Ashland (ASH) 10-Q 4 Feb 21 2021 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information	3 Months Ended
	Dec. 31, 2020shares
Cover [Abstract]
Entity Registrant Name	ASHLAND GLOBAL HOLDINGS INC.
Entity Central Index Key	0001674862
Current Fiscal Year End Date	--09-30
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity File Number	333-211719
Entity Tax Identification Number	81-2587835
Entity Address, Address Line One	8145 Blazer Drive
Entity Address, City or Town	Wilmington
Entity Address, State or Province	DE
Entity Address, Postal Zip Code	19808
Entity Shell Company	false
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false
City Area Code	302
Local Phone Number	995-3000
Entity Common Stock, Shares Outstanding	60,667,388
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Trading Symbol	ASH
Title of 12(b) Security	Common Stock, par value $.01 per share
Security Exchange Name	NYSE
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Entity Incorporation, State or Country Code	DE

STATEMENTS OF CONSOLIDATED COMP

STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (LOSS) (unaudited) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Sales	$ 552	$ 533
Cost of sales	374	380
Gross profit	178	153
Selling, general and administrative expense	106	99
Research and development expense	15	16
Intangibles amortization expense	21	21
Equity and other income	5	0
Operating income	41	17
Net interest and other expense (income)	(6)	10
Net income on divestitures	14	3
Income from continuing operations before income taxes	61	10
Income tax expense (benefit)	0	(24)
Income from continuing operations	61	34
Loss from discontinued operations (net of income taxes)	(5)	(2)
Net income	$ 56	$ 32
Basic earnings per share - Note M
Income from continuing operations	$ 1	$ 0.57
Income (loss) from discontinued operations	(0.08)	(0.03)
Net income	0.92	0.54
Diluted earnings per share - Note M
Income from continuing operations	0.99	0.56
Income (loss) from discontinued operations	(0.08)	(0.03)
Net income	$ 0.91	$ 0.53
COMPREHENSIVE INCOME (LOSS)
Net income	$ 56	$ 32
Other comprehensive income, net of tax
Unrealized translation gain	48	38
Other comprehensive income	48	38
Comprehensive income	$ 104	$ 70

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Millions		Dec. 31, 2020	Sep. 30, 2020
Current assets
Cash and cash equivalents		$ 335	$ 454
Accounts receivable	[1]	409	471
Inventories - Note F		537	529
Other assets		100	87
Current assets held for sale - Note B			6
Total current assets		1,381	1,547
Property, plant and equipment
Cost		3,310	3,265
Accumulated depreciation		1,748	1,700
Net property, plant and equipment		1,562	1,565
Goodwill - Note G		1,792	1,758
Intangibles - Note G		1,001	1,013
Operating lease assets, net - Note I		137	137
Restricted investments - Note E		316	301
Asbestos insurance receivable (b) - Note L	[2]	130	136
Deferred income taxes		26	26
Other assets		397	394
Total noncurrent assets		5,361	5,330
Total assets		6,742	6,877
Current liabilities
Short-term debt - Note H		93	280
Trade and other payables		217	233
Accrued expenses and other liabilities		252	277
Current operating lease obligations - Note I		23	23
Total current liabilities		585	813
Noncurrent liabilities
Long-term debt - Note H		1,601	1,573
Asbestos litigation reserve - Note L		498	513
Deferred income taxes		222	229
Employee benefit obligations - Note K		157	157
Operating lease obligations - Note I		124	124
Other liabilities		433	432
Total noncurrent liabilities		3,035	3,028
Commitments and contingencies - Note L
Stockholders’ equity		3,122	3,036
Total liabilities and stockholders' equity		$ 6,742	$ 6,877
[1]	Accounts receivable includes an allowance for credit losses of $3 million at both December 31, 2020 and September 30, 2020.
[2]	Asbestos insurance receivable includes an allowance for credit losses of $3 million at December 31, 2020.

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Current assets
Allowance for doubtful accounts	$ 3	$ 3
Insurance receivable allowance for credit losses	$ 3

STATEMENT OF CONSOLIDATED EQUIT

STATEMENT OF CONSOLIDATED EQUITY (Unaudited) - 3 months ended Dec. 31, 2020 - USD ($) $ in Millions		Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	[1]	Common stock [Member]	Paid-in capital [Member]	Retained earnings [Member]	Retained earnings [Member]Cumulative Effect, Period of Adoption, Adjustment [Member]	[1]	Accumulated other comprehensive income (loss) [Member]	[2]
Balance at Sep. 30, 2020		$ 3,036	$ (2)		$ 1	$ 769	$ 2,649	$ (2)		$ (383)
Accounting Standards Update [Extensible List]		us-gaap:NewAccountingPronouncementMember
COMPREHENSIVE INCOME (LOSS)
Net income		$ 56					56
Other comprehensive income		48								48
Regular dividends, $0.275 per common share		(17)					(17)
Common shares issued under stock incentive and other plans	[3]	1				1
Balance at Dec. 31, 2020		$ 3,122			$ 1	$ 770	$ 2,686			$ (335)
[1]	Represents the cumulative-effect adjustment, net of tax, for the adoption of the new accounting pronouncement related to the measurement of credit losses on financial instruments.
[2]	At December 31, 2020 and September 30, 2020, the after-tax accumulated other comprehensive loss of $335 million and $383 million, respectively, was each comprised of net unrealized translation losses of $333 million and $381 million, respectively, and unrecognized prior service costs as a result of certain employee benefit plan amendments of $2
[3]	Common shares issued were 99,194 for the three months ended December 31, 2020

STATEMENT OF CONSOLIDATED EQU_2

STATEMENT OF CONSOLIDATED EQUITY (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Sep. 30, 2020
Statement Of Stockholders Equity [Abstract]
Dividend per common share	$ 0.275
Accumulated other comprehensive loss	$ (335)	$ (383)
Unrecognized prior service costs	2	2
Net unrealized translation loss	$ (333)	$ (381)
Common shares issued (in shares)	99,194

STATEMENTS OF CONDENSED CONSOLI

STATEMENTS OF CONDENSED CONSOLIDATED CASH FLOWS (unaudited) - USD ($) $ in Millions		3 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
CASH FLOWS PROVIDED (USED) BY OPERATING ACTIVITIES FROM CONTINUING OPERATIONS
Net income		$ 56	$ 32
Loss from discontinued operations (net of income taxes)		5	2
Adjustments to reconcile income from continuing operations to cash flows from operating activities
Depreciation and amortization		62	61
Original issue discount and debt issuance costs amortization		1	2
Deferred income taxes		(5)	(12)
Gain from sales of property and equipment		(4)
Stock based compensation expense		4	4
Income from restricted investments		(23)	(13)
Net income on divestitures		(14)	(3)
Impairments		9
Pension contributions		(2)	(1)
Change in operating assets and liabilities	[1]	17	(109)
Total cash flows provided (used) by operating activities from continuing operations		106	(34)
CASH FLOWS PROVIDED (USED) BY INVESTING ACTIVITIES FROM CONTINUING OPERATIONS
Additions to property, plant and equipment		(30)	(29)
Proceeds from disposal of property, plant and equipment		5
Proceeds from sale or restructuring of operations		14
Net purchase of funds restricted for specific transactions		(1)	(1)
Reimbursement from restricted investments		8	10
Proceeds from sales of securities		42	4
Purchase of securities		(42)	(4)
Total cash flows used by investing activities from continuing operations		(4)	(20)
CASH FLOWS PROVIDED (USED) BY FINANCING ACTIVITIES FROM CONTINUING OPERATIONS
Proceeds from (repayment of) short-term debt		(187)	14
Cash dividends paid		(17)	(16)
Stock based compensation employee withholding taxes paid in cash		(3)	(5)
Total cash flows used by financing activities from continuing operations		(207)	(7)
CASH PROVIDED (USED) BY CONTINUING OPERATIONS		(105)	(61)
Cash provided (used) by discontinued operations
Operating cash flows		(14)	(17)
Investing cash flows		(3)	2
Total cash provided (used) by discontinued operations		(17)	(15)
Effect of currency exchange rate changes on cash and cash equivalents		3	1
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		(119)	(75)
CASH AND CASH EQUIVALENTS - BEGINNING OF PERIOD		454	232
CASH AND CASH EQUIVALENTS - END OF PERIOD		$ 335	$ 157
[1]	Excludes changes resulting from operations acquired, sold or held for sale.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Significant Accounting Policies	NOTE A – SIGNIFICANT ACCOUNTING POLICIES Basis of presentation The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial reporting and Securities and Exchange Commission (SEC) regulations. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. These statements omit certain information and footnote disclosures required for complete annual financial statements and, therefore, should be read in conjunction with Ashland Global Holdings Inc. and consolidated subsidiaries (Ashland) Annual Report on Form 10-K for the fiscal year ended September 30, 2020. Results of operations for the period ended December 31, 2020 are not necessarily indicative of the expected results for the remaining quarters in the fiscal year. All amounts are presented in millions except per-share amounts. Ashland’s reportable segments include the consumer specialty businesses: Life Sciences and Personal Care & Household; the industrial specialty businesses: Specialty Additives and Performance Adhesives; and Intermediates and Solvents. Unallocated and Other includes corporate governance activities and certain legacy matters. For additional information, see Note Q. Use of estimates, risks and uncertainties The preparation of Ashland’s Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and the disclosures of contingent assets and liabilities. Significant items that are subject to such estimates and assumptions include, but are not limited to, long-lived assets (including goodwill and other intangible assets), income taxes and liabilities and receivables associated with asbestos litigation and environmental remediation. Although management bases its estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances, actual results could differ significantly from the estimates under different assumptions or conditions. Ashland’s results are affected by domestic and international economic, political, legislative, regulatory and legal actions. Economic conditions, such as recessionary trends, inflation, interest and monetary exchange rates, government fiscal policies and changes in the prices of certain key raw materials, can have a significant effect on operations. While Ashland maintains reserves for anticipated liabilities and carries various levels of insurance, Ashland could be affected by civil, criminal, regulatory or administrative actions, claims or proceedings relating to asbestos, environmental remediation or other matters. New accounting pronouncements A description of new U.S. GAAP accounting standards issued or adopted during the current year is required in interim financial reporting. A detailed listing of new accounting standards relevant to Ashland is included in the Annual Report on Form 10-K for the fiscal year ended September 30, 2020. The following standards relevant to Ashland were either issued or adopted in the current fiscal year or will become effective in a subsequent period. In June 2016, the FASB issued amended accounting guidance related to the measurement of credit losses on financial instruments. The amended accounting guidance changes the impairment model for most financial assets to require measurement and recognition of expected credit losses for financial assets held. This guidance became effective for Ashland on October 1, 2020. As a result, Ashland recorded a $3 million increase in its allowance for credit losses, primarily related to asbestos receivables, and a $2 million decrease to retained earnings, net of tax, reflecting the cumulative effect on retained earnings. Under the new expected credit loss model, Ashland records an allowance for credit losses inherent in its receivables from revenue transactions and reinsurance recoverables. The allowance for credit losses is a valuation account deducted from the amortized cost basis of the assets to present their net carrying value at the amount expected to be collected. Ashland estimates expected credit losses based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. When measuring expected credit losses, Ashland pools assets with similar country risk and credit risk characteristics. Each period the allowance for credit losses is adjusted through earnings to reflect expected credit losses over the remaining lives of the assets. For the three months ending December 31, 2020, no significant credit losses were incurred within the Statements of Consolidated Comprehensive Income (Loss).

Divestitures

Divestitures	3 Months Ended
	Dec. 31, 2020
Divestitures [Abstract]
Divestitures	NOTE B Composites and Marl facility On August 30, 2019, Ashland completed the sale of its Composites business (excluding the Maleic business) and butanediol manufacturing facility in Marl, Germany to INEOS Enterprises (INEOS). On September 30, 2020, Ashland completed the sale of its Maleic business to AOC. Net proceeds from the sale were approximately $98 million. Since this disposal group signifies a strategic shift in Ashland’s business and had a major effect of Ashland’s operations and financial results, the operating results and cash flows related to Composites and the Marl facility, including the Maleic business, have been reflected as discontinued operations in the Statements of Consolidated Comprehensive Income (Loss) and Statements of Condensed Consolidated Cash Flows. See Note C of the Notes to Condensed Consolidated Financial Statements for the results of operations for Composites and the Marl facility, including the Maleic business, for all periods presented. Subsequent to the completion of the sale, Ashland is providing certain transition services to INEOS for a fee. While the transition services are expected to vary in duration depending upon the type of service provided, Ashland expects to reduce certain costs as the transition services are completed. Ashland recognized transition service fee income of $3 million during the three months ended December 31, 2020 and 2019. Other manufacturing facility sales During the three months ended December 31, 2020, Ashland completed the sale of a Specialty Additives facility, the assets and liabilities of which were classified as held for sale as of September 30, 2020. Net proceeds from the sale were approximately $14 million in the current quarter ($20 million in total including a deposit received in fiscal year 2020) and the Company recognized a pre-tax gain of $14 million recorded within the Net income on divestitures caption in the Statements of Consolidated Comprehensive Income (Loss).

Discontinued Operations

Discontinued Operations	3 Months Ended
	Dec. 31, 2020
Discontinued Operations And Disposal Groups [Abstract]
Discontinued Operations	NOTE C– DISCONTINUED OPERATIONS Ashland has divested certain businesses that have qualified as discontinued operations. The operating results from these divested businesses and subsequent adjustments related to ongoing assessments of certain retained liabilities and tax items have been recorded within the discontinued operations caption in the Statements of Consolidated Comprehensive Income (Loss) for all periods presented. Components of amounts reflected in the Statements of Consolidated Comprehensive Income (Loss) related to discontinued operations are presented in the following table for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Income (loss) from discontinued operations (net of tax) Composites/Marl facility $ — $ — Valvoline — (1 ) Water Technologies — (1 ) Distribution (1 ) — Gain (loss) on disposal of discontinued operations (net of taxes) Composites/Marl facility (4 ) — $ (5 ) $ (2 ) The following table presents a reconciliation of the captions within Ashland's Statements of Consolidated Comprehensive Income (Loss) for the income (loss) from discontinued operations attributable to Composites and the Marl facility for the three months ended December 31, 2019. The Maleic business, which was sold during fiscal 2020 to AOC, was operated under the Composites business and Marl facility disposal group and is therefore reported in discontinued operations. Three months ended December 31 (In millions) 2019 Income (loss) from discontinued operations attributable to Composites/Marl facility Sales $ 12 Cost of sales (10 ) Selling, general and administrative expense (2 ) Equity and other income 2 Pretax income of discontinued operations 2 Income tax expense (2 ) Income from discontinued operations $ —

Restructuring Activities

Restructuring Activities	3 Months Ended
	Dec. 31, 2020
Restructuring And Related Activities [Abstract]
Restructuring Activities	NOTE D – RESTRUCTURING ACTIVITIES Company-wide restructuring activities Ashland periodically implements company-wide restructuring programs related to acquisitions, divestitures and other cost reduction programs in order to enhance profitability through streamlined operations and an improved overall cost structure. Fiscal 2020 and 2021 restructuring costs During the three months ended December 31, 2020 and 2019, Ashland incurred severance expense of $8 million and $3 million, respectively, attributable to executive management changes and business management changes within the organization. As of December 31, 2020, the severance reserve associated with this transition was $36 million. The following table details at December 31, 2020 and 2019, the amount of restructuring severance reserves related to this program. The severance reserves were primarily recorded within accrued expenses and other liabilities in the Condensed Consolidated Balance Sheet as of December 31, 2020 and December 31, 2019. (In millions) Severance costs Balance at of September 30, 2020 39 Restructuring reserve 8 Utilization (cash paid) (11 ) Balance at December 31, 2020 $ 36 (In millions) Severance costs Balance at of September 30, 2019 — Restructuring reserve 3 Utilization (cash paid) — Balance at December 31, 2019 $ 3 Fiscal 2018 restructuring costs During fiscal 2018, Ashland initiated a company-wide cost reduction program as a result of ongoing strategic asset plans and activities. As part of this restructuring program, Ashland announced a voluntary severance offer to certain qualifying employees that was formally approved during 2018. Additionally, during fiscal 2018, an involuntary program for employees was also initiated as part of the restructuring program. These programs resulted in additional severance expense of $1 million for the three months ended December 31, 2019 which was primarily recorded within the selling, general and administrative expense caption of the Statement of Consolidated Comprehensive Income (Loss). As of December 31, 2020, the severance reserve for the company-wide restructuring program was zero. The following table details at December 31, 2019, the amount of restructuring reserves related to the programs discussed above, and the related activity in these reserves during the three months ended December 31, 2019. The severance reserve was primarily recorded within accrued expenses and other liabilities in the Condensed Consolidated Balance Sheet as of December 31, 2019. (In millions) Severance costs Balance at of September 30, 2019 7 Restructuring reserve 1 Utilization (cash paid) (3 ) Balance at December 31, 2019 $ 5

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE E – FAIR VALUE MEASUREMENTS As required by U.S. GAAP, Ashland uses applicable guidance for defining fair value, the initial recording and periodic remeasurement of certain assets and liabilities measured at fair value and related disclosures for instruments measured at fair value. Fair value accounting guidance establishes a fair value hierarchy, which prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). An instrument’s categorization within the fair value hierarchy is based upon the lowest level of input that is significant to the instrument’s fair value measurement. The three levels within the fair value hierarchy are described as follows. Level 1 – Observable inputs such as unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 – Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. Level 3 – Unobservable inputs for the asset or liability for which there is little, if any, market activity at the measurement date. Unobservable inputs reflect Ashland’s own assumptions about what market participants would use to price the asset or liability. The inputs are developed based on the best information available in the circumstances, which might include Ashland’s own financial data such as internally developed pricing models, discounted cash flow methodologies, as well as instruments for which the fair value determination requires significant management judgment. For assets that are measured using quoted prices in active markets (Level 1), the total fair value is the published market price per unit multiplied by the number of units held without consideration of transaction costs. Assets and liabilities that are measured using significant other observable inputs (Level 2) are primarily valued by reference to quoted prices of similar assets or liabilities in active markets, adjusted for any terms specific to that asset or liability. For all other assets and liabilities for which unobservable inputs are used (Level 3), fair value is derived using fair value models, such as a discounted cash flow model or other standard pricing models that Ashland deems reasonable. The following table summarizes financial instruments subject to recurring fair value measurements as of December 31, 2020. Carrying Total fair Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs (In millions) value value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 335 $ 335 $ 335 $ — $ — Restricted investments (a) 346 346 346 — — Investment of captive insurance company (b) 8 8 8 — — Total assets at fair value $ 689 $ 689 $ 689 $ — $ — Liabilities Foreign currency derivatives $ 1 $ 1 $ — $ 1 $ — (a) Included in restricted investments is $30 million classified in the other current assets caption on the Condensed Consolidated Balance Sheets. (b) Included in other noncurrent assets in the Condensed Consolidated Balance Sheets. The following table summarizes financial asset instruments subject to recurring fair value measurements as of September 30, 2020. Carrying Total fair Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs (In millions) value value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 454 $ 454 $ 454 $ — $ — Restricted investments (a) 331 331 331 — — Investment of captive insurance company (b) 9 9 9 — — Foreign currency derivatives 1 1 — 1 — Total assets at fair value $ 795 $ 795 $ 794 $ 1 $ — Liabilities Foreign currency derivatives $ 3 $ 3 $ — $ 3 $ — (a) Included in restricted investments is $30 million classified in the other current assets caption on the Condensed Consolidated Balance Sheets. (b) Included in other noncurrent assets in the Condensed Consolidated Balance Sheets. Restricted investments Investment income and realized gains and losses on these company-restricted investments are reported within the net interest and other expense caption on the Statements of Consolidated Comprehensive Income (Loss). The following table provides a summary of the activity within the investment portfolio as of December 31, 2020 and September 30, 2020: (In millions) December 31 2020 September 30 2020 Original cost $ 335 $ 335 Accumulated adjustments, net (a) (50 ) (30 ) Adjusted cost, beginning of year 285 305 Investment income (b) 5 10 Net unrealized gain (c) 52 46 Realized gains (c) 11 2 Settlement funds 1 3 Disbursements (8 ) (35 ) Fair value $ 346 $ 331 (a) The accumulated adjustments include investment income, realized gains, disbursements and settlements recorded in previous periods. (b) Investment income for the demand deposit includes interest income as well as dividend income transferred from the equity and fixed income mutual funds. (c) Presented under the original cost method. The following table presents gross unrealized gains and losses for the restricted investment securities as of December 31, 2020 and September 30, 2020: Gross Gross (In millions) Adjusted Cost Unrealized Gain Unrealized Loss Fair Value As of December 31, 2020 Demand deposit $ 9 $ — $ — $ 9 Equity mutual fund 101 38 — 139 Fixed income mutual fund 184 14 — 198 $ 294 $ 52 $ — $ 346 As of September 30, 2020 Demand deposit $ 7 $ — $ — $ 7 Equity mutual fund 116 31 (1 ) 146 Fixed income mutual fund 162 16 — 178 $ 285 $ 47 $ (1 ) $ 331 The following table presents the investment income, net gains and losses realized and disbursements related to the investments within the portfolio for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Investment income $ 5 $ 4 Net gains (losses) unrealized (a) 18 9 Disbursements (8 ) (10 ) (a) Ashland determined that all unrealized gains and (losses) were related to equity securities with readily determinable fair values. Due to the new accounting guidance adopted in the first quarter of fiscal year 2019, the net unrealized gains and (losses) during the year ended September 30, 2019 and forward were recorded within the net interest and other expense caption in the Statements of Consolidated Income (Loss). Foreign currency derivatives Ashland conducts business in a variety of foreign currencies. Accordingly, Ashland regularly uses foreign currency derivative instruments to manage exposure on certain transactions denominated in foreign currencies to curtail potential earnings volatility effects on certain assets and liabilities, including short-term inter-company loans, denominated in currencies other than Ashland’s functional currency of an entity. These derivative contracts generally require exchange of one foreign currency for another at a fixed rate at a future date and generally have maturities of less than twelve months. All contracts are valued at fair value with net changes in fair value recorded within the selling, general and administrative expense caption. The impacts of these contracts were largely offset by gains and losses resulting from the impact of changes in exchange rates on transactions denominated in non-functional currencies. The following table summarizes the net gains and losses recognized during the three months ended December 31, 2020 and 2019 within the Statements of Consolidated Comprehensive Income (Loss). Three months ended December 31 (In millions) 2020 2019 Foreign currency derivative gains (losses) $ 3 $ 1 The following table summarizes the fair values of the outstanding foreign currency derivatives as of December 31, 2020 and September 30, 2020 included in accounts receivable and accrued expenses and other liabilities of the Condensed Consolidated Balance Sheets. December 31 September 30 (In millions) 2020 2020 Foreign currency derivative assets $ — $ 1 Notional contract values 168 170 Foreign currency derivative liabilities $ 1 $ 3 Notional contract values 221 215 Other financial instruments At December 31, 2020 and September 30, 2020, Ashland's long-term debt (including the current portion and excluding debt issuance cost discounts) had a carrying value of $1,616 million and $1,588 million, respectively, compared to a fair value of $1,806 million and $1,708 million, respectively. The fair values of long-term debt are based on quoted market prices or, if market prices are not available, the present values of the underlying cash flows discounted at Ashland’s incremental borrowing rates.

Inventories

Inventories	3 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Inventories	NOTE F – INVENTORIES Inventories are carried at the lower of cost or net realizable value. Inventories are primarily stated at cost using the weighted-average cost method. In addition, certain inventories are valued at cost using the last-in, first-out (LIFO) method. The following table summarizes Ashland’s inventories as of the reported Condensed Consolidated Balance Sheet dates. (In millions) December 31, 2020 September 30, 2020 Finished products $ 341 $ 336 Raw materials, supplies and work in process 196 193 $ 537 $ 529

Goodwill and Other Intangibles

Goodwill and Other Intangibles	3 Months Ended
	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangibles	NOTE G – GOODWILL AND OTHER INTANGIBLES Goodwill Ashland tests goodwill and other indefinite-lived intangible assets for impairment annually as of July 1 and when events and circumstances indicate an impairment may have occurred. Ashland tests goodwill and other indefinite-lived intangible assets for impairment by comparing the estimated fair value of the reporting units (for goodwill) and other indefinite-lived intangible assets to the related carrying value. If the carrying amount of a reporting unit or other indefinite-lived intangible asset exceeds its estimated fair value, Ashland records an impairment loss based on the difference between fair value and carrying amount, in the case of reporting units, not to exceed to the associated carrying amount of goodwill. Ashland’s assessment of an impairment on any of these assets classified currently as having indefinite lives, including goodwill, could change in future periods if significant events happen and/or circumstances change that effect the previously mentioned assumptions such as: a significant change in projected business results, a divestiture decision, increase in Ashland’s weighted-average cost of capital rates, decrease in growth rates or assumptions, economic deterioration that is more severe or of a longer duration than anticipated, or another significant economic event. Ashland’s reporting units align with its reportable segments. Ashland determined that its reporting units are Life Sciences, Personal Care & Household, Specialty Additives, Performance Adhesives, and Intermediates and Solvents. N o indicators of impairment were identified in the first quarter of Fiscal 2021. The following is a progression of goodwill by reportable segment for the three months ended December 31, 2020. (In millions) Life Sciences Personal Care & Household (a) Specialty Additives (a) Performance Adhesives Intermediates and Solvents (a) Total Balance at September 30, 2020 $ 861 $ — $ 444 $ 453 $ — $ 1,758 Currency translation 21 — 13 — — 34 Balance at December 31, 2020 $ 882 $ — $ 457 $ 453 $ — $ 1,792 (a) As of December 31, 2020 a nd September 30, 2020 , t here w ere accumulated impairment s of $ 356 million, $ 174 million and $ 90 million related to the Personal Care & Household, Specialty Additives and Intermediates and Solvents reportable segment s, respectively . Other intangible assets Intangible assets principally consist of trademarks and trade names, intellectual property and customer and supplier relationships. Intangible assets classified as finite are amortized on a straight-line basis over their estimated useful lives. The cost of trademarks and trade names is amortized principally over 3 to 25 years, intellectual property over 5 to 25 years, and customer and supplier relationships over 3 to 24 years. Ashland annually reviews, as of July 1, indefinite-lived intangible assets for possible impairment or whenever events or changes in circumstances indicate that carrying amounts may not be recoverable. Trademarks and trade names are valued using a “relief-from-royalty” valuation method compared to the carrying value. No indicators of impairment were identified in the first quarter of Fiscal 2021. Intangible assets were comprised of the following as of December 31, 2020 and September 30, 2020. December 31, 2020 Gross Net carrying Accumulated carrying (In millions) amount amortization amount Definite-lived intangibles Trademarks and trade names $ 66 $ (33 ) $ 33 Intellectual property 731 (460 ) 271 Customer and supplier relationships 770 (351 ) 419 Total definite-lived intangibles 1,567 (844 ) 723 Indefinite-lived intangibles Trademarks and trade names 278 — 278 Total intangible assets $ 1,845 $ (844 ) $ 1,001 September 30, 2020 Gross Net carrying Accumulated carrying (In millions) amount amortization amount Definite-lived intangibles Trademarks and trade names $ 66 $ (32 ) $ 34 Intellectual property 721 (442 ) 279 Customer and supplier relationships 757 (335 ) 422 Total definite-lived intangibles 1,544 (809 ) 735 Indefinite-lived intangibles Trademarks and trade names 278 — 278 Total intangible assets $ 1,822 $ (809 ) $ 1,013 Amortization expense recognized on intangible assets was

Debt

Debt	3 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Debt	NOTE H – DEBT The following table summarizes Ashland’s current and long-term debt as of the dates reported in the Condensed Consolidated Balance Sheets. (In millions) December 31, 2020 September 30, 2020 4.750% notes, due 2022 $ 411 $ 411 2.00% Senior Notes, due 2028 (Euro 500 million principal) 614 587 6.875% notes, due 2043 282 282 Term loan A 250 250 Accounts receivable securitizations 69 177 6.50% junior subordinated notes, due 2029 55 55 Revolving credit facility — 80 Other (a) 13 11 Total debt 1,694 1,853 Short-term debt (includes current portion of long-term debt) (93 ) (280 ) Long-term debt (less current portion) $ 1,601 $ 1,573 (a) Includes $15 million of debt issuance cost discounts as of both December 31, 2020 and September 30, 2020. Additionally, as of December 31, 2020 and September 30, 2020, Other includes a European short-term loan facility with an outstanding balance of $24 million and $23 million, respectively. The scheduled aggregate maturities of long-term debt by year (including the current portion and excluding debt issuance costs) are as follows as of December 31, 2020: zero remaining in 2021, $421 million in 2022, $22 million in 2023, $44 million in 2024 and $175 million in 2025. Available borrowing capacity The borrowing capacity remaining under the 2020 $600 million Revolving Credit Facility was $580 million due to a reduction of $20 million for letters of credit outstanding as of December 31, 2020. Ashland's total borrowing capacity at December 31, 2020 was $694 million, which included $114 million of available capacity from the two accounts receivable securitization facilities. Covenants related to current Ashland debt agreements Ashland's debt contains usual and customary representations, warranties and affirmative and negative covenants, including financial covenants for leverage and interest coverage ratios, limitations on liens, additional subsidiary indebtedness, restrictions on subsidiary distributions, investments, mergers, sale of assets and restricted payments and other customary limitations. As of December 31, 2020, Ashland is in compliance with all debt agreement covenant restrictions. The maximum consolidated net leverage ratio permitted under Ashland's most recent credit agreement (the 2020 Credit Agreement) is 4.0. At December 31, 2020, Ashland’s calculation of the consolidated net leverage ratio was 2.6. The minimum required consolidated interest coverage ratio under the 2020 Credit Agreement during its entire duration is 3.0. At December 31, 2020, Ashland’s calculation of the interest coverage ratio was 7.8.

Leasing Arrangements

Leasing Arrangements	3 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leasing Arrangements	NOTE I – LEASING ARRANGEMENTS Ashland determines if an arrangement is or contains a lease at contract inception and determines its classification as an operating or finance lease at lease commencement. Ashland leases certain office buildings, transportation equipment, warehouses and storage facilities, and equipment. All of Ashland’s leases are operating leases. Real estate leases represent approximately 89% of the total lease liability. Operating lease assets and obligations are reflected within operating lease assets, net; current operating lease obligations; and non-current operating lease obligations captions on the Condensed Consolidated Balance Sheets. Lease expense for these leases is recognized on a straight-line basis over the lease term, with variable lease payments recognized in the period those payments are incurred. The components of lease cost recognized within our Statements of Consolidated Comprehensive Income (Loss) were as follows: Three months ended December 31 (In millions) Location 2020 2019 Lease cost: Operating lease cost Selling, General & Administrative $ 3 $ 5 Operating lease cost Cost of Sales 4 4 Variable lease cost Cost of Sales 1 1 Short-term leases Cost of Sales 1 — Total lease cost $ 9 $ 10 The following table summarizes Ashland’s lease assets and liabilities as presented in the Condensed Consolidated Balance Sheet: (In millions) December 31, 2020 September 30, 2020 Assets Operating lease assets, net $ 137 $ 137 Total lease assets 137 137 Liabilities Current operating lease obligations $ 23 $ 23 Non-current operating lease obligations 124 124 Total lease liabilities $ 147 $ 147 Ashland often has options to renew lease terms for buildings and other assets. The exercise of lease renewal options are generally at Ashland’s sole discretion. In addition, certain lease arrangements may be terminated prior to their original expiration date at Ashland’s discretion. Ashland evaluates renewal and termination options at the lease commencement date to determine if it is reasonably certain to exercise the option on the basis of economic factors. The weighted average remaining lease term for operating leases as of December 31, 2020 and September 30, 2020 was approximately 15 years Residual value guarantees are not common within Ashland’s lease agreements nor are restrictions or covenants imposed by leases. Ashland has elected the practical expedient to combine lease and non-lease components. The discount rate implicit within the leases is generally not determinable. Therefore, Ashland determines the discount rate based on its incremental borrowing rate. The incremental borrowing rate is determined using a buildup method resulting in an estimated range of secured borrowing rates matching the lease term and the currency of the jurisdiction in which lease payments are made, adjusted for impacts of collateral. Consideration was given to Ashland’s own relevant debt issuances as well as debt instruments of comparable companies with similar credit characteristics. The weighted average discount rate used to measure operating lease liabilities as of December 31, 2020 and September 30, 2020 was 2.9%. There are no leases that have not yet commenced but that create significant rights and obligations for Ashland. Right-of-use assets exchanged for new operating lease obligations were $ 2 Cash paid for amounts included in the measurement of operating lease liabilities: Three months ended December 31 (In millions) 2020 2019 Operating cash flows from operating leases $ 7 $ 9 Maturity Analysis of Lease Liabilities Maturities of lease liabilities are shown below as of December 31, 2020 and September 30, 2020: (In millions) December 31, 2020 September 30, 2020 Remainder of 2021 $ 20 $ 28 2022 37 35 2023 17 17 2024 14 13 2025 12 11 Thereafter $ 90 $ 88 Total lease payments 190 192 Less amount of lease payment representing interest (43 ) (45 ) Total present value of lease payments $ 147 $ 147

Income Taxes

Income Taxes	3 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	NOTE J – INCOME TAXES Current fiscal year Ashland’s effective tax rate in any interim period is subject to adjustments related to discrete items and the mix of domestic and foreign operating results. The overall effective tax rate was zero for the three months ended December 31, 2020. Prior fiscal year The overall effective tax rate was a benefit of 240% for the three months ended December 31, 2019. The quarter tax rate was primarily impacted by jurisdictional income mix, as well as $27 million from favorable tax discrete items primarily related to the Swiss Tax Reform. Unrecognized tax benefits Changes in unrecognized tax benefits are summarized as follows for the three months ended December 31, 2020. (In millions) Balance at October 1, 2020 $ 171 Increases related to positions taken in the current year 7 Balance at December 31, 2020 $ 178 From a combination of statute expirations and audit settlements in the next twelve months, Ashland expects a decrease in the amount accrued for uncertain tax positions of between $50 million and $60 million for continuing operations. It is reasonably possible that there could be other material changes to the amount of uncertain tax positions due to activities of the taxing authorities, settlement of audit issues or the reassessment of existing uncertain tax positions; however, Ashland is not able to estimate the impact of these items at this time.

Employee Benefit Plans

Employee Benefit Plans	3 Months Ended
	Dec. 31, 2020
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plans	NOTE K - EMPLOYEE BENEFIT PLANS Plan contributions For the three months ended December 31, 2020, Ashland contributed $2 million to its non-U.S. pension plans and zero to its U.S. pension plans. Ashland expects to make additional contributions of approximately $3 million to its non-U.S. plans and $2 million to its U.S. pension plans during the remainder of fiscal 2021. Components of net periodic benefit costs (income) The following table details the components of pension and other postretirement benefit costs for continuing operations. Pension benefits Other postretirement benefits (In millions) 2020 2019 2020 2019 Three months ended December 31 Service cost $ 1 $ 1 $ — $ — Interest cost 2 2 — 1 Expected return on plan assets (2 ) (3 ) — — Curtailment — — — — Total net periodic benefit costs $ 1 $ — $ — $ 1 For segment reporting purposes, service cost is proportionately allocated to each segment, excluding the Unallocated and other segment, and is recorded within the selling, general and administrative expense and cost of sales captions on the Statements of Consolidated Comprehensive Loss (Income). All other components are recorded within the other net periodic benefit income caption on the Statements of Consolidated Comprehensive Loss (Income).

Litigation, Claims and Continge

Litigation, Claims and Contingencies	3 Months Ended
	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Litigation, Claims and Contingencies	NOTE L Asbestos litigation Ashland is subject to liabilities from claims alleging personal injury caused by exposure to asbestos. Such claims result from indemnification obligations undertaken in 1990 in connection with the sale of Riley Stoker Corporation (Riley) and the acquisition of Hercules in November 2008. Although Riley, a former subsidiary, was neither a producer nor a manufacturer of asbestos, its industrial boilers contained some asbestos-containing components provided by other companies. Hercules, an indirect wholly-owned subsidiary of Ashland, has liabilities from claims alleging personal injury caused by exposure to asbestos. Such claims typically arise from alleged exposure to asbestos fibers from resin encapsulated pipe and tank products sold by one of Hercules’ former subsidiaries to a limited industrial market. To assist in developing and annually updating independent reserve estimates for future asbestos claims and related costs given various assumptions for Ashland and Hercules asbestos claims, Ashland retained Nathan Associates Inc. (Nathan). The methodology used by Nathan to project future asbestos costs is based largely on recent experience, including claim-filing and settlement rates, disease mix, enacted legislation, open claims and litigation defense. The claim experience of Ashland and Hercules are separately compared to the results of previously conducted third party epidemiological studies estimating the number of people likely to develop asbestos-related diseases. Those studies were undertaken in connection with national analyses of the population expected to have been exposed to asbestos. Using that information, Nathan estimates a range of the number of future claims that may be filed, as well as the related costs that may be incurred in resolving those claims. Changes in asbestos-related liabilities and receivables are recorded on an after-tax basis within the discontinued operations caption in the Statements of Consolidated Comprehensive Income (Loss). Ashland asbestos-related litigation The claims alleging personal injury caused by exposure to asbestos asserted against Ashland result primarily from indemnification obligations undertaken in 1990 in connection with the sale of Riley. The amount and timing of settlements and number of open claims can fluctuate from period to period. A summary of Ashland asbestos claims activity, excluding Hercules claims, follows. Three months ended December 31 Years ended September 30 (In thousands) 2020 2019 2020 2019 2018 Open claims - beginning of year 49 53 53 53 54 New claims filed 1 — 2 2 2 Claims settled — — (1 ) (1 ) (1 ) Claims dismissed (1 ) (2 ) (5 ) (1 ) (2 ) Open claims - end of period 49 51 49 53 53 Ashland asbestos-related liability From the range of estimates, Ashland records the amount it believes to be the best estimate of future payments for litigation defense and claim settlement costs, which generally approximates the mid-point of the estimated range of exposure from model results. Ashland reviews this estimate and related assumptions quarterly and annually updates the results of a non-inflated, non-discounted approximate 50-year model developed with the assistance of Nathan. During the most recent annual update of this estimate completed during fiscal year 2020, it was determined that the liability for Ashland asbestos-related claims should be increased by $13 million. Total reserves for asbestos claims were $325 million at December 31, 2020 compared to $335 million at September 30, 2020. A progression of activity in the asbestos reserve is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Asbestos reserve - beginning of year $ 335 $ 352 $ 352 $ 380 $ 419 Reserve adjustment — — 13 1 (8 ) Amounts paid (10 ) (10 ) (30 ) (29 ) (31 ) Asbestos reserve - end of period (a) $ 325 $ 342 $ 335 $ 352 $ 380 (a) Included $ million classified in accrued expenses and other liabilities on the Condensed Consolidated Balance Sheets as of both December 31, 2020 and September 30, 2020 . Ashland asbestos-related receivables Ashland has insurance coverage for certain litigation defense and claim settlement costs incurred in connection with its asbestos claims, and coverage-in-place agreements exist with the insurance companies that provide substantially all of the coverage that will be accessed. For the Ashland asbestos-related obligations, Ashland has estimated the value of probable insurance recoveries associated with its asbestos reserve based on management’s interpretations and estimates surrounding the available or applicable insurance coverage, including an assumption that all solvent insurance carriers remain solvent. A substantial portion of the estimated receivables from insurance companies are expected to be due from domestic insurers. At December 31, 2020, Ashland’s receivable for recoveries of litigation defense and claim settlement costs from insurers amounted to $98 million (excluding the Hercules receivable for asbestos claims) compared to $103 million at September 30, 2020. During fiscal year 2020, the annual update of the model used for purposes of valuing the asbestos reserve and its impact on valuation of future recoveries from insurers was completed. This model update resulted in a $1 million increase in the receivable for probable insurance recoveries. A progression of activity in the Ashland insurance receivable is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Insurance receivable - beginning of year $ 103 $ 123 $ 123 $ 140 $ 155 Receivable adjustment (a) (2 ) — 1 (5 ) (5 ) Insurance settlement — — (10 ) — — Amounts collected (3 ) (1 ) (11 ) (12 ) (10 ) Insurance receivable - end of period (b) $ 98 $ 122 $ 103 $ 123 $ 140 (a) The three months ended December 31, 2020 includes a $2 million adjustment related to allowances for credit losses as a result of Ashland’s adoption of the new credit measurement standard described in Note A. ( b ) Included Hercules asbestos-related litigation Hercules has liabilities from claims alleging personal injury caused by exposure to asbestos. Such claims typically arise from alleged exposure to asbestos fibers from resin encapsulated pipe and tank products which were sold by one of Hercules’ former subsidiaries to a limited industrial market. The amount and timing of settlements and number of open claims can fluctuate from period to period. A summary of Hercules’ asbestos claims activity follows. Three months ended December 31 Years ended September 30 (In thousands) 2020 2019 2020 2019 2018 Open claims - beginning of year 12 13 13 13 12 New claims filed 1 — 1 1 2 Claims dismissed (1 ) — (2 ) (1 ) (1 ) Open claims - end of period 12 13 12 13 13 Hercules asbestos-related liability From the range of estimates, Ashland records the amount it believes to be the best estimate of future payments for litigation defense and claim settlement costs, which generally approximates the mid-point of the estimated range of exposure from model results. Ashland reviews this estimate, and related assumptions quarterly and annually updates the results of a non-inflated, non-discounted approximate 50-year model developed with the assistance of Nathan. As a result of the most recent annual update of this estimate, completed during fiscal year 2020, it was determined that the liability for Hercules asbestos-related claims should be decreased by $ 3 million. Total reserves for asbestos claims were $ 224 million at December 31, 2020 compared to $229 million at September 30, 2020 . A progression of activity in the asbestos reserve is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Asbestos reserve - beginning of year $ 229 $ 252 $ 252 $ 282 $ 323 Reserve adjustments — — (3 ) (10 ) (19 ) Amounts paid (5 ) (5 ) (20 ) (20 ) (22 ) Asbestos reserve - end of period (a) $ 224 $ 247 $ 229 $ 252 $ 282 (a) Included Hercules asbestos-related receivables For the Hercules asbestos-related obligations, certain reimbursement obligations pursuant to coverage-in-place agreements with insurance carriers exist. Ashland has estimated the value of probable insurance recoveries associated with its asbestos reserve based on management’s interpretations and estimates surrounding the available or applicable insurance coverage, including an assumption that all solvent insurance carriers remain solvent. The estimated receivable consists exclusively of solvent domestic insurers. As of December 31, 2020, Ashland’s receivable for recoveries of litigation defense and claims costs from insurers with respect to Hercules amounted to $46 million. During fiscal year 2020, the annual update of the model used for purposes of valuing the asbestos reserve and its impact on valuation of future recoveries from insurers was completed. This model update resulted in a decrease of $2 million in the receivable for probable insurance recoveries. A progression of activity in the Hercules insurance receivable is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Insurance receivable - beginning of year $ 47 $ 49 $ 49 $ 54 $ 68 Receivable adjustment (a) (1 ) — (2 ) (5 ) (14 ) Insurance receivable - end of period $ 46 $ 49 $ 47 $ 49 $ 54 (a) The three months ended December 31, 2020 includes a $1 million adjustment related to allowances for credit losses as a result of Ashland’s adoption of the new credit measurement standard described in Note A Asbestos litigation cost projection Projecting future asbestos costs is subject to numerous variables that are extremely difficult to predict. In addition to the significant uncertainties surrounding the number of claims that might be received, other variables include the type and severity of the disease alleged by each claimant, the long latency period associated with asbestos exposure, mortality rates, dismissal rates, costs of medical treatment, the impact of bankruptcies of other companies that are co-defendants in claims, uncertainties surrounding the litigation process from jurisdiction to jurisdiction and from case to case, and the impact of potential changes in legislative or judicial standards. Furthermore, any predictions with respect to these variables are subject to even greater uncertainty as the projection period lengthens. Considering these inherent uncertainties, Ashland believes that the asbestos reserves for Ashland and Hercules represent the best estimate within a range of possible outcomes. As a part of the process to develop these estimates of future asbestos costs, a range of long-term cost models was developed. These models are based on national studies that predict the number of people likely to develop asbestos-related diseases and are heavily influenced by assumptions regarding long-term inflation rates for indemnity payments and legal defense costs, as well as other variables mentioned previously. Ashland has currently estimated in various models ranging from approximately 40 to 50 year periods that it is reasonably possible that total future litigation defense and claim settlement costs on an inflated and undiscounted basis could range as high as approximately $520 million for the Ashland asbestos-related litigation (current reserve of $325 million) and approximately $350 million for the Hercules asbestos-related litigation (current reserve of $224 million), depending on the combination of assumptions selected in the various models. If actual experience is worse than projected, relative to the number of claims filed, the severity of alleged disease associated with those claims or costs incurred to resolve those claims, or actuarial refinement or improvements to the assumptions used within these models are initiated, Ashland may need to further increase the estimates of the costs associated with asbestos claims and these increases could be material over time. Environmental remediation and asset retirement obligations Ashland is subject to various federal, state and local environmental laws and regulations that require environmental assessment or remediation efforts (collectively, environmental remediation) at multiple locations. At December 31, 2020, such locations included 82 waste treatment or disposal sites where Ashland has been identified as a potentially responsible party under Superfund or similar state laws, 113 current and former operating facilities (including certain operating facilities conveyed as part of previous divestitures) and about 1,225 service station properties, of which 24 are being actively remediated. Ashland’s reserves for environmental remediation and related environmental litigation amounted to $195 million at December 31, 2020 compared to $200 million at September 30, 2020, of which $145 million at December 31, 2020 and $150 million at September 30, 2020 were classified in other noncurrent liabilities on the Condensed Consolidated Balance Sheets. The remaining reserves were classified in accrued expenses and other liabilities on the Condensed Consolidated Balance Sheets. The following table provides a reconciliation of the changes in the environmental remediation reserves during the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Reserve - beginning of period $ 200 $ 186 Disbursements (10 ) (9 ) Revised obligation estimates and accretion 5 2 Reserve - end of period $ 195 $ 179 The total reserves for environmental remediation reflect Ashland’s estimates of the most likely costs that will be incurred over an extended period to remediate identified conditions for which the costs are reasonably estimable, without regard to any third-party recoveries. Engineering studies, probability techniques, historical experience and other factors are used to identify and evaluate remediation alternatives and their related costs in determining the estimated reserves for environmental remediation. Ashland continues to discount certain environmental sites and regularly adjusts its reserves as environmental remediation continues. Ashland has estimated the value of its probable insurance recoveries associated with its environmental reserve based on management’s interpretations and estimates surrounding the available or applicable insurance coverage. At December 31, 2020 and September 30, 2020 , Ashland’s recorded receivable for these probable insurance recoveries was $ million, of which $ 12 million at December 31, 2020 and September 30, 2020 was classified in other noncurrent assets on the Condensed Consolidated Balance Sheets. Components of environmental remediation expense included within the selling, general and administrative expense caption of the Statements of Consolidated Comprehensive Income (Loss) are presented in the following table for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Environmental expense $ 5 $ 2 Accretion — — Legal expense 1 2 Total expense 6 4 Insurance receivable (1 ) — Total expense, net of receivable activity (a) $ 5 $ 4 (a) Net expense of $1 million for the three months ended December 31, 2020, relates to divested businesses which qualified for treatment as discontinued operations for which certain environmental liabilities were retained by Ashland. These amounts are classified within the income from discontinued operations caption of the Statements of Consolidated Comprehensive Income (loss). Environmental remediation reserves are subject to numerous inherent uncertainties that affect Ashland’s ability to estimate its share of the costs. Such uncertainties involve the nature and extent of contamination at each site, the extent of required cleanup efforts under existing environmental regulations, widely varying costs of alternate cleanup methods, changes in environmental regulations, the potential effect of continuing improvements in remediation technology, and the number and financial strength of other potentially responsible parties at multiparty sites. Although it is not possible to predict with certainty the ultimate costs of environmental remediation, Ashland currently estimates that the upper end of the reasonably possible range of future costs for identified sites could be as high as approximately $470 million. The largest reserve for any site is 14% of the remediation reserve. Other legal proceedings and claims In addition to the matters described above, there are other various claims, lawsuits and administrative proceedings pending or threatened against Ashland and its current and former subsidiaries. Such actions are with respect to commercial matters, product liability, toxic tort liability, and other environmental matters, which seek remedies or damages, some of which are for substantial amounts. While Ashland cannot predict with certainty the outcome of such actions, it believes that adequate reserves have been recorded and losses already recognized with respect to such actions were immaterial as of December 31, 2020 and September 30, 2020. There is a reasonable possibility that a loss exceeding amounts already recognized may be incurred related to these actions; however, Ashland believes that such potential losses were immaterial as of December 31, 2020.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Share	NOTE M The following is the computation of basic and diluted earnings per share (EPS) from continuing operations attributable to Ashland. Stock appreciation rights (SARs), stock options and warrants available to purchase shares outstanding for each reporting period whose grant price was greater than the average market price of Ashland Common Stock for each applicable period were not included in the computation of income from continuing operations per diluted share because the effect of these instruments would be antidilutive. The total number of these shares outstanding was approximately Three months ended December 31 (In millions, except per share data) 2020 2019 Numerator Numerator for basic and diluted EPS - Income (loss) from continuing operations $ 61 $ 34 Denominator Denominator for basic EPS - Weighted- average common shares outstanding 60 60 Share based awards convertible to common shares 1 1 Denominator for diluted EPS - Adjusted weighted- average shares and assumed conversions 61 61 EPS from continuing operations Basic $ 1.00 $ 0.57 Diluted 0.99 0.56

Equity Items

Equity Items	3 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Equity Items	NOTE N Stockholder dividends Dividends of 27.5 cents per share were paid in the first quarter of fiscal 2021 and fiscal 2020. Accumulated other comprehensive income (loss) Components of other comprehensive income (loss) recorded in the Statements of Consolidated Comprehensive Income (Loss) are presented below, before tax and net of tax effects. 2020 2019 (In millions) Before tax Tax (expense) benefit Net of tax Before tax Tax (expense) benefit Net of tax Three months ended December 31 Other comprehensive income (loss) Unrealized translation gain $ 48 $ — $ 48 $ 38 $ — $ 38 Total other comprehensive income $ 48 $ — $ 48 $ 38 $ — $ 38 Summary of stockholders’ equity A reconciliation of changes in stockholders’ equity are as follows: Three months ended December 31 (In millions) 2020 2019 Common stock and paid in capital Balance, beginning of period $ 770 $ 757 Common shares issued under stock incentive and other plans (a) 1 1 Balance, end of period 771 758 Retained earnings Balance, beginning of period 2,649 3,224 Adoption of new accounting pronouncements (2 ) — Net income 56 32 Regular dividends (17 ) (17 ) Balance, end of period 2,686 3,239 Accumulated other comprehensive income (loss) Balance, beginning of period (383 ) (410 ) Unrealized translation gain 48 38 Balance, end of period (335 ) (372 ) Total stockholders' equity $ 3,122 $ 3,625 Cash dividends declared per common share $ 0.275 $ 0.275 (a) Common shares issued were 99,194 shares and 70,461 shares for the three months ended December 31, 2020 and 2019, respectively.

Stock Incentive Plans

Stock Incentive Plans	3 Months Ended
	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Incentive Plans	NOTE O – STOCK INCENTIVE PLANS The components of Ashland’s pre-tax stock-based compensation expense included in continuing operations are as follows: Three months ended December 31 (In millions) 2020 (a) 2019 (b) SARs $ 1 $ 2 Nonvested stock awards 2 2 Performance share awards 2 1 $ 5 $ 5 (a) Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2020. (b) Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2019.

Revenue

Revenue	3 Months Ended
	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Revenue	NOTE P – REVENUE Revenue recognition Ashland’s revenue is measured as the amount of consideration it expects to receive in exchange for transferring goods or providing services and is recognized when performance obligations are satisfied under the terms of contracts with customers. Ashland generally utilizes standardized language for the terms of contracts, unless a separate agreement has been entered into with a customer that supersedes the standard language. A performance obligation is deemed to be satisfied by Ashland when control of the product or service is transferred to the customer. The transaction price of a contract, or the amount Ashland expects to receive upon satisfaction of all performance obligations, is determined by reference to the contract’s terms and includes adjustments, if applicable, for any variable consideration, such as volume discounts, rebates, refunds and right to return. Where a contract contains more than one distinct performance obligation, the transaction price is allocated to each performance obligation based on the standalone selling price of each performance obligation, although these situations do not occur frequently and are generally not included within Ashland’s contracts. Any unsatisfied performance obligations are not material. Standalone selling prices are based on prices Ashland charges to customers, which in some cases is based on established market prices. Ashland generally collects the cash from its customers within 60 days of the product delivery date. Sales and other similar taxes collected from customers on behalf of third parties are excluded from the contract price. All of Ashland’s revenue is derived from contracts with customers, and nearly all contracts with customers contain one performance obligation for the transfer of goods where such performance obligation is satisfied at a point in time. Control of a product is deemed to be transferred to the customer generally upon shipment or delivery. Costs for shipping and handling activities, whether performed before or after the customer obtains control of the goods, are accounted for as fulfillment costs when not reimbursed. Costs incurred to obtain contracts with customers have historically not been significant and are expensed immediately as the amortization period is generally one year or less. Ashland records bad debt expense in specific situations when it is determined that the customer is unable to meet its financial obligation. Trade receivables Trade receivables are defined as receivables arising from contracts with customers and are recorded within the accounts receivable caption within the Condensed Consolidated Balance Sheets. Ashland’s trade receivables were $383 million and $441 million as of December 31, 2020 and September 30, 2020, respectively. Disaggregation of revenue Ashland disaggregates its revenue by segment and geographical region as Ashland believes these categories best depict how management reviews the financial performance of its operations. See the following tables for details (intersegment sales eliminations have been excluded). See Note Q for additional information. Sales by geography Three months ended December 31 (In millions) 2020 2019 Life Sciences North America $ 51 $ 49 Europe 54 49 Asia Pacific 47 42 Latin America & other 18 15 $ 170 $ 155 Three months ended December 31 (In millions) 2020 2019 Personal Care & Household North America $ 41 $ 41 Europe 46 55 Asia Pacific 21 24 Latin America & other 18 17 $ 126 $ 137 Three months ended December 31 (In millions) 2020 2019 Specialty Additives North America $ 45 $ 45 Europe 52 50 Asia Pacific 41 35 Latin America & other 9 9 $ 147 $ 139 Three months ended December 31 (In millions) 2020 2019 Performance Adhesives North America $ 68 $ 64 Europe 10 7 Asia Pacific 4 2 Latin America & other 2 1 $ 84 $ 74 Three months ended December 31 (In millions) 2020 2019 Intermediates and Solvents North America $ 21 $ 15 Europe 4 5 Asia Pacific 7 7 Latin America & other 1 1 $ 33 $ 28

Reportable Segment Information

Reportable Segment Information	3 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Reportable Segment Information	NOTE Q – REPORTABLE SEGMENT INFORMATION Ashland determines its reportable segments based on how operations are managed internally for the products and services sold to customers, including how the results are reviewed by the chief operating decision maker, which includes determining resource allocation methodologies used for reportable segments. Operating income and EBITDA are the primary measures of performance that are reviewed by the chief operating decision maker in assessing each reportable segment's financial performance. Ashland does not aggregate operating segments to arrive at these reportable segments. Reportable Segments Ashland’s reportable segments include Life Sciences, Personal Care & Household, Specialty Additives, Performance Adhesives and Intermediates and Solvents. Unallocated and Other includes corporate governance activities and certain legacy matters. Ashland has also provided subtotals by its consumer and industrial businesses to reflect the end markets served by each reportable segment. Reportable segment business descriptions Consumer Specialties The Consumer Specialties business is comprised of the following reportable segments: Life Sciences is comprised of pharmaceuticals, nutrition, nutraceuticals, agricultural chemicals, advanced materials and fine chemicals. Pharmaceutical solutions include controlled release polymers, disintegrants, film coatings, solubilizers, and tablet binders. Nutrition solutions include thickeners, stabilizers, emulsifiers and additives for enhancing mouthfeel, controlling moisture migration, reducing oil uptake and controlling color. Nutraceutical solutions include products for weight management, joint comfort, stomach and intestinal health, sports nutrition and general wellness, and providing custom formulation, toll processing and particle engineering solutions. Customers include pharmaceutical, food, beverage, nutraceuticals and supplements manufacturers, hospitals and radiologists and industrial manufacturers. Personal Care & Household is comprised of biofunctionals, preservatives, skin care, sun care, oral care, hair care and household. These businesses have a broad range of nature-based, biodegradable, and performance-enhancing ingredients for customer-driven solutions to help protect, renew, moisturize and revitalize skin and hair, and provide solutions for toothpastes, mouth washes and rinses, denture cleaning and care for teeth. Household supplies nature-derived rheology ingredients, biodegradable surface wetting agents, performance encapsulates, and specialty polymers for household, industrial and institutional cleaning products. Customers include formulators at large multinational branded consumer products companies and smaller, independent boutique companies. Industrial Specialties The Industrial Specialties business is comprised of the following reportable segments: Specialty Additives is comprised of rheology- and performance-enhancing additives serving the coatings, construction, energy, automotive and various industrial markets. Solutions include coatings additives for architectural paints, finishes and lacquers, cement- and gypsum- based dry mortars, ready-mixed joint compounds, synthetic plasters for commercial and residential construction, and specialty materials for industrial applications. Products include rheology modifiers (cellulosic and associative thickeners), foam-control agents, surfactants and wetting agents, pH neutralizers, advanced ceramics used in catalytic converters, and environmental filters, ingredients that aid the manufacturing process of ceramic capacitors, plasma display panels and solar cells, ingredients for textile printing, thermoplastic metals and alloys for welding. Products help improve desired functional outcomes through rheology modification and control, water retention, workability, adhesive strength, binding power, film formation, deposition and suspension and emulsification. Customers include global paint manufacturers, electronics and automotive manufacturers, textile mills, the construction industry, and welders. Performance Adhesives is comprised of adhesives used in packaging, converting and structural applications. Packaging adhesives has an extensive line of pressure sensitive adhesives, functional coatings and primers combined with innovative technology solutions for narrow-, mid- and wide-web applications. Products meet stringent requirements in food and beverage safety, shipping, transportation, health and beauty, industrial, postage and security printing. Structural adhesives include light weighting vehicles and eliminating VOCs in buildings. Customers include converters of packaging materials, manufacturers of building materials and tier one suppliers to transportation industry. Other Intermediates and Solvents is comprised of the production of 1,4 butanediol (BDO) and related derivatives, including n-methylpyrrolidone. These products are used as chemical intermediates in the production of engineering polymers and polyurethanes, and as specialty process solvents in a wide array of applications including electronics, pharmaceuticals, water filtration membranes and more. Butanediol is also provided to Life Sciences, Personal Care, and Specialty Additives for use as a raw material. Unallocated and Other generally includes items such as certain significant company-wide restructuring activities, corporate governance costs and legacy costs or activities that relate to divested businesses that are no longer operated by Ashland. Reportable segment results Results of Ashland’s reportable segments are presented based on its management and internal accounting structure. The structure is specific to Ashland; therefore, the financial results of Ashland’s reportable segments are not necessarily comparable with similar information for other comparable companies. Ashland allocates all significant costs to its reportable segments except for certain significant company-wide restructuring activities, certain corporate governance costs and other costs or activities that relate to former businesses that Ashland no longer operates. The service cost component of pension and other postretirement benefits costs is allocated to each reportable segment on a ratable basis; while the remaining components of pension and other postretirement benefits costs are recorded within the other net periodic benefit income caption on the Statements of Consolidated Comprehensive Income (Loss). Ashland refines its expense allocation methodologies to the reportable segments from time to time as internal accounting practices are improved, more refined information becomes available and the industry or market changes. Significant revisions to Ashland’s methodologies are adjusted for all segments on a retrospective basis. This includes charges in the current fiscal year for certain corporate governance costs, which were previously allocated in the first quarter of fiscal 2020. These costs are now reflected in Unallocated and Other for all periods presented. The following table presents various financial information for each reportable segment for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions - unaudited) 2020 2019 SALES Life Sciences $ 170 $ 155 Personal Care & Household 126 137 Consumer Specialties 296 292 Specialty Additives 147 139 Performance Adhesives 84 74 Industrial Specialties 231 213 Intermediates and Solvents 33 28 Intersegment sales (a) Intermediates and Solvents (8 ) — $ 552 $ 533 OPERATING INCOME (LOSS) Life Sciences $ 29 $ 22 Personal Care & Household 15 11 Consumer Specialties 44 33 Specialty Additives (b) 2 9 Performance Adhesives 20 10 Industrial Specialties 22 19 Intermediates and Solvents 2 (12 ) Unallocated and other (27 ) (23 ) $ 41 $ 17 DEPRECIATION EXPENSE Life Sciences $ 9 $ 8 Personal Care & Household 10 10 Consumer Specialties 19 18 Specialty Additives 16 15 Performance Adhesives 3 4 Industrial Specialties 19 19 Intermediates and Solvents 3 3 $ 41 $ 40 AMORTIZATION EXPENSE Life Sciences $ 7 $ 7 Personal Care & Household 9 9 Consumer Specialties 16 16 Specialty Additives 5 5 Performance Adhesives — — Industrial Specialties 5 5 Intermediates and Solvents — — $ 21 $ 21 EBITDA (c) Life Sciences $ 45 $ 37 Personal Care & Household 34 30 Consumer Specialties 79 67 Specialty Additives 23 29 Performance Adhesives 23 14 Industrial Specialties 46 43 Intermediates and Solvents 5 (9 ) Unallocated and other (27 ) (23 ) $ 103 $ 78 December 31 September 30 (In millions - unaudited) 2020 2020 TOTAL ASSETS Life Sciences $ 1,987 $ 1,974 Personal Care & Household 904 939 Consumer Specialties 2,891 2,913 Specialty Additives 1,662 1,666 Performance Adhesives 594 591 Industrial Specialties 2,256 2,257 Intermediates and Solvents 158 161 Unallocated and other 1,437 1,546 $ 6,742 $ 6,877 (a) Intersegment sales from Intermediates and Solvents are accounted for at prices that approximate fair value. All other intersegment sales are accounted for at cost. (b) Includes a capital project impairment of $9 million for the three months ended December 31, 2020 relating to a long-term capital project plan change at a plant facility. ( c ) Excludes income (loss) from discontinued operations, other net periodic benefit income (expense) and net income (loss) on divestitures. See the Statement of Consolidated Comprehensive Income (Loss) for applicable amounts excluded.

Subsequent Events

Subsequent Events	3 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	NOTE R – SUBSEQUENT EVENTS On January 19, 2021 Ashland announced it had signed a definitive agreement to acquire the personal care business from Schülke & Mayr GmbH, a portfolio company of the global investment organization EQT. Under the terms of the agreement, Ashland will pay €262.5 million in an all cash transaction, which is expected to be completed before the end of the June 30, 2021 quarter subject to customary closing conditions and required regulatory approvals.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation	Basis of presentation The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial reporting and Securities and Exchange Commission (SEC) regulations. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. These statements omit certain information and footnote disclosures required for complete annual financial statements and, therefore, should be read in conjunction with Ashland Global Holdings Inc. and consolidated subsidiaries (Ashland) Annual Report on Form 10-K for the fiscal year ended September 30, 2020. Results of operations for the period ended December 31, 2020 are not necessarily indicative of the expected results for the remaining quarters in the fiscal year. All amounts are presented in millions except per-share amounts. Ashland’s reportable segments include the consumer specialty businesses: Life Sciences and Personal Care & Household; the industrial specialty businesses: Specialty Additives and Performance Adhesives; and Intermediates and Solvents. Unallocated and Other includes corporate governance activities and certain legacy matters. For additional information, see Note Q.
Use of Estimates, Risks and Uncertainties	Use of estimates, risks and uncertainties The preparation of Ashland’s Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and the disclosures of contingent assets and liabilities. Significant items that are subject to such estimates and assumptions include, but are not limited to, long-lived assets (including goodwill and other intangible assets), income taxes and liabilities and receivables associated with asbestos litigation and environmental remediation. Although management bases its estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances, actual results could differ significantly from the estimates under different assumptions or conditions. Ashland’s results are affected by domestic and international economic, political, legislative, regulatory and legal actions. Economic conditions, such as recessionary trends, inflation, interest and monetary exchange rates, government fiscal policies and changes in the prices of certain key raw materials, can have a significant effect on operations. While Ashland maintains reserves for anticipated liabilities and carries various levels of insurance, Ashland could be affected by civil, criminal, regulatory or administrative actions, claims or proceedings relating to asbestos, environmental remediation or other matters.
New Accounting Pronouncements	New accounting pronouncements A description of new U.S. GAAP accounting standards issued or adopted during the current year is required in interim financial reporting. A detailed listing of new accounting standards relevant to Ashland is included in the Annual Report on Form 10-K for the fiscal year ended September 30, 2020. The following standards relevant to Ashland were either issued or adopted in the current fiscal year or will become effective in a subsequent period. In June 2016, the FASB issued amended accounting guidance related to the measurement of credit losses on financial instruments. The amended accounting guidance changes the impairment model for most financial assets to require measurement and recognition of expected credit losses for financial assets held. This guidance became effective for Ashland on October 1, 2020. As a result, Ashland recorded a $3 million increase in its allowance for credit losses, primarily related to asbestos receivables, and a $2 million decrease to retained earnings, net of tax, reflecting the cumulative effect on retained earnings. Under the new expected credit loss model, Ashland records an allowance for credit losses inherent in its receivables from revenue transactions and reinsurance recoverables. The allowance for credit losses is a valuation account deducted from the amortized cost basis of the assets to present their net carrying value at the amount expected to be collected. Ashland estimates expected credit losses based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. When measuring expected credit losses, Ashland pools assets with similar country risk and credit risk characteristics. Each period the allowance for credit losses is adjusted through earnings to reflect expected credit losses over the remaining lives of the assets. For the three months ending December 31, 2020, no significant credit losses were incurred within the Statements of Consolidated Comprehensive Income (Loss).
Fair Value of Financial Instruments Policy	As required by U.S. GAAP, Ashland uses applicable guidance for defining fair value, the initial recording and periodic remeasurement of certain assets and liabilities measured at fair value and related disclosures for instruments measured at fair value. Fair value accounting guidance establishes a fair value hierarchy, which prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). An instrument’s categorization within the fair value hierarchy is based upon the lowest level of input that is significant to the instrument’s fair value measurement. The three levels within the fair value hierarchy are described as follows. Level 1 – Observable inputs such as unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 – Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. Level 3 – Unobservable inputs for the asset or liability for which there is little, if any, market activity at the measurement date. Unobservable inputs reflect Ashland’s own assumptions about what market participants would use to price the asset or liability. The inputs are developed based on the best information available in the circumstances, which might include Ashland’s own financial data such as internally developed pricing models, discounted cash flow methodologies, as well as instruments for which the fair value determination requires significant management judgment. For assets that are measured using quoted prices in active markets (Level 1), the total fair value is the published market price per unit multiplied by the number of units held without consideration of transaction costs. Assets and liabilities that are measured using significant other observable inputs (Level 2) are primarily valued by reference to quoted prices of similar assets or liabilities in active markets, adjusted for any terms specific to that asset or liability. For all other assets and liabilities for which unobservable inputs are used (Level 3), fair value is derived using fair value models, such as a discounted cash flow model or other standard pricing models that Ashland deems reasonable.
Inventories	Inventories are carried at the lower of cost or net realizable value. Inventories are primarily stated at cost using the weighted-average cost method. In addition, certain inventories are valued at cost using the last-in, first-out (LIFO) method.
Goodwill and Intangible Assets, Goodwill	Ashland tests goodwill and other indefinite-lived intangible assets for impairment annually as of July 1 and when events and circumstances indicate an impairment may have occurred. Ashland tests goodwill and other indefinite-lived intangible assets for impairment by comparing the estimated fair value of the reporting units (for goodwill) and other indefinite-lived intangible assets to the related carrying value. If the carrying amount of a reporting unit or other indefinite-lived intangible asset exceeds its estimated fair value, Ashland records an impairment loss based on the difference between fair value and carrying amount, in the case of reporting units, not to exceed to the associated carrying amount of goodwill. Ashland’s assessment of an impairment on any of these assets classified currently as having indefinite lives, including goodwill, could change in future periods if significant events happen and/or circumstances change that effect the previously mentioned assumptions such as: a significant change in projected business results, a divestiture decision, increase in Ashland’s weighted-average cost of capital rates, decrease in growth rates or assumptions, economic deterioration that is more severe or of a longer duration than anticipated, or another significant economic event. Ashland’s reporting units align with its reportable segments. Ashland determined that its reporting units are Life Sciences, Personal Care & Household, Specialty Additives, Performance Adhesives, and Intermediates and Solvents. N o indicators of impairment were identified in the first quarter of Fiscal 2021.
Finite-Lived Intangible Asset	Intangible assets principally consist of trademarks and trade names, intellectual property and customer and supplier relationships. Intangible assets classified as finite are amortized on a straight-line basis over their estimated useful lives. The cost of trademarks and trade names is amortized principally over 3 to 25 years, intellectual property over 5 to 25 years, and customer and supplier relationships over 3 to 24 years.
Goodwill and Intangible Assets, Intangible Assets, Indefinite-Lived	Ashland annually reviews, as of July 1, indefinite-lived intangible assets for possible impairment or whenever events or changes in circumstances indicate that carrying amounts may not be recoverable. Trademarks and trade names are valued using a “relief-from-royalty” valuation method compared to the carrying value. No indicators of impairment were identified in the first quarter of Fiscal 2021.
Commitments and Contingencies Policy	Ashland is subject to liabilities from claims alleging personal injury caused by exposure to asbestos. Such claims result from indemnification obligations undertaken in 1990 in connection with the sale of Riley Stoker Corporation (Riley) and the acquisition of Hercules in November 2008. Although Riley, a former subsidiary, was neither a producer nor a manufacturer of asbestos, its industrial boilers contained some asbestos-containing components provided by other companies. Hercules, an indirect wholly-owned subsidiary of Ashland, has liabilities from claims alleging personal injury caused by exposure to asbestos. Such claims typically arise from alleged exposure to asbestos fibers from resin encapsulated pipe and tank products sold by one of Hercules’ former subsidiaries to a limited industrial market. To assist in developing and annually updating independent reserve estimates for future asbestos claims and related costs given various assumptions for Ashland and Hercules asbestos claims, Ashland retained Nathan Associates Inc. (Nathan). The methodology used by Nathan to project future asbestos costs is based largely on recent experience, including claim-filing and settlement rates, disease mix, enacted legislation, open claims and litigation defense. The claim experience of Ashland and Hercules are separately compared to the results of previously conducted third party epidemiological studies estimating the number of people likely to develop asbestos-related diseases. Those studies were undertaken in connection with national analyses of the population expected to have been exposed to asbestos. Using that information, Nathan estimates a range of the number of future claims that may be filed, as well as the related costs that may be incurred in resolving those claims. Changes in asbestos-related liabilities and receivables are recorded on an after-tax basis within the discontinued operations caption in the Statements of Consolidated Comprehensive Income (Loss).
Environmental Cost Policy	The total reserves for environmental remediation reflect Ashland’s estimates of the most likely costs that will be incurred over an extended period to remediate identified conditions for which the costs are reasonably estimable, without regard to any third-party recoveries. Engineering studies, probability techniques, historical experience and other factors are used to identify and evaluate remediation alternatives and their related costs in determining the estimated reserves for environmental remediation. Ashland continues to discount certain environmental sites and regularly adjusts its reserves as environmental remediation continues. Ashland has estimated the value of its probable insurance recoveries associated with its environmental reserve based on management’s interpretations and estimates surrounding the available or applicable insurance coverage. At December 31, 2020 and September 30, 2020 , Ashland’s recorded receivable for these probable insurance recoveries was $ million, of which $ 12 million at December 31, 2020 and September 30, 2020 was classified in other noncurrent assets on the Condensed Consolidated Balance Sheets.
Earnings Per Share	The following is the computation of basic and diluted earnings per share (EPS) from continuing operations attributable to Ashland. Stock appreciation rights (SARs), stock options and warrants available to purchase shares outstanding for each reporting period whose grant price was greater than the average market price of Ashland Common Stock for each applicable period were not included in the computation of income from continuing operations per diluted share because the effect of these instruments would be antidilutive. The total number of these shares outstanding was approximately
Segment Reporting	Ashland determines its reportable segments based on how operations are managed internally for the products and services sold to customers, including how the results are reviewed by the chief operating decision maker, which includes determining resource allocation methodologies used for reportable segments. Operating income and EBITDA are the primary measures of performance that are reviewed by the chief operating decision maker in assessing each reportable segment's financial performance. Ashland does not aggregate operating segments to arrive at these reportable segments.

Discontinued Operations (Tables

Discontinued Operations (Tables)	3 Months Ended
	Dec. 31, 2020
Components of Amounts in the Statements of Consolidated Income (Loss) Related To Discontinued Operations	Components of amounts reflected in the Statements of Consolidated Comprehensive Income (Loss) related to discontinued operations are presented in the following table for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Income (loss) from discontinued operations (net of tax) Composites/Marl facility $ — $ — Valvoline — (1 ) Water Technologies — (1 ) Distribution (1 ) — Gain (loss) on disposal of discontinued operations (net of taxes) Composites/Marl facility (4 ) — $ (5 ) $ (2 )
Composites/Marl facility [Member]
Components of Amounts in the Statements of Consolidated Income (Loss) Related To Discontinued Operations	The following table presents a reconciliation of the captions within Ashland's Statements of Consolidated Comprehensive Income (Loss) for the income (loss) from discontinued operations attributable to Composites and the Marl facility for the three months ended December 31, 2019. The Maleic business, which was sold during fiscal 2020 to AOC, was operated under the Composites business and Marl facility disposal group and is therefore reported in discontinued operations. Three months ended December 31 (In millions) 2019 Income (loss) from discontinued operations attributable to Composites/Marl facility Sales $ 12 Cost of sales (10 ) Selling, general and administrative expense (2 ) Equity and other income 2 Pretax income of discontinued operations 2 Income tax expense (2 ) Income from discontinued operations $ —

Restructuring Activities (Table

Restructuring Activities (Tables)	3 Months Ended
	Dec. 31, 2020
Restructuring And Related Activities [Abstract]
Summary of Amount of Restructuring Reserves Related to Program	The following table details at December 31, 2020 and 2019, the amount of restructuring severance reserves related to this program. The severance reserves were primarily recorded within accrued expenses and other liabilities in the Condensed Consolidated Balance Sheet as of December 31, 2020 and December 31, 2019. (In millions) Severance costs Balance at of September 30, 2020 39 Restructuring reserve 8 Utilization (cash paid) (11 ) Balance at December 31, 2020 $ 36 (In millions) Severance costs Balance at of September 30, 2019 — Restructuring reserve 3 Utilization (cash paid) — Balance at December 31, 2019 $ 3 The following table details at December 31, 2019, the amount of restructuring reserves related to the programs discussed above, and the related activity in these reserves during the three months ended December 31, 2019. The severance reserve was primarily recorded within accrued expenses and other liabilities in the Condensed Consolidated Balance Sheet as of December 31, 2019. (In millions) Severance costs Balance at of September 30, 2019 7 Restructuring reserve 1 Utilization (cash paid) (3 ) Balance at December 31, 2019 $ 5

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Summary of Financial Instruments Subject to Recurring Fair Value Measurements	The following table summarizes financial instruments subject to recurring fair value measurements as of December 31, 2020. Carrying Total fair Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs (In millions) value value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 335 $ 335 $ 335 $ — $ — Restricted investments (a) 346 346 346 — — Investment of captive insurance company (b) 8 8 8 — — Total assets at fair value $ 689 $ 689 $ 689 $ — $ — Liabilities Foreign currency derivatives $ 1 $ 1 $ — $ 1 $ — (a) Included in restricted investments is $30 million classified in the other current assets caption on the Condensed Consolidated Balance Sheets. (b) Included in other noncurrent assets in the Condensed Consolidated Balance Sheets. The following table summarizes financial asset instruments subject to recurring fair value measurements as of September 30, 2020. Carrying Total fair Quoted prices in active markets for identical assets Significant other observable inputs Significant unobservable inputs (In millions) value value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 454 $ 454 $ 454 $ — $ — Restricted investments (a) 331 331 331 — — Investment of captive insurance company (b) 9 9 9 — — Foreign currency derivatives 1 1 — 1 — Total assets at fair value $ 795 $ 795 $ 794 $ 1 $ — Liabilities Foreign currency derivatives $ 3 $ 3 $ — $ 3 $ — (a) Included in restricted investments is $30 million classified in the other current assets caption on the Condensed Consolidated Balance Sheets. (b) Included in other noncurrent assets in the Condensed Consolidated Balance Sheets.
Summary of Investment Portfolio	The following table provides a summary of the activity within the investment portfolio as of December 31, 2020 and September 30, 2020: (In millions) December 31 2020 September 30 2020 Original cost $ 335 $ 335 Accumulated adjustments, net (a) (50 ) (30 ) Adjusted cost, beginning of year 285 305 Investment income (b) 5 10 Net unrealized gain (c) 52 46 Realized gains (c) 11 2 Settlement funds 1 3 Disbursements (8 ) (35 ) Fair value $ 346 $ 331 (a) The accumulated adjustments include investment income, realized gains, disbursements and settlements recorded in previous periods. (b) Investment income for the demand deposit includes interest income as well as dividend income transferred from the equity and fixed income mutual funds. (c) Presented under the original cost method. The following table presents gross unrealized gains and losses for the restricted investment securities as of December 31, 2020 and September 30, 2020: Gross Gross (In millions) Adjusted Cost Unrealized Gain Unrealized Loss Fair Value As of December 31, 2020 Demand deposit $ 9 $ — $ — $ 9 Equity mutual fund 101 38 — 139 Fixed income mutual fund 184 14 — 198 $ 294 $ 52 $ — $ 346 As of September 30, 2020 Demand deposit $ 7 $ — $ — $ 7 Equity mutual fund 116 31 (1 ) 146 Fixed income mutual fund 162 16 — 178 $ 285 $ 47 $ (1 ) $ 331
Summary of Investment Income, Net Gains and Losses Realized and Disbursements Related to Investments	The following table presents the investment income, net gains and losses realized and disbursements related to the investments within the portfolio for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Investment income $ 5 $ 4 Net gains (losses) unrealized (a) 18 9 Disbursements (8 ) (10 ) (a) Ashland determined that all unrealized gains and (losses) were related to equity securities with readily determinable fair values. Due to the new accounting guidance adopted in the first quarter of fiscal year 2019, the net unrealized gains and (losses) during the year ended September 30, 2019 and forward were recorded within the net interest and other expense caption in the Statements of Consolidated Income (Loss).
Summary of Net Gains and Losses on Foreign Currency Derivatives	The following table summarizes the net gains and losses recognized during the three months ended December 31, 2020 and 2019 within the Statements of Consolidated Comprehensive Income (Loss). Three months ended December 31 (In millions) 2020 2019 Foreign currency derivative gains (losses) $ 3 $ 1
Summary of Fair Values of Outstanding Foreign Currency Derivatives	The following table summarizes the fair values of the outstanding foreign currency derivatives as of December 31, 2020 and September 30, 2020 included in accounts receivable and accrued expenses and other liabilities of the Condensed Consolidated Balance Sheets. December 31 September 30 (In millions) 2020 2020 Foreign currency derivative assets $ — $ 1 Notional contract values 168 170 Foreign currency derivative liabilities $ 1 $ 3 Notional contract values 221 215

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Summary of Inventories	The following table summarizes Ashland’s inventories as of the reported Condensed Consolidated Balance Sheet dates. (In millions) December 31, 2020 September 30, 2020 Finished products $ 341 $ 336 Raw materials, supplies and work in process 196 193 $ 537 $ 529

Goodwill and Other Intangibles

Goodwill and Other Intangibles (Tables)	3 Months Ended
	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Summary of Goodwill by Reportable Segment	The following is a progression of goodwill by reportable segment for the three months ended December 31, 2020. (In millions) Life Sciences Personal Care & Household (a) Specialty Additives (a) Performance Adhesives Intermediates and Solvents (a) Total Balance at September 30, 2020 $ 861 $ — $ 444 $ 453 $ — $ 1,758 Currency translation 21 — 13 — — 34 Balance at December 31, 2020 $ 882 $ — $ 457 $ 453 $ — $ 1,792 (a) As of December 31, 2020 a nd September 30, 2020 , t here w ere accumulated impairment s of $ 356 million, $ 174 million and $ 90 million related to the Personal Care & Household, Specialty Additives and Intermediates and Solvents reportable segment s, respectively .
Summary of Intangible Assets	Intangible assets were comprised of the following as of December 31, 2020 and September 30, 2020. December 31, 2020 Gross Net carrying Accumulated carrying (In millions) amount amortization amount Definite-lived intangibles Trademarks and trade names $ 66 $ (33 ) $ 33 Intellectual property 731 (460 ) 271 Customer and supplier relationships 770 (351 ) 419 Total definite-lived intangibles 1,567 (844 ) 723 Indefinite-lived intangibles Trademarks and trade names 278 — 278 Total intangible assets $ 1,845 $ (844 ) $ 1,001 September 30, 2020 Gross Net carrying Accumulated carrying (In millions) amount amortization amount Definite-lived intangibles Trademarks and trade names $ 66 $ (32 ) $ 34 Intellectual property 721 (442 ) 279 Customer and supplier relationships 757 (335 ) 422 Total definite-lived intangibles 1,544 (809 ) 735 Indefinite-lived intangibles Trademarks and trade names 278 — 278 Total intangible assets $ 1,822 $ (809 ) $ 1,013

Debt (Tables)

Debt (Tables)	3 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Summary of Current and Long-term Debt	The following table summarizes Ashland’s current and long-term debt as of the dates reported in the Condensed Consolidated Balance Sheets. (In millions) December 31, 2020 September 30, 2020 4.750% notes, due 2022 $ 411 $ 411 2.00% Senior Notes, due 2028 (Euro 500 million principal) 614 587 6.875% notes, due 2043 282 282 Term loan A 250 250 Accounts receivable securitizations 69 177 6.50% junior subordinated notes, due 2029 55 55 Revolving credit facility — 80 Other (a) 13 11 Total debt 1,694 1,853 Short-term debt (includes current portion of long-term debt) (93 ) (280 ) Long-term debt (less current portion) $ 1,601 $ 1,573 (a) Includes $15 million of debt issuance cost discounts as of both December 31, 2020 and September 30, 2020. Additionally, as of December 31, 2020 and September 30, 2020, Other includes a European short-term loan facility with an outstanding balance of $24 million and $23 million, respectively.

Leasing Arrangements (Tables)

Leasing Arrangements (Tables)	3 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Components of Lease Cost Recognized	The components of lease cost recognized within our Statements of Consolidated Comprehensive Income (Loss) were as follows: Three months ended December 31 (In millions) Location 2020 2019 Lease cost: Operating lease cost Selling, General & Administrative $ 3 $ 5 Operating lease cost Cost of Sales 4 4 Variable lease cost Cost of Sales 1 1 Short-term leases Cost of Sales 1 — Total lease cost $ 9 $ 10
Summary of Lease Assets and Liabilities	The following table summarizes Ashland’s lease assets and liabilities as presented in the Condensed Consolidated Balance Sheet: (In millions) December 31, 2020 September 30, 2020 Assets Operating lease assets, net $ 137 $ 137 Total lease assets 137 137 Liabilities Current operating lease obligations $ 23 $ 23 Non-current operating lease obligations 124 124 Total lease liabilities $ 147 $ 147
Schedule of Cash Paid for Amounts Included in the Measurement of Operating Lease Liabilities	Cash paid for amounts included in the measurement of operating lease liabilities: Three months ended December 31 (In millions) 2020 2019 Operating cash flows from operating leases $ 7 $ 9
Schedule of Maturities Analysis of Lease Liabilities	Maturities of lease liabilities are shown below as of December 31, 2020 and September 30, 2020: (In millions) December 31, 2020 September 30, 2020 Remainder of 2021 $ 20 $ 28 2022 37 35 2023 17 17 2024 14 13 2025 12 11 Thereafter $ 90 $ 88 Total lease payments 190 192 Less amount of lease payment representing interest (43 ) (45 ) Total present value of lease payments $ 147 $ 147

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Summary of Changes in Unrecognized Tax Benefits	Changes in unrecognized tax benefits are summarized as follows for the three months ended December 31, 2020. (In millions) Balance at October 1, 2020 $ 171 Increases related to positions taken in the current year 7 Balance at December 31, 2020 $ 178

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	3 Months Ended
	Dec. 31, 2020
Compensation And Retirement Disclosure [Abstract]
Schedule of Components of Pension and Other Postretirement Benefit Costs for Continuing Operation	The following table details the components of pension and other postretirement benefit costs for continuing operations. Pension benefits Other postretirement benefits (In millions) 2020 2019 2020 2019 Three months ended December 31 Service cost $ 1 $ 1 $ — $ — Interest cost 2 2 — 1 Expected return on plan assets (2 ) (3 ) — — Curtailment — — — — Total net periodic benefit costs $ 1 $ — $ — $ 1

Litigation, Claims and Contin_2

Litigation, Claims and Contingencies (Tables)	3 Months Ended
	Dec. 31, 2020
Loss Contingencies [Line Items]
Reconciliation of Changes in Environmental Contingencies and Asset Retirement Obligations Reserve	The following table provides a reconciliation of the changes in the environmental remediation reserves during the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Reserve - beginning of period $ 200 $ 186 Disbursements (10 ) (9 ) Revised obligation estimates and accretion 5 2 Reserve - end of period $ 195 $ 179
Components of Environmental Remediation Expense	Components of environmental remediation expense included within the selling, general and administrative expense caption of the Statements of Consolidated Comprehensive Income (Loss) are presented in the following table for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions) 2020 2019 Environmental expense $ 5 $ 2 Accretion — — Legal expense 1 2 Total expense 6 4 Insurance receivable (1 ) — Total expense, net of receivable activity (a) $ 5 $ 4 (a) Net expense of $1 million for the three months ended December 31, 2020, relates to divested businesses which qualified for treatment as discontinued operations for which certain environmental liabilities were retained by Ashland. These amounts are classified within the income from discontinued operations caption of the Statements of Consolidated Comprehensive Income (loss).
Ashland [Member]
Loss Contingencies [Line Items]
Summary of Asbestos Claims Activity	A summary of Ashland asbestos claims activity, excluding Hercules claims, follows. Three months ended December 31 Years ended September 30 (In thousands) 2020 2019 2020 2019 2018 Open claims - beginning of year 49 53 53 53 54 New claims filed 1 — 2 2 2 Claims settled — — (1 ) (1 ) (1 ) Claims dismissed (1 ) (2 ) (5 ) (1 ) (2 ) Open claims - end of period 49 51 49 53 53
Progression of Activity in Asbestos Reserve Accounts	A progression of activity in the asbestos reserve is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Asbestos reserve - beginning of year $ 335 $ 352 $ 352 $ 380 $ 419 Reserve adjustment — — 13 1 (8 ) Amounts paid (10 ) (10 ) (30 ) (29 ) (31 ) Asbestos reserve - end of period (a) $ 325 $ 342 $ 335 $ 352 $ 380 (a) Included $ million classified in accrued expenses and other liabilities on the Condensed Consolidated Balance Sheets as of both December 31, 2020 and September 30, 2020 .
Progression of Insurance Receivable	A progression of activity in the Ashland insurance receivable is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Insurance receivable - beginning of year $ 103 $ 123 $ 123 $ 140 $ 155 Receivable adjustment (a) (2 ) — 1 (5 ) (5 ) Insurance settlement — — (10 ) — — Amounts collected (3 ) (1 ) (11 ) (12 ) (10 ) Insurance receivable - end of period (b) $ 98 $ 122 $ 103 $ 123 $ 140 (a) The three months ended December 31, 2020 includes a $2 million adjustment related to allowances for credit losses as a result of Ashland’s adoption of the new credit measurement standard described in Note A. ( b ) Included
Hercules [Member]
Loss Contingencies [Line Items]
Summary of Asbestos Claims Activity	A summary of Hercules’ asbestos claims activity follows. Three months ended December 31 Years ended September 30 (In thousands) 2020 2019 2020 2019 2018 Open claims - beginning of year 12 13 13 13 12 New claims filed 1 — 1 1 2 Claims dismissed (1 ) — (2 ) (1 ) (1 ) Open claims - end of period 12 13 12 13 13
Progression of Activity in Asbestos Reserve Accounts	A progression of activity in the asbestos reserve is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Asbestos reserve - beginning of year $ 229 $ 252 $ 252 $ 282 $ 323 Reserve adjustments — — (3 ) (10 ) (19 ) Amounts paid (5 ) (5 ) (20 ) (20 ) (22 ) Asbestos reserve - end of period (a) $ 224 $ 247 $ 229 $ 252 $ 282 (a) Included
Progression of Insurance Receivable	A progression of activity in the Hercules insurance receivable is presented in the following table. Three months ended December 31 Years ended September 30 (In millions) 2020 2019 2020 2019 2018 Insurance receivable - beginning of year $ 47 $ 49 $ 49 $ 54 $ 68 Receivable adjustment (a) (1 ) — (2 ) (5 ) (14 ) Insurance receivable - end of period $ 46 $ 49 $ 47 $ 49 $ 54 (a) The three months ended December 31, 2020 includes a $1 million adjustment related to allowances for credit losses as a result of Ashland’s adoption of the new credit measurement standard described in Note A

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings per Share	The following is the computation of basic and diluted earnings per share (EPS) from continuing operations attributable to Ashland. Stock appreciation rights (SARs), stock options and warrants available to purchase shares outstanding for each reporting period whose grant price was greater than the average market price of Ashland Common Stock for each applicable period were not included in the computation of income from continuing operations per diluted share because the effect of these instruments would be antidilutive. The total number of these shares outstanding was approximately Three months ended December 31 (In millions, except per share data) 2020 2019 Numerator Numerator for basic and diluted EPS - Income (loss) from continuing operations $ 61 $ 34 Denominator Denominator for basic EPS - Weighted- average common shares outstanding 60 60 Share based awards convertible to common shares 1 1 Denominator for diluted EPS - Adjusted weighted- average shares and assumed conversions 61 61 EPS from continuing operations Basic $ 1.00 $ 0.57 Diluted 0.99 0.56

Equity Items (Tables)

Equity Items (Tables)	3 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Components of Accumulated Other Comprehensive Income (Loss)	Components of other comprehensive income (loss) recorded in the Statements of Consolidated Comprehensive Income (Loss) are presented below, before tax and net of tax effects. 2020 2019 (In millions) Before tax Tax (expense) benefit Net of tax Before tax Tax (expense) benefit Net of tax Three months ended December 31 Other comprehensive income (loss) Unrealized translation gain $ 48 $ — $ 48 $ 38 $ — $ 38 Total other comprehensive income $ 48 $ — $ 48 $ 38 $ — $ 38
Summary of Reconciliation of Changes in Stockholders' Equity	Summary of stockholders’ equity A reconciliation of changes in stockholders’ equity are as follows: Three months ended December 31 (In millions) 2020 2019 Common stock and paid in capital Balance, beginning of period $ 770 $ 757 Common shares issued under stock incentive and other plans (a) 1 1 Balance, end of period 771 758 Retained earnings Balance, beginning of period 2,649 3,224 Adoption of new accounting pronouncements (2 ) — Net income 56 32 Regular dividends (17 ) (17 ) Balance, end of period 2,686 3,239 Accumulated other comprehensive income (loss) Balance, beginning of period (383 ) (410 ) Unrealized translation gain 48 38 Balance, end of period (335 ) (372 ) Total stockholders' equity $ 3,122 $ 3,625 Cash dividends declared per common share $ 0.275 $ 0.275 (a) Common shares issued were 99,194 shares and 70,461 shares for the three months ended December 31, 2020 and 2019, respectively.

Stock Incentive Plans (Tables)

Stock Incentive Plans (Tables)	3 Months Ended
	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Components of Pretax Stock-Based Compensation Expense Included in Continuing Operations	The components of Ashland’s pre-tax stock-based compensation expense included in continuing operations are as follows: Three months ended December 31 (In millions) 2020 (a) 2019 (b) SARs $ 1 $ 2 Nonvested stock awards 2 2 Performance share awards 2 1 $ 5 $ 5 (a) Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2020. (b) Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2019.

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Disaggregation of Revenue	Ashland disaggregates its revenue by segment and geographical region as Ashland believes these categories best depict how management reviews the financial performance of its operations. See the following tables for details (intersegment sales eliminations have been excluded). See Note Q for additional information. Sales by geography Three months ended December 31 (In millions) 2020 2019 Life Sciences North America $ 51 $ 49 Europe 54 49 Asia Pacific 47 42 Latin America & other 18 15 $ 170 $ 155 Three months ended December 31 (In millions) 2020 2019 Personal Care & Household North America $ 41 $ 41 Europe 46 55 Asia Pacific 21 24 Latin America & other 18 17 $ 126 $ 137 Three months ended December 31 (In millions) 2020 2019 Specialty Additives North America $ 45 $ 45 Europe 52 50 Asia Pacific 41 35 Latin America & other 9 9 $ 147 $ 139 Three months ended December 31 (In millions) 2020 2019 Performance Adhesives North America $ 68 $ 64 Europe 10 7 Asia Pacific 4 2 Latin America & other 2 1 $ 84 $ 74 Three months ended December 31 (In millions) 2020 2019 Intermediates and Solvents North America $ 21 $ 15 Europe 4 5 Asia Pacific 7 7 Latin America & other 1 1 $ 33 $ 28

Reportable Segment Information

Reportable Segment Information (Tables)	3 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Summary of Financial Information for Each Reportable Segment	The following table presents various financial information for each reportable segment for the three months ended December 31, 2020 and 2019. Three months ended December 31 (In millions - unaudited) 2020 2019 SALES Life Sciences $ 170 $ 155 Personal Care & Household 126 137 Consumer Specialties 296 292 Specialty Additives 147 139 Performance Adhesives 84 74 Industrial Specialties 231 213 Intermediates and Solvents 33 28 Intersegment sales (a) Intermediates and Solvents (8 ) — $ 552 $ 533 OPERATING INCOME (LOSS) Life Sciences $ 29 $ 22 Personal Care & Household 15 11 Consumer Specialties 44 33 Specialty Additives (b) 2 9 Performance Adhesives 20 10 Industrial Specialties 22 19 Intermediates and Solvents 2 (12 ) Unallocated and other (27 ) (23 ) $ 41 $ 17 DEPRECIATION EXPENSE Life Sciences $ 9 $ 8 Personal Care & Household 10 10 Consumer Specialties 19 18 Specialty Additives 16 15 Performance Adhesives 3 4 Industrial Specialties 19 19 Intermediates and Solvents 3 3 $ 41 $ 40 AMORTIZATION EXPENSE Life Sciences $ 7 $ 7 Personal Care & Household 9 9 Consumer Specialties 16 16 Specialty Additives 5 5 Performance Adhesives — — Industrial Specialties 5 5 Intermediates and Solvents — — $ 21 $ 21 EBITDA (c) Life Sciences $ 45 $ 37 Personal Care & Household 34 30 Consumer Specialties 79 67 Specialty Additives 23 29 Performance Adhesives 23 14 Industrial Specialties 46 43 Intermediates and Solvents 5 (9 ) Unallocated and other (27 ) (23 ) $ 103 $ 78 December 31 September 30 (In millions - unaudited) 2020 2020 TOTAL ASSETS Life Sciences $ 1,987 $ 1,974 Personal Care & Household 904 939 Consumer Specialties 2,891 2,913 Specialty Additives 1,662 1,666 Performance Adhesives 594 591 Industrial Specialties 2,256 2,257 Intermediates and Solvents 158 161 Unallocated and other 1,437 1,546 $ 6,742 $ 6,877 (a) Intersegment sales from Intermediates and Solvents are accounted for at prices that approximate fair value. All other intersegment sales are accounted for at cost. (b) Includes a capital project impairment of $9 million for the three months ended December 31, 2020 relating to a long-term capital project plan change at a plant facility. ( c ) Excludes income (loss) from discontinued operations, other net periodic benefit income (expense) and net income (loss) on divestitures. See the Statement of Consolidated Comprehensive Income (Loss) for applicable amounts excluded.

Significant Accounting Polici_3

Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Sep. 30, 2020
Significant Accounting Policies [Line Items]
Increase in allowance in credit losses	$ 3
Net decrease to retained earnings	(3,122)	$ (3,036)
Retained earnings [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU- 2016-13 [Member]
Significant Accounting Policies [Line Items]
Net decrease to retained earnings	$ 2

Divestitures - Additional Infor

Divestitures - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from sale of business	$ 98
Net income on divestitures		$ 14	$ 3
Composites Segment and the Intermediates and Solvents Marl Facility [Member] | INEOS Enterprises [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Transition service fee income recognized		3	$ 3
Specialty Ingredients Facility [Member] | Specialty Additives [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from sale of business		14
Net income on divestitures		14
Proceeds from sale of businesses including deposits received in fiscal year 2020.		$ 20

Discontinued Operations - Compo

Discontinued Operations - Components of Consolidated Comprehensive Income (Loss) Related to Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations (net of tax)	$ (5)	$ (2)
Composites/Marl facility [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposal of discontinued operations (net of taxes)	(4)
Valvoline [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations (net of tax)		(1)
Water Technologies [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations (net of tax)		$ (1)
Distribution [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations (net of tax)	$ (1)

Discontinued Operations - Recon

Discontinued Operations - Reconciliation of Consolidated Income (Loss) From Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income (loss) from discontinued operations attributable to Composites/Marl facility
Income from discontinued operations	$ (5)	$ (2)
Composites/Marl facility [Member]
Income (loss) from discontinued operations attributable to Composites/Marl facility
Sales		12
Cost of sales		(10)
Selling, general and administrative expense		(2)
Equity and other income		2
Pretax income of discontinued operations		2
Income tax expense		$ (2)

Restructuring Activities - Addi

Restructuring Activities - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Selling General and Administrative Expenses {Member] | Voluntary Severance Offer [Member]
Restructuring Cost And Reserve [Line Items]
Severance expense		$ 1
Fiscal 2020 and 2021 Restructuring Severance Costs [Member]
Restructuring Cost And Reserve [Line Items]
Severance expense	$ 8	3
Restructuring reserve	36	3	$ 39	$ 0
Severance Costs [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring reserve	$ 0	$ 5		$ 7

Restructuring Activities - Summ

Restructuring Activities - Summary of Severance Reserves and Facility Cost Reserves (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fiscal 2020 and 2021 Restructuring Severance Costs [Member]
Restructuring Cost And Reserve [Line Items]
Beginning balance	$ 39	$ 0
Restructuring reserve	8	3
Utilization (cash paid)	(11)	0
Ending balance	36	3
Severance Costs [Member]
Restructuring Cost And Reserve [Line Items]
Beginning balance		7
Restructuring reserve		1
Utilization (cash paid)		(3)
Ending balance	$ 0	$ 5

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Instruments Subject to Recurring Fair Value Measurements (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Millions		Dec. 31, 2020	Sep. 30, 2020
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Assets
Cash and cash equivalents		$ 335	$ 454
Restricted investments	[1]	346	331
Investment of captive insurance company	[2]	8	9
Foreign currency derivatives			1
Total assets at fair value		689	795
Liabilities
Foreign currency derivatives		1	3
Estimate of Fair Value, Fair Value Disclosure [Member]
Assets
Cash and cash equivalents		335	454
Restricted investments	[1]	346	331
Investment of captive insurance company	[2]	8	9
Foreign currency derivatives			1
Total assets at fair value		689	795
Liabilities
Foreign currency derivatives		1	3
Fair Value, Inputs, Level 1 [Member]
Assets
Cash and cash equivalents		335	454
Restricted investments	[1]	346	331
Investment of captive insurance company	[2]	8	9
Foreign currency derivatives			0
Total assets at fair value		689	794
Liabilities
Foreign currency derivatives		0	0
Fair Value, Inputs, Level 2 [Member]
Assets
Cash and cash equivalents		0	0
Restricted investments	[1]	0	0
Investment of captive insurance company	[2]	0	0
Foreign currency derivatives			1
Total assets at fair value		0	1
Liabilities
Foreign currency derivatives		1	3
Fair Value, Inputs, Level 3 [Member]
Assets
Cash and cash equivalents		0	0
Restricted investments	[1]	0	0
Investment of captive insurance company	[2]	0	0
Foreign currency derivatives			0
Total assets at fair value		0	0
Liabilities
Foreign currency derivatives		$ 0	$ 0
[1]	Included in restricted investments is $30 million classified in the other current assets caption on the Condensed Consolidated Balance Sheets.
[2]	Included in other noncurrent assets in the Condensed Consolidated Balance Sheets.

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Financial Instruments Subject to Recurring Fair Value Measurements (Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Restricted Investments, Current	$ 30	$ 30

Fair Value Measurements - Sum_3

Fair Value Measurements - Summary of Investment Portfolio (Details) - USD ($) $ in Millions		3 Months Ended			12 Months Ended
		Dec. 31, 2020		Dec. 31, 2019	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Original cost		$ 335			$ 335
Accumulated adjustments, net	[1]	(50)			(30)
Adjusted cost		285			305
Investment income		5	[2]	$ 4	10	[2]
Net unrealized gain	[3]	52			46
Realized gains	[3]	11			2
Settlement funds		1			3
Disbursements		(8)		$ (10)	(35)
Fair value		$ 346			$ 331
[1]	The accumulated adjustments include investment income, realized gains, disbursements and settlements recorded in previous periods.
[2]	Investment income for the demand deposit includes interest income as well as dividend income transferred from the equity and fixed income mutual funds.
[3]	Presented under the original cost method.

Fair Value Measurements - Sum_4

Fair Value Measurements - Summary of Available-for-sale Securities Portfolio (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Schedule of Available-for-sale Securities [Line Items]
Adjusted cost	$ 285	$ 305
Fair value	346	331
Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted cost	294	285
Fair value	346	331
Gross Unrealized Gain	52	47
Gross Unrealized Loss	0	(1)
Fixed Income Mutual Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted cost	184	162
Fair value	198	178
Gross Unrealized Gain	14	16
Gross Unrealized Loss	0	0
Equity Mutual Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted cost	101	116
Fair value	139	146
Gross Unrealized Gain	38	31
Gross Unrealized Loss	0	(1)
Demand Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted cost	9	7
Fair value	$ 9	$ 7

Fair Value Measurements - Sum_5

Fair Value Measurements - Summary of Investment Income, Net Gains and Losses Realized and Disbursements Related to Investments (Details) - USD ($) $ in Millions		3 Months Ended			12 Months Ended
		Dec. 31, 2020		Dec. 31, 2019	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Investment income		$ 5	[1]	$ 4	$ 10	[1]
Net gains (losses) unrealized	[2]	18		9
Disbursements		$ (8)		$ (10)	$ (35)
[1]	Investment income for the demand deposit includes interest income as well as dividend income transferred from the equity and fixed income mutual funds.
[2]	(a) Ashland determined that all unrealized gains and (losses) were related to equity securities with readily determinable fair values. Due to the new accounting guidance adopted in the first quarter of fiscal year 2019, the net unrealized gains and (losses) during the year ended September 30, 2019 and forward were recorded within the net interest and other expense caption in the Statements of Consolidated Income (Loss).

Fair Value Measurements - Sum_6

Fair Value Measurements - Summary of Net Gains and Losses on Foreign Currency Derivatives (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency derivative gains (losses)	$ 3	$ 1

Fair Value Measurements - Sum_7

Fair Value Measurements - Summary of Fair Values of Outstanding Foreign Currency Derivatives (Details) - Foreign Exchange Contract [Member] - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Accounts Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency derivative assets	$ 0	$ 1
Notional contract values	168	170
Accrued Expenses and Other Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional contract values	221	215
Foreign currency derivative liabilities	$ 1	$ 3

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Other financial instruments [Abstract]
Long-term debt, carrying value	$ 1,616	$ 1,588
Long-term debt, fair value	$ 1,806	$ 1,708

Inventories - Summary of Invent

Inventories - Summary of Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Inventory Disclosure [Abstract]
Finished products	$ 341	$ 336
Raw materials, supplies and work in process	196	193
Total	$ 537	$ 529

Goodwill and Other Intangible_2

Goodwill and Other Intangibles - Summary of Goodwill by Reportable Segment (Details) $ in Millions	3 Months Ended
	Dec. 31, 2020USD ($)
Goodwill [Roll Forward]
Balance at beginning of period	$ 1,758
Currency translation	34
Balance at end of period	1,792
Life Sciences [Member]
Goodwill [Roll Forward]
Balance at beginning of period	861
Currency translation	21
Balance at end of period	882
Personal Care & Household [Member]
Goodwill [Roll Forward]
Balance at beginning of period	0	[1]
Currency translation	0	[1]
Balance at end of period	0	[1]
Specialty Additives [Member]
Goodwill [Roll Forward]
Balance at beginning of period	444	[1]
Currency translation	13	[1]
Balance at end of period	457	[1]
Performance Adhesives [Member]
Goodwill [Roll Forward]
Balance at beginning of period	453
Currency translation	0
Balance at end of period	453
Intermediates and Solvents [Member]
Goodwill [Roll Forward]
Balance at beginning of period	0	[1]
Currency translation	0	[1]
Balance at end of period	$ 0	[1]
[1]	As of December 31, 2020 a nd September 30, 2020 , t here w ere accumulated impairment s of $ 356 million, $ 174 million and $ 90 million related to the Personal Care & Household, Specialty Additives and Intermediates and Solvents reportable segment s, respectively .

Goodwill and Other Intangible_3

Goodwill and Other Intangibles - Summary of Goodwill by Reportable Segment (Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Personal Care & Household [Member]
Goodwill [Line Items]
Accumulated impairment	$ 356	$ 356
Intermediates and Solvents [Member]
Goodwill [Line Items]
Accumulated impairment	90	90
Specialty Additives [Member]
Goodwill [Line Items]
Accumulated impairment	$ 174	$ 174

Goodwill and Other Intangible_4

Goodwill and Other Intangibles - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets, Net [Abstract]
Amortization expense recognized on intangible assets	$ 21	$ 21
Expected future amortization expense [Abstract]
2021 (includes three months actual and nine months estimated)	87
2022	86
2023	86
2024	72
2025	$ 69
Minimum [Member] | Trademarks and Trade Names [Member]
Intangible Assets, Net [Abstract]
Useful life (in years)	3 years
Minimum [Member] | Intellectual Property [Member]
Intangible Assets, Net [Abstract]
Useful life (in years)	5 years
Minimum [Member] | Customer and Supplier Relationships [Member]
Intangible Assets, Net [Abstract]
Useful life (in years)	3 years
Maximum [Member] | Trademarks and Trade Names [Member]
Intangible Assets, Net [Abstract]
Useful life (in years)	25 years
Maximum [Member] | Intellectual Property [Member]
Intangible Assets, Net [Abstract]
Useful life (in years)	25 years
Maximum [Member] | Customer and Supplier Relationships [Member]
Intangible Assets, Net [Abstract]
Useful life (in years)	24 years

Goodwill and Other Intangible_5

Goodwill and Other Intangibles - Summary of Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 1,567	$ 1,544
Accumulated amortization	(844)	(809)
Net carrying amount	723	735
Finite and Indefinite Intangible assets [Abstract]
Gross carrying amount	1,845	1,822
Net carrying amount	1,001	1,013
Trademarks and Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	66	66
Accumulated amortization	(33)	(32)
Net carrying amount	33	34
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Indefinite-lived intangible assets	278	278
Intellectual Property [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	731	721
Accumulated amortization	(460)	(442)
Net carrying amount	271	279
Customer and Supplier Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	770	757
Accumulated amortization	(351)	(335)
Net carrying amount	$ 419	$ 422

Debt - Summary of Current and L

Debt - Summary of Current and Long-term Debt (Details) - USD ($) $ in Millions		Dec. 31, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Carrying value of debt		$ 1,616	$ 1,588
Other	[1]	13	11
Total debt		1,694	1,853
Short-term debt (includes current portion of long-term debt)		(93)	(280)
Long-term debt (less current portion)		1,601	1,573
4.750% Notes due 2022 [Member]
Debt Instrument [Line Items]
Carrying value of debt		411	411
2.00% Senior Notes Due 2028 [Member]
Debt Instrument [Line Items]
Carrying value of debt		614	587
6.875% Notes due 2043 [Member]
Debt Instrument [Line Items]
Carrying value of debt		282	282
Term Loan A [Member]
Debt Instrument [Line Items]
Carrying value of debt		250	250
Accounts Receivable Securitization [Member]
Debt Instrument [Line Items]
Carrying value of debt		69	177
6.50% Junior Subordinated Notes, Due 2029 [Member]
Debt Instrument [Line Items]
Carrying value of debt		$ 55	55
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Carrying value of debt			$ 80
[1]	Includes $15 million of debt issuance cost discounts as of both December 31, 2020 and September 30, 2020. Additionally, as of December 31, 2020 and September 30, 2020, Other includes a European short-term loan facility with an outstanding balance of $24 million and $23 million, respectively.

Debt - Summary of Current and_2

Debt - Summary of Current and Long-term Debt (Parenthetical) (Details) € in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2020EUR (€)	Sep. 30, 2020USD ($)
Debt Instrument [Line Items]
Unamortized debt issuance expense, long-term debt	$ 15		$ 15
Short-term debt outstanding balance	$ 93		280
4.750% Notes due 2022 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	4.75%	4.75%
Debt instrument, maturity year	2022
2.00% Senior Notes Due 2028 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	2.00%	2.00%
Debt instrument, maturity year	2028
Principal amount | €		€ 500
6.875% Notes due 2043 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	6.875%	6.875%
Debt instrument, maturity year	2043
6.50% Junior Subordinated Notes, Due 2029 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	6.50%	6.50%
Debt instrument, maturity year	2029
European Facility [Member]
Debt Instrument [Line Items]
Short-term debt outstanding balance	$ 24		$ 23

Debt - Summary of Current and_3

Debt - Summary of Current and Long-term Debt - Additional Information (Details) $ in Millions	Jun. 30, 2020USD ($)
Scheduled aggregate debt maturities by fiscal year [Abstract]
2021	$ 0
2022	421
2023	22
2024	44
2025	$ 175

Debt - Financing Activity and C

Debt - Financing Activity and Covenants - Additional Information (Details) $ in Millions	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
Line of credit facility, remaining borrowing capacity	$ 694
Covenant restrictions [Abstract]
Maximum consolidated leverage ratio	4
Consolidated net leverage ratio	2.6
Minimum required consolidated interest coverage ratio	3
Consolidated interest coverage ratio	7.8
Accounts Receivable Securitization [Member]
Debt Instrument [Line Items]
Line of credit facility, remaining borrowing capacity	$ 114
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	600
Line of credit facility, remaining borrowing capacity	580
Letters of credit outstanding, amount	$ 20

Leasing Arrangements - Addition

Leasing Arrangements - Additional Information (Details) - USD ($)	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Lessee Lease Description [Line Items]
Weighted average remaining operating lease term	15 years		15 years
Weighted average operating discount rate, percent	2.90%		2.90%
Right-of-use assets exchanged for new operating lease obligations	$ 2,000,000
Maximum [Member]
Lessee Lease Description [Line Items]
Right-of-use assets exchanged for new operating lease obligations		$ 1,000,000
Real Estate [Member]
Lessee Lease Description [Line Items]
Operating lease liability percentage	89.00%

Leasing Arrangements - Componen

Leasing Arrangements - Components of Lease Cost Recognized (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lease cost:
Total lease cost	$ 9	$ 10
Selling General and Administrative Expenses {Member]
Lease cost:
Operating lease cost	3	5
Cost of Sales [Member]
Lease cost:
Operating lease cost	4	4
Variable lease cost	1	$ 1
Short-term leases	$ 1

Leasing Arrangements - Summary

Leasing Arrangements - Summary of Lease Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
ASSETS
Operating lease assets, net	$ 137	$ 137
Total lease assets	137	137
Liabilities
Current operating lease obligations	23	23
Non-current operating lease obligations	124	124
Total lease liabilities	$ 147	$ 147

Leasing Arrangements - Schedule

Leasing Arrangements - Schedule of Cash Paid for Amounts Included in the Measurement of Operating Lease Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating cash flows from operating leases	$ 7	$ 9

Leasing Arrangements - Schedu_2

Leasing Arrangements - Schedule of Maturities Analysis of Lease Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Leases [Abstract]
Remainder of 2021	$ 20	$ 28
2022	37	35
2023	17	17
2024	14	13
2025	12	11
Thereafter	90	88
Total lease payments	190	192
Less amount of lease payment representing interest	(43)	(45)
Total present value of lease payments	$ 147	$ 147

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Minimum [Member]
Income Tax Contingency [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	$ 50
Maximum [Member]
Income Tax Contingency [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	$ 60
Current Fiscal Year [Member]
Income Tax Contingency [Line Items]
Effective tax rate (in hundredths)	0.00%
Tax reform (benefit) and expense	$ (13)
Prior Fiscal Year [Member]
Income Tax Contingency [Line Items]
Effective tax rate (in hundredths)		(240.00%)
Prior Fiscal Year [Member] | Swiss Tax Reform [Member]
Income Tax Contingency [Line Items]
Tax reform (benefit) and expense		$ (27)

Income Taxes - Summary of Chang

Income Taxes - Summary of Changes in Unrecognized Tax Benefits (Details) $ in Millions	3 Months Ended
	Dec. 31, 2020USD ($)
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 171
Increases related to positions taken in the current year	7
Balance at end of period	$ 178

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Details) $ in Millions	3 Months Ended
	Dec. 31, 2020USD ($)
Foreign Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual contributions to benefit plans in period	$ 2
Estimated future contributions in current fiscal year	3
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual contributions to benefit plans in period	0
Estimated future contributions in current fiscal year	$ 2

Employee Benefit Plans - Schedu

Employee Benefit Plans - Schedule of Components of Pension and Other Postretirement Benefit Costs for Continuing Operation (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1
Interest cost	2	2
Expected return on plan assets	(2)	(3)
Curtailment	0	0
Total net periodic benefit costs (income)	1	0
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	0	1
Expected return on plan assets	0	0
Curtailment	0	0
Total net periodic benefit costs (income)	$ 0	$ 1

Litigation, Claims and Contin_3

Litigation, Claims and Contingencies - Summary of Asbestos Claims Activity (Details) - Claim Claim in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Ashland [Member]
Asbestos claims [Roll Forward]
Open claims - beginning of year	49	53	53	53	54
New claims filed	1	0	2	2	2
Claims settled	0	0	(1)	(1)	(1)
Claims dismissed	(1)	(2)	(5)	(1)	(2)
Open claims - end of period	49	51	49	53	53
Hercules [Member]
Asbestos claims [Roll Forward]
Open claims - beginning of year	12	13	13	13	12
New claims filed	1	0	1	1	2
Claims dismissed	(1)	0	(2)	(1)	(1)
Open claims - end of period	12	13	12	13	13

Litigation, Claims and Contin_4

Litigation, Claims and Contingencies - Additional Information (Details) $ in Millions		3 Months Ended			12 Months Ended
		Dec. 31, 2020USD ($)WasteTreatmentorDisposalSiteFacilityServiceStationProperty		Dec. 31, 2019USD ($)	Sep. 30, 2020USD ($)		Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)
Environmental Remediation Costs Recognized [Abstract]
Number of waste treatment or disposal sites were company is identified as a potentially responsible party under the superfund or similar state laws | WasteTreatmentorDisposalSite		82
Number of current and former operating facilities subject to various environmental laws | Facility		113
Total number of service station properties subject to various environmental laws | ServiceStationProperty		1,225
Number of service stations being actively remediated | ServiceStationProperty		24
Accrual for environmental loss contingencies		$ 195		$ 179	$ 200		$ 186
Accrued environmental loss contingencies, noncurrent		145			150
Recorded third-party environmental recoveries receivable		15			15
Recorded third-party environmental recoveries, noncurrent		$ 12			12
Maximum reserve for remediation reserve related to any one site (in hundredths)		14.00%
Minimum [Member]
Asbestos litigation cost projection [Abstract]
Number of Years Included in Asbestos Assumption		40 years
Maximum [Member]
Asbestos litigation cost projection [Abstract]
Number of Years Included in Asbestos Assumption		50 years
Environmental Remediation Costs Recognized [Abstract]
Environmental exit costs, reasonably possible additional loss		$ 470
Ashland [Member]
Asbestos reserve [Roll Forward]
Increase (decrease) in asbestos related reserve		0		0	13		1	$ (8)
Total reserves for asbestos claims		325	[1]	342	335	[1]	352	380	$ 419
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Insurance receivable		98	[2]	122	103	[2]	123	140	155
Receivable adjustment	[3]	(2)		0	1		(5)	(5)
Asbestos litigation cost projection [Abstract]
Possible total future litigation defense and claim settlement costs		520
Total reserves for asbestos claims		325	[1]	342	335	[1]	352	380	419
Hercules [Member]
Asbestos reserve [Roll Forward]
Increase (decrease) in asbestos related reserve		0		0	(3)		(10)	(19)
Total reserves for asbestos claims		224	[4]	247	229	[4]	252	282	323
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Insurance receivable		46		49	47		49	54	68
Receivable adjustment		(1)		0	(2)		(5)	(14)
Asbestos litigation cost projection [Abstract]
Possible total future litigation defense and claim settlement costs		350
Total reserves for asbestos claims		$ 224	[4]	$ 247	$ 229	[4]	$ 252	$ 282	$ 323
[1]	Included $ million classified in accrued expenses and other liabilities on the Condensed Consolidated Balance Sheets as of both December 31, 2020 and September 30, 2020 .
[2]	Included
[3]	The three months ended December 31, 2020 includes a $2 million adjustment related to allowances for credit losses as a result of Ashland’s adoption of the new credit measurement standard described in Note A.
[4]	Included

Litigation, Claims and Contin_5

Litigation, Claims and Contingencies - Schedule of Progression of Activity in the Asbestos Reserve (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2020		Dec. 31, 2019	Sep. 30, 2020		Sep. 30, 2019	Sep. 30, 2018
Ashland [Member]
Asbestos reserve [Roll Forward]
Asbestos reserve - beginning of year	$ 335	[1]	$ 352	$ 352		$ 380	$ 419
Reserve adjustment	0		0	13		1	(8)
Amounts paid	(10)		(10)	(30)		(29)	(31)
Asbestos reserve - end of period	325	[1]	342	335	[1]	352	380
Hercules [Member]
Asbestos reserve [Roll Forward]
Asbestos reserve - beginning of year	229	[2]	252	252		282	323
Reserve adjustment	0		0	(3)		(10)	(19)
Amounts paid	(5)		(5)	(20)		(20)	(22)
Asbestos reserve - end of period	$ 224	[2]	$ 247	$ 229	[2]	$ 252	$ 282
[1]	Included $ million classified in accrued expenses and other liabilities on the Condensed Consolidated Balance Sheets as of both December 31, 2020 and September 30, 2020 .
[2]	Included

Litigation, Claims and Contin_6

Litigation, Claims and Contingencies - Schedule of Progression of Activity in the Asbestos Reserve (Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2020		Sep. 30, 2020		Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Ashland [Member]
Asbestos reserve [Roll Forward]
Asbestos reserve	$ 325	[1]	$ 335	[1]	$ 342	$ 352	$ 380	$ 419
Ashland [Member] | Other Current Liabilities [Member]
Asbestos reserve [Roll Forward]
Asbestos reserve	29		29
Hercules [Member]
Asbestos reserve [Roll Forward]
Asbestos reserve	224	[2]	229	[2]	$ 247	$ 252	$ 282	$ 323
Hercules [Member] | Other Current Liabilities [Member]
Asbestos reserve [Roll Forward]
Asbestos reserve	$ 22		$ 22
[1]	Included $ million classified in accrued expenses and other liabilities on the Condensed Consolidated Balance Sheets as of both December 31, 2020 and September 30, 2020 .
[2]	Included

Litigation, Claims and Contin_7

Litigation, Claims and Contingencies - Summary of Progression of Insurance Receivable (Details) - USD ($) $ in Millions		3 Months Ended			12 Months Ended
		Dec. 31, 2020		Dec. 31, 2019	Sep. 30, 2020		Sep. 30, 2019	Sep. 30, 2018
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Insurance settlement		$ 1		$ 0
Ashland [Member]
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Insurance receivable - beginning of year		103	[1]	123	$ 123		$ 140	$ 155
Receivable adjustment	[2]	(2)		0	1		(5)	(5)
Insurance settlement		0		0	(10)		0	0
Amounts collected		(3)		(1)	(11)		(12)	(10)
Insurance receivable - end of period		98	[1]	122	103	[1]	123	140
Hercules [Member]
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Insurance receivable - beginning of year		47		49	49		54	68
Receivable adjustment		(1)		0	(2)		(5)	(14)
Insurance receivable - end of period		$ 46		$ 49	$ 47		$ 49	$ 54
[1]	Included
[2]	The three months ended December 31, 2020 includes a $2 million adjustment related to allowances for credit losses as a result of Ashland’s adoption of the new credit measurement standard described in Note A.

Litigation, Claims and Contin_8

Litigation, Claims and Contingencies - Summary of Progression of Insurance Receivable (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020		Sep. 30, 2020		Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Ashland [Member]
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Insurance receivable	$ 98	[1]	$ 103	[1]	$ 122	$ 123	$ 140	$ 155
Ashland [Member] | Accounts Receivable [Member]
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Allowance for credit losses	2
Insurance receivable	14		14
Hercules [Member]
Movement in Loss Contingency Receivable, Increase (Decrease) [Roll Forward]
Allowance for credit losses	1
Insurance receivable	$ 46		$ 47		$ 49	$ 49	$ 54	$ 68
[1]	Included

Litigation, Claims and Contin_9

Litigation, Claims and Contingencies - Summary of Reconciliation of Changes in Environmental Remediation Reserves (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Environmental Remediation Obligations [Abstract]
Reserve - beginning of period	$ 200	$ 186
Disbursements	(10)	(9)
Revised obligation estimates and accretion	5	2
Reserve - end of period	$ 195	$ 179

Litigation, Claims and Conti_10

Litigation, Claims and Contingencies - Summary of Components of Environmental Remediation Expense Included within Selling, General and Administrative Expense (Details) - USD ($) $ in Millions		3 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Environmental Expense And Liabilities [Abstract]
Environmental expense		$ 5	$ 2
Accretion		0	0
Legal expense		1	2
Total expense		6	4
Insurance receivable		(1)	0
Total expense, net of receivable activity	[1]	$ 5	$ 4
[1]	Net expense of $1 million for the three months ended December 31, 2020, relates to divested businesses which qualified for treatment as discontinued operations for which certain environmental liabilities were retained by Ashland. These amounts are classified within the income from discontinued operations caption of the Statements of Consolidated Comprehensive Income (loss).

Litigation, Claims and Conti_11

Litigation, Claims and Contingencies - Summary of Components of Environmental Remediation Expense Included within Selling, General and Administrative Expense (Parenthetical) (Details) $ in Millions	3 Months Ended
	Dec. 31, 2020USD ($)
Environmental Expense And Liabilities [Abstract]
Net expense relates to divested businesses	$ 1

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Details) - shares shares in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Antidilutive securities excluded from calculation of earnings per share	2	2

Earnings Per Share - Computatio

Earnings Per Share - Computation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Numerator
Numerator for basic and diluted EPS - Income (loss) from continuing operations	$ 61	$ 34
Denominator
Denominator for basic EPS - Weighted-average common shares outstanding	60	60
Share based awards convertible to common shares	1	1
Denominator for diluted EPS - Adjusted weighted-average shares and assumed conversions	61	61
EPS from continuing operations
Basic	$ 1	$ 0.57
Diluted	$ 0.99	$ 0.56

Equity Items - Additional Infor

Equity Items - Additional Information (Details) - $ / shares	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Equity [Abstract]
Dividend per common share	$ 0.275	$ 0.275

Equity Items - Components of Ac

Equity Items - Components of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Equity [Abstract]
Unrealized translation gain, before tax	$ 48	$ 38
Unrealized translation gain, net of tax	48	38
Total other comprehensive income, before tax	48	38
Other comprehensive income	$ 48	$ 38

Equity Items - Summary of Recon

Equity Items - Summary of Reconciliation of Changes in Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Balance, end of period		$ 3,122	$ 3,625
Cash dividends declared per common share		$ 0.275	$ 0.275
Common Stock and Paid in Capital [Member]
Balance, beginning of period		$ 770	$ 757
Common shares issued under stock incentive and other plans	[1]	1	1
Balance, end of period		771	758
Retained earnings [Member]
Balance, beginning of period		2,649	3,224
Adoption of new accounting pronouncements		(2)
Net income		56	32
Regular dividends		(17)	(17)
Balance, end of period		2,686	3,239
Accumulated other comprehensive income (loss) [Member]
Balance, beginning of period		(383)	(410)
Unrealized translation gain		48	38
Balance, end of period		$ (335)	$ (372)
[1]	Common shares issued were 99,194 shares and 70,461 shares for the three months ended December 31, 2020 and 2019, respectively.

Equity Items - Summary of Rec_2

Equity Items - Summary of Reconciliation of Changes in Stockholders' Equity (Parenthetical) (Details) - shares	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Equity [Abstract]
Common shares issued	99,194	70,461

Stock Incentive Plans - Compone

Stock Incentive Plans - Components of Pretax Stock-Based Compensation Expense Included in Continuing Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	[1]	Dec. 31, 2019	[2]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 5		$ 5
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	1		2
Nonvested Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	2		2
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 2		$ 1
[1]	Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2020.
[2]	Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2019.

Stock Incentive Plans - Compo_2

Stock Incentive Plans - Components of Pretax Stock-Based Compensation Expense Included in Continuing Operations (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020		Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 5	[1]	$ 5	[2]
Cash-settled Nonvested Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	1		1
Cash-settled Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 0		$ 0
[1]	Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2020.
[2]	Included $1 million of expense related to cash-settled nonvested restricted stock awards and zero related to cash-settled performance units during the three months ended December 31, 2019.

Revenue - Additional Informatio

Revenue - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Sep. 30, 2020
Revenue From Contracts With Customers [Line Items]
Maximum cash collection period from customer	60 days
Cost incurred to obtain contract with customer amortization period of practical expedients	true
Trade Receivable [Member]
Revenue From Contracts With Customers [Line Items]
Trade receivables	$ 383	$ 441

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Sales	$ 552	$ 533
Life Sciences [Member]
Disaggregation Of Revenue [Line Items]
Sales	170	155
Life Sciences [Member] | North America [Member]
Disaggregation Of Revenue [Line Items]
Sales	51	49
Life Sciences [Member] | Europe [Member]
Disaggregation Of Revenue [Line Items]
Sales	54	49
Life Sciences [Member] | Asia Pacific [Member]
Disaggregation Of Revenue [Line Items]
Sales	47	42
Life Sciences [Member] | Latin America & Other [Member]
Disaggregation Of Revenue [Line Items]
Sales	18	15
Personal Care & Household [Member]
Disaggregation Of Revenue [Line Items]
Sales	126	137
Personal Care & Household [Member] | North America [Member]
Disaggregation Of Revenue [Line Items]
Sales	41	41
Personal Care & Household [Member] | Europe [Member]
Disaggregation Of Revenue [Line Items]
Sales	46	55
Personal Care & Household [Member] | Asia Pacific [Member]
Disaggregation Of Revenue [Line Items]
Sales	21	24
Personal Care & Household [Member] | Latin America & Other [Member]
Disaggregation Of Revenue [Line Items]
Sales	18	17
Specialty Additives [Member]
Disaggregation Of Revenue [Line Items]
Sales	147	139
Specialty Additives [Member] | North America [Member]
Disaggregation Of Revenue [Line Items]
Sales	45	45
Specialty Additives [Member] | Europe [Member]
Disaggregation Of Revenue [Line Items]
Sales	52	50
Specialty Additives [Member] | Asia Pacific [Member]
Disaggregation Of Revenue [Line Items]
Sales	41	35
Specialty Additives [Member] | Latin America & Other [Member]
Disaggregation Of Revenue [Line Items]
Sales	9	9
Performance Adhesives [Member]
Disaggregation Of Revenue [Line Items]
Sales	84	74
Performance Adhesives [Member] | North America [Member]
Disaggregation Of Revenue [Line Items]
Sales	68	64
Performance Adhesives [Member] | Europe [Member]
Disaggregation Of Revenue [Line Items]
Sales	10	7
Performance Adhesives [Member] | Asia Pacific [Member]
Disaggregation Of Revenue [Line Items]
Sales	4	2
Performance Adhesives [Member] | Latin America & Other [Member]
Disaggregation Of Revenue [Line Items]
Sales	2	1
Intermediates and Solvents [Member]
Disaggregation Of Revenue [Line Items]
Sales	33	28
Intermediates and Solvents [Member] | North America [Member]
Disaggregation Of Revenue [Line Items]
Sales	21	15
Intermediates and Solvents [Member] | Europe [Member]
Disaggregation Of Revenue [Line Items]
Sales	4	5
Intermediates and Solvents [Member] | Asia Pacific [Member]
Disaggregation Of Revenue [Line Items]
Sales	7	7
Intermediates and Solvents [Member] | Latin America & Other [Member]
Disaggregation Of Revenue [Line Items]
Sales	$ 1	$ 1

Reportable Segment Informatio_2

Reportable Segment Information - Summary of Financial Information for Each Reportable Segment (Details) - USD ($) $ in Millions		3 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Segment Reporting Information [Line Items]
Sales		$ 552	$ 533
OPERATING INCOME (LOSS)		41	17
DEPRECIATION EXPENSE		41	40
AMORTIZATION EXPENSE		21	21
EBITDA	[1]	103	78
TOTAL ASSETS		6,742		$ 6,877
Life Sciences [Member]
Segment Reporting Information [Line Items]
Sales		170	155
OPERATING INCOME (LOSS)		29	22
DEPRECIATION EXPENSE		9	8
AMORTIZATION EXPENSE		7	7
EBITDA	[1]	45	37
TOTAL ASSETS		1,987		1,974
Personal Care & Household [Member]
Segment Reporting Information [Line Items]
Sales		126	137
OPERATING INCOME (LOSS)		15	11
DEPRECIATION EXPENSE		10	10
AMORTIZATION EXPENSE		9	9
EBITDA	[1]	34	30
TOTAL ASSETS		904		939
Consumer Specialties [Member]
Segment Reporting Information [Line Items]
Sales		296	292
OPERATING INCOME (LOSS)		44	33
DEPRECIATION EXPENSE		19	18
AMORTIZATION EXPENSE		16	16
EBITDA	[1]	79	67
TOTAL ASSETS		2,891		2,913
Specialty Additives [Member]
Segment Reporting Information [Line Items]
Sales		147	139
OPERATING INCOME (LOSS)	[2]	2	9
DEPRECIATION EXPENSE		16	15
AMORTIZATION EXPENSE		5	5
EBITDA	[1]	23	29
TOTAL ASSETS		1,662		1,666
Performance Adhesives [Member]
Segment Reporting Information [Line Items]
Sales		84	74
OPERATING INCOME (LOSS)		20	10
DEPRECIATION EXPENSE		3	4
EBITDA	[1]	23	14
TOTAL ASSETS		594		591
Industrial Specialties [Member]
Segment Reporting Information [Line Items]
Sales		231	213
OPERATING INCOME (LOSS)		22	19
DEPRECIATION EXPENSE		19	19
AMORTIZATION EXPENSE		5	5
EBITDA	[1]	46	43
TOTAL ASSETS		2,256		2,257
Intermediates and Solvents [Member]
Segment Reporting Information [Line Items]
Sales		33	28
OPERATING INCOME (LOSS)		2	(12)
DEPRECIATION EXPENSE		3	3
EBITDA	[1]	5	(9)
TOTAL ASSETS		158		161
Intermediates and Solvents [Member] | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales	[3]	(8)
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
OPERATING INCOME (LOSS)		(27)	(23)
EBITDA	[1]	(27)	$ (23)
TOTAL ASSETS		$ 1,437		$ 1,546
[1]	Excludes income (loss) from discontinued operations, other net periodic benefit income (expense) and net income (loss) on divestitures. See the Statement of Consolidated Comprehensive Income (Loss) for applicable amounts excluded.
[2]	Includes a capital project impairment of $9 million for the three months ended December 31, 2020 relating to a long-term capital project plan change at a plant facility.
[3]	Intersegment sales from Intermediates and Solvents are accounted for at prices that approximate fair value. All other intersegment sales are accounted for at cost.

Reportable Segment Informatio_3

Reportable Segment Information - Summary of Financial Information for Each Reportable Segment (Parenthetical) (Details) $ in Millions	3 Months Ended
	Dec. 31, 2020USD ($)
Specialty Additives [Member]
Segment Reporting Information [Line Items]
Capital project impairment	$ 9

Subsequent Events - Additional

Subsequent Events - Additional Information (Details) € in Millions	Jan. 19, 2021EUR (€)
Subsequent Event [Member] | Schülke & Mayr GmbH [Member]
Subsequent Event [Line Items]
Payments to acquire business	€ 262.5