ENVIRONMENTAL LIABILITIES AND EXPENDITURES (Details)	1 Months Ended		3 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Mar. 31, 2016 mi	Sep. 30, 2016 USD ($)	Dec. 31, 2021 USD ($) site	Dec. 31, 2020 USD ($) site	Dec. 31, 2019 USD ($)
Environmental remediation reserves
Number of sites				165	170
Environmental remediation reserves, current, included in accrued liabilities | $				$ 155,000,000	$ 123,000,000
Environmental remediation reserves, noncurrent, included in deferred credits and other liabilities - other | $				944,000,000	1,028,000,000
Remediation balance | $				1,099,000,000	1,151,000,000
Environmental reserves, exceeding $ ten million, threshold value | $				$ 10,000,000
Environmental reserves, exceeding $ ten million, number of sites				20
Environmental reserves, range between zero to $ one million site category, number of sites				96
Remediation Expenses | $				$ 28,000,000	$ 36,000,000	$ 112,000,000
Percent of reserve to be funded over the next three to four years				40.00%
Minimum period of expending second half of environmental reserves				10 years
Environmental remediation additional loss range | $				$ 1,300,000,000
Low end of range
Environmental remediation reserves
Environmental reserves, range between zero to $ one million site category | $				$ 0
Period of expending 40 percent of environmental reserves				3 years
High end of range
Environmental remediation reserves
Environmental reserves, range between zero to $ one million site category | $				$ 1,000,000
Period of expending 40 percent of environmental reserves				4 years
NPL sites
Environmental remediation reserves
Number of sites				30	35
Remediation balance | $				$ 427,000,000	$ 447,000,000
Number of sites with significant environmental remediation reserves				4
Percentage of environmental reserves accounted for by associated sites				96.00%
Number of sites indemnified by third party				14
Third-party sites
Environmental remediation reserves
Number of sites				69	69
Remediation balance | $				$ 273,000,000	$ 293,000,000
Number of sites with significant environmental remediation reserves				10
Percentage of environmental reserves accounted for by associated sites				75.00%
Number of sites indemnified by third party				69
Number of sites not indemnified by third party				69
Occidental-operated sites
Environmental remediation reserves
Number of sites				15	17
Remediation balance | $				$ 122,000,000	$ 144,000,000
Number of sites with significant environmental remediation reserves				2
Percentage of environmental reserves accounted for by associated sites				69.00%
Closed or non-operated Occidental sites
Environmental remediation reserves
Number of sites				51	49
Remediation balance | $				$ 277,000,000	$ 267,000,000
Number of sites with significant environmental remediation reserves				5
Percentage of environmental reserves accounted for by associated sites				75.00%
Maxus
Environmental remediation reserves
Number of sites indemnified by third party				9
Passaic River
Environmental remediation reserves
Stretch of Lower Passaic river requiring remedial actions | mi		8.3
River stretch which may require remedial actions | mi		9
Clean-up estimated cost | $	$ 441,000,000		$ 165,000,000