tables)	6 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivative instruments in the Consolidated Balance Sheets	The fair value of our derivative instruments included in the Consolidated Balance Sheets, which was determined using level 2 inputs, was as follows: Derivative Assets Derivative Liabilities Consolidated Balance Sheet Location March 31, 2020 September 30, 2019 March 31, 2020 September 30, 2019 Derivatives designated as hedging instruments Interest rate swap contract Accrued expenses, income taxes payable and other current liabilities $ — $ — $ 12,410 $ 5,351 Other long-term liabilities $ — $ — $ 28,585 $ 18,841 Derivatives not designated as hedging instruments Foreign exchange contracts Accrued expenses, income taxes payable and other current liabilities $ — $ — $ 458 $ 52
Schedule of derivative instruments on Consolidated Statements of Income	The following table summarizes the effect of our derivative instruments on our Consolidated Statements of Income for the three and six months ended March 31, 2020 and 2019: Gain (Loss) Recognized in Statement of Income Three Months Ended March 31, Six Months Ended March 31, Statement of Income Location 2020 2019 2020 2019 Derivatives not designated as hedging instruments Foreign exchange contracts Other income (expense), net $ (268) $ (348) $ (262) $ (38)

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	6 Months Ended
	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other comprehensive income (loss)	The table below summarizes the components of Accumulated other comprehensive income (loss) (AOCI), net of Provision for income taxes/(benefit), for the three and six months ended March 31, 2020 and 2019: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Beginning Balance $ (3,616) $ 6,713 $ (23,238) $ 4,539 Foreign currency translation adjustment (19,752) (1,621) (3,935) 1,412 Income taxes 27 629 61 21 Foreign currency translation adjustment, net of tax (19,725) (992) (3,874) 1,433 Change in pension and other postretirement — 251 — — Unrealized gain loss on cash flow hedges: Change in fair value (23,655) (8,352) (19,340) (8,352) Reclassification adjustment into earnings 1,366 (1) 2,537 (1) Income taxes 4,982 1,879 3,755 1,879 Unrealized loss on cash flow hedges, net of tax (17,307) (6,474) (13,048) (6,474) Effect of the adoption of the stranded tax effect accounting standards — — (497) — Income taxes — — 9 — Effect of the adoption of the stranded tax effect accounting standards, net of tax — — (488) — Net Change (37,032) (7,215) (17,410) (5,041) Ending Balance $ (40,648) $ (502) $ (40,648) $ (502)

SHARE-BASED COMPENSATION PLANS

SHARE-BASED COMPENSATION PLANS (Tables)	6 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Schedule of share-based compensation expense	Share-based compensation expense for the three and six months ended March 31, 2020 and 2019, was as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Cost of sales $ 617 $ 574 $ 1,529 $ 1,629 Research, development and technical 403 442 1,207 1,343 Selling, general and administrative 3,214 2,522 6,261 8,736 Total share-based compensation expense 4,234 3,538 8,997 11,708 Tax benefit (833) (761) (1,771) (2,452) Total share-based compensation expense, net of tax $ 3,401 $ 2,777 $ 7,226 $ 9,256

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	6 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Schedule of earnings per share	The standards of accounting for earnings per share require companies to provide a reconciliation of the numerator and denominator of the basic and diluted earnings per share computations. Basic and diluted earnings per share were calculated as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Numerator: Net income available to common shares $ 32,899 $ 27,137 $ 71,448 $ 40,580 Denominator: Weighted average common shares 29,287,211 28,997,632 29,182,528 28,065,759 (Denominator for basic calculation) Weighted average effect of dilutive securities 437,968 481,482 483,908 541,274 Diluted weighted average common shares 29,725,179 29,479,114 29,666,436 28,607,033 (Denominator for diluted calculation) Earnings per share: Basic $ 1.12 $ 0.94 $ 2.45 $ 1.45 Diluted $ 1.11 $ 0.92 $ 2.41 $ 1.42

SEGMENT REPORTING (Tables)

SEGMENT REPORTING (Tables)	6 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Schedule of segment revenue	Revenue from external customers by segment are as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Segment Revenue: Electronic Materials: CMP Slurries $ 119,822 $ 110,299 $ 242,148 $ 236,627 Electronic Chemicals 78,497 78,549 156,079 118,371 CMP Pads 20,590 23,998 41,403 48,464 Total Electronic Materials 218,909 212,846 439,630 403,462 Performance Materials 65,284 52,545 127,706 83,707 Total $ 284,193 $ 265,391 $ 567,336 $ 487,169
Schedule of capital expenditures by segment	Capital expenditures by segment are as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Capital Expenditures: Electronic Materials $ 5,094 $ 10,150 $ 13,579 $ 16,549 Performance Materials 29,328 1,363 45,697 1,623 Corporate 3,555 1,018 5,067 2,244 Total $ 37,977 $ 12,531 $ 64,343 $ 20,416
Schedule of segment adjusted EBITDA	Adjusted EBITDA by segment are as follows: Three Months Ended March 31, Six Months Ended March 31, 2020 2019 2020 2019 Segment adjusted EBITDA: Electronic Materials $ 69,603 $ 74,910 $ 150,807 $ 149,735 Performance Materials 29,932 22,660 57,411 35,727 Unallocated corporate expenses (13,604) (12,052) (26,453) (23,094) Interest expense (10,753) (13,331) (22,673) (20,221) Interest income 143 568 458 1,587 Depreciation and amortization (32,550) (27,348) (64,192) (43,889) Acquisition and integration-related expenses (2,285) (2,904) (5,050) (30,198) Charge for fair value write-up of acquired inventory sold — (4,566) — (14,827) Costs related to KMG-Bernuth warehouse fire (See Note 13) and restructuring of wood treatment business (206) — (598) — Costs related to the Pandemic (237) — (237) — Income before income taxes $ 40,043 $ 37,937 $ 89,473 $ 54,820

BACKGROUND AND BASIS OF PRESE_2

BACKGROUND AND BASIS OF PRESENTATION (Details)	3 Months Ended
	Mar. 31, 2020segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments	2

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2019	Mar. 31, 2020	Oct. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability		$ 30,888
Operating lease, right of use asset		$ 29,715
Effect of the adoption of the stranded tax effect accounting standards	$ 0
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect of the adoption of the stranded tax effect accounting standards	$ 488
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability			$ 30,881
Operating lease, right of use asset			$ 30,115

REVENUE FROM CONTRACTS WITH C_3

REVENUE FROM CONTRACTS WITH CUSTOMERS - Reconciliation of Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2020	Sep. 30, 2019
Contract with Customer, Liability [Abstract]
Contract liabilities (current)	$ 7,293	$ 7,293	$ 5,008
Contract liabilities (noncurrent)	1,580	1,580	$ 1,130
Change in Contract with Customer, Liability [Abstract]
Revenue recognized in contract liability	$ 769	$ 3,027

REVENUE FROM CONTRACTS WITH C_4

REVENUE FROM CONTRACTS WITH CUSTOMERS - Transaction Price Allocated to Remaining Performance Obligations (Details) $ in Thousands	Mar. 31, 2020USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized on contract liability amounts as of end of period	$ 2,762
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized on contract liability amounts as of end of period	$ 1,182
Revenue, Performance Obligation [Abstract]
Revenue expected to be recognized on contract liability, satisfaction period	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized on contract liability amounts as of end of period	$ 1,580
Revenue, Performance Obligation [Abstract]
Revenue expected to be recognized on contract liability, satisfaction period	2 years

BUSINESS COMBINATION - Narrativ

BUSINESS COMBINATION - Narrative (Details) - USD ($)	Nov. 15, 2018	Mar. 31, 2020	Sep. 30, 2019	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Business Acquisition [Line Items]
Acquisition of business, net of cash acquired					$ 0	$ 1,182,186,000
Asset impairment			$ 67,372,000
Goodwill		$ 709,823,000	710,071,000		709,823,000
Share-based compensation expense					8,997,000	11,708,000
Non-cash charge on inventory step up of acquired inventory sold		0		$ 4,566,000	0	14,827,000
Revolving credit facility | Credit Agreement | JPMorgan Chase Bank, N.A.
Business Acquisition [Line Items]
Debt, term	7 years
Electronic Materials
Business Acquisition [Line Items]
Goodwill		353,262,000	352,797,000		353,262,000
Performance Materials
Business Acquisition [Line Items]
Goodwill		356,561,000	$ 357,274,000		356,561,000
Term loan facility | Revolving credit facility | Credit Agreement
Business Acquisition [Line Items]
Debt, term	7 years
Term loan facility | Revolving credit facility | Credit Agreement | JPMorgan Chase Bank, N.A.
Business Acquisition [Line Items]
Debt, term	7 years
Debt, face amount	$ 1,065,000,000
KMG
Business Acquisition [Line Items]
Business acquisition, percentage of voting interest acquired	100.00%
Acquisition of business, net of cash acquired	$ 1,513,235,000
Consideration transferred	1,536,452,000
Cash acquired from acquisition	$ 23,217,000
Amount received for each share of KMG common stock (in dollars per share)	$ 55.65
Share percentage received for each share of KMG common stock (in shares)	0.2000
Shares issued to acquire entity (in shares)	3,237,005
Share price of shares issued to acquire entity (in dollars per share)	$ 102.27
Weighted average useful life	17 years 10 months 24 days
Goodwill	$ 613,334,000
Transaction costs		117,000			323,000
Net sales		137,996,000			271,429,000
Net income		16,604,000			31,290,000
KMG | Acquisition-related costs
Business Acquisition [Line Items]
Transaction costs				621,000		1,436,000
Share-based compensation expense				$ 51,000		$ 154,000
KMG | Selling, general and administrative
Business Acquisition [Line Items]
Transaction costs		$ 2,285,000			$ 5,050,000
KMG | Electronic Materials
Business Acquisition [Line Items]
Goodwill	259,859,000
KMG | Performance Materials
Business Acquisition [Line Items]
Goodwill	$ 353,475,000

BUSINESS COMBINATION - Consider

BUSINESS COMBINATION - Consideration (Details) - KMG $ in Thousands	Nov. 15, 2018USD ($)
Business Combination, Consideration Transferred [Abstract]
Total cash consideration paid for KMG outstanding common stock and equity awards	$ 900,756
Cash provided to payoff KMG debt	304,648
Total cash consideration paid	1,205,404
Fair value of Cabot Microelectronics common stock issued for KMG outstanding common stock and equity awards	331,048
Total consideration transferred	$ 1,536,452

BUSINESS COMBINATION - Allocati

BUSINESS COMBINATION - Allocation of Fair Values of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019	Nov. 15, 2018
Fair values of assets acquired and liabilities assumed [Abstract]
Goodwill	$ 709,823	$ 710,071
KMG
Fair values of assets acquired and liabilities assumed [Abstract]
Cash			$ 23,217
Accounts receivable			63,950
Inventories			68,087
Prepaid expenses and other current assets			14,694
Property, plant and equipment			147,170
Intangible assets			844,800
Other long-term assets			5,805
Accounts payable			(28,835)
Accrued expenses and other current liabilities			(44,216)
Deferred income taxes liabilities			(156,474)
Other long-term liabilities			(15,080)
Total identifiable net assets acquired			923,118
Goodwill			613,334
Total consideration transferred			$ 1,536,452

BUSINESS COMBINATION - Identifi

BUSINESS COMBINATION - Identifiable Intangible Assets Acquired (Details) - KMG $ in Thousands	Nov. 15, 2018USD ($)
Fair Value
Intangible assets	$ 844,800
Trade name - Flowchem
Acquired Indefinite-lived Intangible Assets [Line Items]
Fair value, indefinite lived intangible assets	46,000
Customer relationships - Flowchem
Fair Value
Fair value, finite lived intangible assets	$ 315,000
Estimated useful live, finite lived intangible asset	20 years
Customer relationships - Electronic chemicals
Fair Value
Fair value, finite lived intangible assets	$ 280,000
Estimated useful live, finite lived intangible asset	19 years
Customer relationships - all other
Fair Value
Fair value, finite lived intangible assets	$ 109,000
Customer relationships - all other | Minimum
Fair Value
Estimated useful live, finite lived intangible asset	15 years
Customer relationships - all other | Maximum
Fair Value
Estimated useful live, finite lived intangible asset	16 years
Technology and know-how
Fair Value
Fair value, finite lived intangible assets	$ 85,500
Technology and know-how | Minimum
Fair Value
Estimated useful live, finite lived intangible asset	9 years
Technology and know-how | Maximum
Fair Value
Estimated useful live, finite lived intangible asset	11 years
Trade name - all other
Fair Value
Fair value, finite lived intangible assets	$ 7,000
Trade name - all other | Minimum
Fair Value
Estimated useful live, finite lived intangible asset	1 year
Trade name - all other | Maximum
Fair Value
Estimated useful live, finite lived intangible asset	15 years
EPA product registration rights
Fair Value
Fair value, finite lived intangible assets	$ 2,300
Estimated useful live, finite lived intangible asset	15 years

BUSINESS COMBINATION - Pro Form

BUSINESS COMBINATION - Pro Forma Information (Details) - KMG - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2019	Mar. 31, 2019
Business Acquisition, Pro Forma Information [Abstract]
Revenue	$ 265,391	$ 549,147
Net income	$ 26,871	$ 64,473
Earnings per share - basic (in dollars per share)	$ 0.93	$ 2.23
Earnings per share - diluted (in dollars per share)	$ 0.91	$ 2.19

FAIR VALUE OF FINANCIAL INSTR_3

FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - Recurring - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Assets:
Cash and cash equivalents	$ 340,702	$ 188,495
Other long-term investments	1,036	980
Total assets	341,738	189,475
Liabilities:
Derivative financial instruments	41,452	24,244
Total liabilities	41,452	24,244
Level 1
Assets:
Cash and cash equivalents	340,702	188,495
Other long-term investments	1,036	980
Total assets	341,738	189,475
Liabilities:
Derivative financial instruments	0	0
Total liabilities	0	0
Level 2
Assets:
Cash and cash equivalents	0	0
Other long-term investments	0	0
Total assets	0	0
Liabilities:
Derivative financial instruments	41,452	24,244
Total liabilities	41,452	24,244
Level 3
Assets:
Cash and cash equivalents	0	0
Other long-term investments	0	0
Total assets	0	0
Liabilities:
Derivative financial instruments	0	0
Total liabilities	$ 0	$ 0

INVENTORIES (Details)

INVENTORIES (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Inventory, Net, Items Net of Reserve Alternative [Abstract]
Raw materials	$ 63,296	$ 60,157
Work in process	17,915	12,940
Finished goods	76,661	72,181
Total	$ 157,872	$ 145,278

GOODWILL AND OTHER INTANGIBLE_3

GOODWILL AND OTHER INTANGIBLE ASSETS - Goodwill Rollforward (Details) $ in Thousands	6 Months Ended
	Mar. 31, 2020USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 710,071
Foreign currency translation impact	(1,453)
Other	1,205
Goodwill, ending balance	709,823
Electronic Materials
Goodwill [Roll Forward]
Goodwill, beginning balance	352,797
Foreign currency translation impact	465
Other	0
Goodwill, ending balance	353,262
Performance Materials
Goodwill [Roll Forward]
Goodwill, beginning balance	357,274
Foreign currency translation impact	(1,918)
Other	1,205
Goodwill, ending balance	$ 356,561

GOODWILL AND OTHER INTANGIBLE_4

GOODWILL AND OTHER INTANGIBLE ASSETS - Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, gross carrying amount	$ 815,663	$ 817,735
Other intangible assets subject to amortization, accumulated amortization	154,174	110,861
Other intangible assets not subject to amortization:
Other intangible assets not subject to amortization	47,170	47,170
Other intangible assets	862,833	864,905
Other indefinite-lived intangibles
Other intangible assets not subject to amortization:
Other intangible assets not subject to amortization	47,170	47,170
Product technology, trade secrets and know-how
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, gross carrying amount	121,579	123,948
Other intangible assets subject to amortization, accumulated amortization	42,230	37,993
Acquired patents and licenses
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, gross carrying amount	9,023	9,023
Other intangible assets subject to amortization, accumulated amortization	8,558	8,397
Customer relationships, trade names, and distribution rights
Other intangible assets subject to amortization:
Other intangible assets subject to amortization, gross carrying amount	685,061	684,764
Other intangible assets subject to amortization, accumulated amortization	$ 103,386	$ 64,471

GOODWILL AND OTHER INTANGIBLE_5

GOODWILL AND OTHER INTANGIBLE ASSETS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 22,014	$ 16,960	$ 43,378	$ 26,318

GOODWILL AND OTHER INTANGIBLE_6

GOODWILL AND OTHER INTANGIBLE ASSETS - Amortization Expense (Details) $ in Thousands	Mar. 31, 2020USD ($)
Estimated Amortization Expense
Remainder of 2020	$ 42,429
2021	90,474
2022	80,974
2023	68,480
2024	$ 60,528

OTHER LONG-TERM ASSETS (Details

OTHER LONG-TERM ASSETS (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Other long-term assets [Abstract]
Long-term right of use asset	$ 29,715
Long-term contract assets	3,776	$ 1,164
Long-term SERP investment	1,036	980
Prepaid unamortized debt issuance cost - revolver	623	709
Other long-term assets	2,574	2,858
Total	$ 37,724	$ 5,711

ACCRUED EXPENSES, INCOME TAXE_3

ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Payables and Accruals [Abstract]
Accrued compensation	$ 33,833	$ 33,809
Income taxes payable	16,470	15,725
Dividends payable	13,510	12,953
Interest rate swap liability	12,410	5,351
Contract liabilities (current)	7,293	5,008
Current portion of operating lease liability	5,498
Taxes, other than income taxes	5,330	6,281
Goods and services received, not yet invoiced	3,950	3,075
KMG - Bernuth warehouse fire-related (See Note 13)	0	7,998
Accrued interest	0	3,739
Other	11,095	9,679
Total	$ 109,389	$ 103,618

DEBT - Narrative (Details)

DEBT - Narrative (Details)	Mar. 13, 2020USD ($)	Nov. 15, 2018USD ($)	Mar. 31, 2020USD ($)	Mar. 31, 2019USD ($)	Sep. 30, 2019USD ($)
Long-term Debt, Unclassified [Abstract]
Current portion of long-term debt			$ 10,650,000		$ 13,313,000
Prepaid debt issuance cost			16,420,000		17,900,000
Proceeds from revolving line of credit			150,000,000	$ 0
Revolving credit facility, outstanding			$ 150,000,000		$ 0
Percentage of debt hedged by interest rate swaps				70.00%
Credit Agreement | Minimum
Long-term Debt, Unclassified [Abstract]
Secured net leverage ratio			1
Credit Agreement | Maximum
Long-term Debt, Unclassified [Abstract]
Secured net leverage ratio			2.02
Credit Agreement | Revolving credit facility | Term loan facility
Long-term Debt, Unclassified [Abstract]
Debt, term		7 years
Percentage of initial principal payment amount		0.25%
Current portion of long-term debt			$ 10,650,000
Prepaid debt issuance cost			16,420,000
Credit Agreement | Revolving credit facility | Term loan facility | Level 2
Long-term Debt, Unclassified [Abstract]
Fair value of debt			941,687,000
Credit Agreement | Revolving credit facility | Term loan facility | LIBOR Floor
Long-term Debt, Unclassified [Abstract]
Basis spread on variable rate		0.00%
Credit Agreement | Revolving credit facility | Term loan facility | LIBOR
Long-term Debt, Unclassified [Abstract]
Basis spread on variable rate		2.00%
Credit Agreement | Revolving credit facility | Term loan facility | Base rate
Long-term Debt, Unclassified [Abstract]
Basis spread on variable rate		1.00%
Credit Agreement | Revolving credit facility | Line of credit
Long-term Debt, Unclassified [Abstract]
Debt, term		5 years
Debt requirements, annual excess cash flow		50.00%
Debt requirements, net cash proceeds of recovery events and non-ordinary course asset sales		100.00%
Proceeds from revolving line of credit	$ 150,000,000
Revolving credit facility, outstanding			150,000,000
Available credit under the Revolving Credit Facility			$ 50,000,000
Credit Agreement | Revolving credit facility | Line of credit | LIBOR
Long-term Debt, Unclassified [Abstract]
Basis spread on variable rate		1.50%
Credit Agreement | Revolving credit facility | Line of credit | Base rate
Long-term Debt, Unclassified [Abstract]
Basis spread on variable rate		0.50%
Commitment fee percentage		0.25%
Credit Agreement | JPMorgan Chase Bank, N.A. | Revolving credit facility
Long-term Debt, Unclassified [Abstract]
Debt, term		7 years
Line of credit facility, borrowing capacity		$ 1,265,000,000
Credit Agreement | JPMorgan Chase Bank, N.A. | Revolving credit facility | Minimum
Long-term Debt, Unclassified [Abstract]
Secured net leverage ratio			1
Credit Agreement | JPMorgan Chase Bank, N.A. | Revolving credit facility | Maximum
Long-term Debt, Unclassified [Abstract]
Secured net leverage ratio			4
Credit Agreement | JPMorgan Chase Bank, N.A. | Revolving credit facility | Term loan facility
Long-term Debt, Unclassified [Abstract]
Debt, term		7 years
Debt, face amount		$ 1,065,000,000
Credit Agreement | JPMorgan Chase Bank, N.A. | Revolving credit facility | Line of credit
Long-term Debt, Unclassified [Abstract]
Line of credit facility, borrowing capacity		200,000,000
Credit Agreement | JPMorgan Chase Bank, N.A. | Letter of credit sub-facility | Line of credit
Long-term Debt, Unclassified [Abstract]
Line of credit facility, borrowing capacity		$ 50,000,000

DEBT - Principal Repayments (De

DEBT - Principal Repayments (Details) - Term loan facility $ in Thousands	Mar. 31, 2020USD ($)
Principal Repayments
Remainder of 2020	$ 5,325
2021	10,650
2022	10,650
2023	10,650
2024	10,650
Greater than 5 years	893,762
Total	$ 941,687

LEASES - Narrative (Details)

LEASES - Narrative (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2020USD ($)	Mar. 31, 2020USD ($)
Leases [Abstract]
Weighted average lease term for operating leases	7 years	7 years
Lease cost	$ 2,320	$ 4,806
Operating lease cost	1,903	3,886
Short-term and variable lease costs	417	920
Operating lease, right of use asset	29,715	29,715
Current portion of lease liability for operating leases	5,498	5,498
Long-term portion of lease liability for operating leases	$ 25,390	$ 25,390
Weighted average discount rate for operating leases	3.02%	3.02%

LEASES - Maturities of Operatin

LEASES - Maturities of Operating Lease Liabilities (Details) $ in Thousands	Mar. 31, 2020USD ($)
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
Remainder of 2020	$ 3,356
2021	5,538
2022	5,185
2023	4,728
2024	4,068
2025 and future years	11,544
Total future lease payments	34,419
Less: Imputed interest	3,531
Operating lease liability	30,888
Less: Current portion of operating lease liability	5,498
Long-term portion of operating lease liability	$ 25,390

LEASES - Minimum Lease Payments

LEASES - Minimum Lease Payments Under Operating Leases (Details) $ in Thousands	Sep. 30, 2019USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2020	$ 6,984
2021	4,941
2022	4,291
2023	4,122
2024	3,710
Thereafter	12,010
Total future minimum lease payments	$ 36,058

DERIVATIVE FINANCIAL INSTRUME_3

DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2020	Sep. 30, 2019
Derivative Instruments [Abstract]
Gain (loss) reclassified from accumulated other comprehensive income into interest expense, estimated time to transfer	12 months
Interest rate swap
Derivative Instruments [Abstract]
Derivative notional amount	$ 652,000	$ 652,000
Unrealized gain (loss) on cash flow hedging instruments	(18,367)	(15,017)
Reclassified from accumulated other comprehensive income into interest expense	12,410
Foreign contracts | Buy
Derivative Instruments [Abstract]
Derivative notional amount	5,746	5,746	$ 6,239
Foreign contracts | Sell
Derivative Instruments [Abstract]
Derivative notional amount	$ 24,800	$ 24,800	$ 24,270

DERIVATIVE FINANCIAL INSTRUME_4

DERIVATIVE FINANCIAL INSTRUMENTS - Fair Value of Derivative Instruments in the Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Derivatives designated as hedging instruments | Interest rate swap | Accrued expenses, income taxes payable and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative assets	$ 0	$ 0
Derivative liabilities	12,410	5,351
Derivatives designated as hedging instruments | Interest rate swap | Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative assets	0	0
Derivative liabilities	28,585	18,841
Derivatives not designated as hedging instruments | Foreign contracts | Accrued expenses, income taxes payable and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative assets	0	0
Derivative liabilities	$ 458	$ 52

DERIVATIVE FINANCIAL INSTRUME_5

DERIVATIVE FINANCIAL INSTRUMENTS - Effect of Derivative Instruments on the Consolidated Statement of Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Derivatives not designated as hedging instruments | Foreign contracts | Other income (expense), net
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Other income (loss), net	$ (268)	$ (348)	$ (262)	$ (38)

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	1 Months Ended	6 Months Ended	12 Months Ended
	Sep. 30, 2016USD ($)party	Mar. 31, 2020USD ($)	Sep. 30, 2019USD ($)
Postretirement Obligations in Foreign Jurisdictions [Abstract]
Expected future benefit payments		$ 7,872
Abrasive particle supply agreement
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		27,497
Non-water-based carrier fluid
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		10,216
Abrasive particles
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation		3,638
KMG-Bernuth
Environmental Exit Cost [Line Items]
Remediation expense recognized		593	$ 9,494
Estimated remediation cost	$ 22,000
Number of other parties in agreement | party	7
Estimated reserve, remaining		$ 553

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ 1,029,999	$ 980,377	$ 1,008,167	$ 980,377	$ 666,692
Other comprehensive income, net of tax	(37,032)		(7,215)	(16,922)	(5,041)
Other comprehensive income, net of tax, including stranded tax effect				(17,410)
Balance at end of period	1,009,410	1,029,999	1,025,867	1,009,410	1,025,867
Effect of the adoption of the stranded tax effect accounting standards		0
Accounting Standards Update 2018-02 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income, before tax	0		0	(497)	0
Reclassification from AOCI, tax	0		0	9	0
Reclassification from AOCI, net of tax	0		0	(488)	0
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(3,616)	(23,238)	6,713	(23,238)	4,539
Balance at end of period	(40,648)	(3,616)	(502)	(40,648)	(502)
Effect of the adoption of the stranded tax effect accounting standards		$ (488)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income, before tax	(19,752)		(1,621)	(3,935)	1,412
Reclassification from AOCI, tax	27		629	61	21
Reclassification from AOCI, net of tax	(19,725)		(992)	(3,874)	1,433
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassification from AOCI, net of tax	0		251	0	0
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income, before tax	1,366		(1)	2,537	(1)
Reclassification from AOCI, tax	4,982		1,879	3,755	1,879
Reclassification from AOCI, net of tax	(17,307)		(6,474)	(13,048)	(6,474)
Change in fair value	$ (23,655)		$ (8,352)	$ (19,340)	$ (8,352)

SHARE-BASED COMPENSATION PLAN_2

SHARE-BASED COMPENSATION PLANS - Narrative (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Dec. 31, 2018USD ($)	Mar. 31, 2020USD ($)installment	Mar. 31, 2019USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 8,997	$ 11,708
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of vesting installments | installment		3
Period of Termination to Accelerate Vest Awards to Shares		18 months
Percentage of Accelerate Vest Awards to Number of Shares		150.00%
Stock Option and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 3,253

SHARE-BASED COMPENSATION PLAN_3

SHARE-BASED COMPENSATION PLANS - Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 4,234	$ 3,538	$ 8,997	$ 11,708
Tax benefit	(833)	(761)	(1,771)	(2,452)
Total share-based compensation expense, net of tax	3,401	2,777	7,226	9,256
Cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	617	574	1,529	1,629
Research, development and technical
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	403	442	1,207	1,343
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 3,214	$ 2,522	$ 6,261	$ 8,736

INCOME TAXES (Details)

INCOME TAXES (Details)	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Effective tax rate	17.80%	28.50%	20.10%	26.00%

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income available to common shares	$ 32,899	$ 27,137	$ 71,448	$ 40,580
Denominator:
Weighted average common shares (Denominator for basis calculation) (in shares)	29,287,211	28,997,632	29,182,528	28,065,759
Weighted average effect of dilutive securities
Weighted average effect of dilutive securities (in shares)	437,968	481,482	483,908	541,274
Diluted weighted average common shares (Denominator for diluted calculation) (in shares)	29,725,179	29,479,114	29,666,436	28,607,033
Earnings per share:
Basic (in dollars per share)	$ 1.12	$ 0.94	$ 2.45	$ 1.45
Diluted (in dollars per share)	$ 1.11	$ 0.92	$ 2.41	$ 1.42
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding stock options excluded from calculation of diluted earnings per share (in shares)	111,000	216,000	79,000	110,000

SEGMENT REPORTING - Narrative (

SEGMENT REPORTING - Narrative (Details) - segment	Nov. 14, 2018	Mar. 31, 2020
Segment Reporting [Abstract]
Number of operating segments	1
Number of reportable segments		2

SEGMENT REPORTING - Revenue fro

SEGMENT REPORTING - Revenue from External Customers (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Revenue	$ 284,193	$ 265,391	$ 567,336	$ 487,169
Electronic Materials
Segment Reporting Information [Line Items]
Revenue	218,909	212,846	439,630	403,462
CMP Slurries
Segment Reporting Information [Line Items]
Revenue	119,822	110,299	242,148	236,627
Electronic Chemicals
Segment Reporting Information [Line Items]
Revenue	78,497	78,549	156,079	118,371
CMP Pads
Segment Reporting Information [Line Items]
Revenue	20,590	23,998	41,403	48,464
Performance Materials
Segment Reporting Information [Line Items]
Revenue	$ 65,284	$ 52,545	$ 127,706	$ 83,707

SEGMENT REPORTING - Capital Exp

SEGMENT REPORTING - Capital Expenditures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Capital expenditures	$ 37,977	$ 12,531	$ 64,343	$ 20,416
Operating segment | Electronic Materials
Segment Reporting Information [Line Items]
Capital expenditures	5,094	10,150	13,579	16,549
Operating segment | Performance Materials
Segment Reporting Information [Line Items]
Capital expenditures	29,328	1,363	45,697	1,623
Unallocated corporate expenses
Segment Reporting Information [Line Items]
Capital expenditures	$ 3,555	$ 1,018	$ 5,067	$ 2,244

SEGMENT REPORTING - Reconciliat

SEGMENT REPORTING - Reconciliation from Segment Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Interest expense	$ (10,753)	$ (13,331)	$ (22,673)	$ (20,221)
Interest income	143	568	458	1,587
Depreciation and amortization	(32,550)	(27,348)	(64,192)	(43,889)
Acquisition and integration-related expenses	(2,285)	(2,904)	(5,050)	(30,198)
Charge for fair value write-up of acquired inventory sold	0	(4,566)	0	(14,827)
Costs related to KMG-Bernuth warehouse fire (See Note 13) and restructuring of wood treatment business	(206)	0	(598)	0
Costs related to the Pandemic	(237)	0	(237)	0
Income before income taxes	40,043	37,937	89,473	54,820
Operating segment | Electronic Materials
Segment Reporting Information [Line Items]
Adjusted EBITDA	69,603	74,910	150,807	149,735
Operating segment | Performance Materials
Segment Reporting Information [Line Items]
Adjusted EBITDA	29,932	22,660	57,411	35,727
Unallocated corporate expenses
Segment Reporting Information [Line Items]
Unallocated corporate expenses	$ (13,604)	$ (12,052)	$ (26,453)	$ (23,094)

Uncategorized Items - ccmp-2020

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (933,000)
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (933,000)