XML 49 R76.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Litigation, Claims and Contingencies - Summary of Asbestos Claims Activity (Details) - Claim Claim in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2017
Ashland [Member] |  |  |  |  |
Asbestos claims [Roll Forward] |  |  |  |  |
Open claims - beginning of year | 53 | 53 | 53 | 54 | 57
New claims filed | 0 | 1 | 2 | 2 | 2
Claims settled | 0 | (1) | (1) | (1) | (1)
Claims dismissed | (2) | 0 | (1) | (2) | (4)
Open claims - end of period | 51 | 53 | 53 | 53 | 54
Hercules [Member] |  |  |  |  |
Asbestos claims [Roll Forward] |  |  |  |  |
Open claims - beginning of year | 13 | 13 | 13 | 12 | 15
New claims filed |  |  | 1 | 2 | 1
Claims dismissed |  | (1) | (1) | (1) | (4)
Open claims - end of period | 13 | 12 | 13 | 13 | 12

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | ash_AsbestosClaimsRollForward
Namespace Prefix: | ash_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of claims dismissed. + References No definition available. + Details
Name: | us-gaap_LossContingencyClaimsDismissedNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of claims settled. + References No definition available. + Details
Name: | us-gaap_LossContingencyClaimsSettledNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The total number of new claims filed pertaining to a loss contingency during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349 + Details
Name: | us-gaap_LossContingencyNewClaimsFiledNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349 + Details
Name: | us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=ash_AshlandGlobalHoldingsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=ash_HerculesLimitedLiabilityCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |