The percentage of litigation award claimed by third party.

No definition available.

Name:	oxy_PercentageOfLitigationSettlementClaimed
Namespace Prefix:	oxy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of economic interest owned.

+ References

No definition available.

+ Details

Name:	oxy_PercentageOfOwnEconomicInterest
Namespace Prefix:	oxy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of award to the recovery value of property.

+ References

No definition available.

+ Details

Name:	oxy_PercentageOfRecoveryAmountAwardedInSettlementAmount
Namespace Prefix:	oxy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermPurchaseCommitmentAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermPurchaseCommitmentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LongtermPurchaseCommitmentPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585

+ Details

Name:	us-gaap_ProceedsFromLegalSettlements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	srt_LitigationCaseAxis=oxy_ArbitrationDemandFiledByAndesPetroleumEcuadorLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Lawsuits, Claims, Commitments and Contingencies (Details) - USD ($) $ in Billions	3 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Lawsuits, commitments and contingencies
Long-term purchase commitment	$ 2.0
Long-term purchase commitment, term	10 years
Arbitration filed by Andes Petroleum Ecuador Ltd
Lawsuits, commitments and contingencies
Proceeds from settlement			$ 1.0
Recovery of amount awarded in settlement amount (as a percent)			60.00%
Percentage of judgment amount claimed		40.00%
Own economic interest (as a percent)		60.00%