XML 117 R103.htm IDEA: XBRL DOCUMENT v3.25.3

Income Taxes - Expiration Dates of NOLs, Capital Loss and Other Tax Credit Carryforwards Before Valuation Allowances (Detail) $ in Millions	Sep. 30, 2025 USD ($)
Significant Tax Attributes And Dates Of Expiration [Line Items]
NOLs/Capital Losses	$ 2,237
Credits	140
2026 - 2032 [Member]
Significant Tax Attributes And Dates Of Expiration [Line Items]
NOLs/Capital Losses	1,014
Credits	76
2033 and thereafter [Member]
Significant Tax Attributes And Dates Of Expiration [Line Items]
NOLs/Capital Losses	308
Credits	62
Indefinite Carryforwards [Member]
Significant Tax Attributes And Dates Of Expiration [Line Items]
NOLs/Capital Losses	915
Credits	$ 2

X

- Definition

Operating loss and capital losses carryforwards.

+ References

No definition available.

+ Details

Name:	cbt_OperatingLossAndCapitalLossesCarryforwards
Namespace Prefix:	cbt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Significant tax attributes and dates of expiration.

+ References

No definition available.

+ Details

Name:	cbt_SignificantTaxAttributesAndDatesOfExpirationLineItems
Namespace Prefix:	cbt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

+ Details

Name:	us-gaap_TaxCreditCarryforwardAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_TaxPeriodAxis=cbt_TwoThousandTwentySixToTwoThousandThirtyTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_TaxPeriodAxis=cbt_TwoThousandThirtyThreeAndThereAfterMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_TaxPeriodAxis=cbt_IndefiniteCarryforwardMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: