Acquisition	9 Months Ended
Jun. 30, 2023
Business Combinations [Abstract]
Acquisition	C. Acquisition Tokai Carbon (Tianjin) Co. In February 2022, the Company purchased 100% of the registered capital of Tokai Carbon (Tianjin) Co., a carbon black manufacturing facility, from Tokai Carbon Group for a net purchase price of $9 million, consisting of cash consideration of $14 million, including customary post-closing adjustments, and net of $5 million of cash acquired. The excess of the fair value of the net assets over the purchase price was recorded as a gain of $24 million for the three months ended March 31, 2022. The Gain on bargain purchase of a business arose primarily due to equipment upgrades required after the purchase to continue to utilize the existing assets.

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479907/805-20-50-5

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 805
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//805/tableOfContent

Name:	us-gaap_BusinessCombinationDisclosureTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration