LONG-TERM DEBT - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Long-term Debt
Long-term debt, gross	$ 17,936	$ 17,958
Unamortized premium, net	1,239	1,261
Debt issuance costs	(70)	(73)
Net book value of debt	19,105	19,146
Finance lease liabilities, non-current	540	546
Current finance leases	139	143
Total debt and finance leases	19,784	19,835
Less: current maturities of financing leases	(139)	(143)
Less: current maturities of long-term debt	0	(22)
Long-term debt, net	$ 19,645	19,670
8.750% medium-term notes due 2023 \| Medium-term Notes
Long-term Debt
Debt instrument interest rate stated percentage	8.75%
Long-term debt, gross	$ 0	22
2.900% senior notes due 2024 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	2.90%
Long-term debt, gross	$ 654	654
6.950% senior notes due 2024 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	6.95%
Long-term debt, gross	$ 291	291
3.450% senior notes due 2024 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	3.45%
Long-term debt, gross	$ 111	111
5.875% senior notes due 2025 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	5.875%
Long-term debt, gross	$ 606	606
3.500% senior notes due 2025 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	3.50%
Long-term debt, gross	$ 137	137
5.500% senior notes due 2025 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	5.50%
Long-term debt, gross	$ 465	465
5.550% senior notes due 2026 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	5.55%
Long-term debt, gross	$ 870	870
3.200% senior notes due 2026 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	3.20%
Long-term debt, gross	$ 182	182
3.400% senior notes due 2026 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	3.40%
Long-term debt, gross	$ 284	284
7.500% debentures due 2026 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.50%
Long-term debt, gross	$ 112	112
8.500% senior notes due 2027 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	8.50%
Long-term debt, gross	$ 489	489
3.000% senior notes due 2027 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	3.00%
Long-term debt, gross	$ 216	216
7.125% debentures due 2027 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.125%
Long-term debt, gross	$ 150	150
7.000% debentures due 2027 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.00%
Long-term debt, gross	$ 48	48
6.625% debentures due 2028 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	6.625%
Long-term debt, gross	$ 14	14
7.150% debentures due 2028 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.15%
Long-term debt, gross	$ 232	232
7.200% senior debentures due 2028 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	7.20%
Long-term debt, gross	$ 82	82
6.375% senior notes due 2028 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	6.375%
Long-term debt, gross	$ 578	578
7.200% debentures due 2029 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.20%
Long-term debt, gross	$ 135	135
7.950% debentures due 2029 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.95%
Long-term debt, gross	$ 116	116
8.450% senior notes due 2029 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	8.45%
Long-term debt, gross	$ 116	116
3.500% senior notes due 2029 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	3.50%
Long-term debt, gross	$ 286	$ 286
Variable rate bonds due 2030 (5.480% and 5.320% as of March 31, 2023 and December 31, 2022, respectively) \| Variable Rate Bonds
Long-term Debt
Debt instrument, variable rate	5.48%	5.32%
Long-term debt, gross	$ 68	$ 68
8.875% senior notes due 2030 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	8.875%
Long-term debt, gross	$ 1,000	1,000
6.625% senior notes due 2030 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	6.625%
Long-term debt, gross	$ 1,449	1,449
6.125% senior notes due 2031 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	6.125%
Long-term debt, gross	$ 1,143	1,143
7.500% senior notes due 2031 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	7.50%
Long-term debt, gross	$ 900	900
7.875% senior notes due 2031 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	7.875%
Long-term debt, gross	$ 500	500
6.450% senior notes due 2036 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	6.45%
Long-term debt, gross	$ 1,727	1,727
Zero Coupon senior notes due 2036 \| Senior Notes
Long-term Debt
Long-term debt, gross	$ 673	673
4.300% senior notes due 2039 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	4.30%
Long-term debt, gross	$ 247	247
7.950% senior notes due 2039 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	7.95%
Long-term debt, gross	$ 325	325
6.200% senior notes due 2040 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	6.20%
Long-term debt, gross	$ 737	737
4.500% senior notes due 2044 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	4.50%
Long-term debt, gross	$ 191	191
4.625% senior notes due 2045 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	4.625%
Long-term debt, gross	$ 296	296
6.600% senior notes due 2046 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	6.60%
Long-term debt, gross	$ 1,117	1,117
4.400% senior notes due 2046 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	4.40%
Long-term debt, gross	$ 424	424
4.100% senior notes due 2047 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	4.10%
Long-term debt, gross	$ 258	258
4.200% senior notes due 2048 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	4.20%
Long-term debt, gross	$ 304	304
4.400% senior notes due 2049 \| Senior Notes
Long-term Debt
Debt instrument interest rate stated percentage	4.40%
Long-term debt, gross	$ 280	280
7.730% debentures due 2096 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.73%
Long-term debt, gross	$ 58	58
7.500% debentures due 2096 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.50%
Long-term debt, gross	$ 60	60
7.250% debentures due 2096 \| Debentures
Long-term Debt
Debt instrument interest rate stated percentage	7.25%
Long-term debt, gross	$ 5	$ 5

Finance Lease, Liability, Current Maturities

No definition available.

Name:	oxy_FinanceLeaseLiabilityCurrentMaturities
Namespace Prefix:	oxy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Long-term Debt, Current Maturities Excluding Finance Leases

+ References

No definition available.

+ Details

Name:	oxy_LongTermDebtCurrentMaturitiesExcludingFinanceLeases
Namespace Prefix:	oxy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Amount, after accumulated amortization, of debt discount (premium).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28567-108399

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

+ Details

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

- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

+ Details

Name:	us-gaap_FinanceLeaseLiabilityCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

+ References

+ Details

Name:	us-gaap_FinanceLeaseLiabilityNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of long-term debt and lease obligation, including portion classified as current.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant