SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
RISKS AND UNCERTAINTIES
Assets, relating to operations in countries outside North America	$ 15,000,000,000
Net sales, relating to operations in countries outside North America	7,300,000,000
CASH AND CASH EQUIVALENTS
Total cash equivalents	3,400,000,000	2,900,000,000
RESTRICTED CASH
Restricted cash	4,019,000,000
Restricted cash useage term (in months)	18 months
PROPERTY, PLANT AND EQUIPMENT
Maximum time period after which costs of exploratory wells are charged to expense if determination of proved reserves has not been made	12 months	12 months	12 months
Net capitalized costs attributable to unproved properties	2,000,000,000
Capitalized exploratory well costs for the years ended December 31:
Balance - Beginning of Year	140,000,000	124,000,000	189,000,000
Additions to capitalized exploratory well costs pending the determination of proved reserves	462,000,000	337,000,000	400,000,000
Reclassifications to property, plant and equipment based on the determination of proved reserves	(423,000,000)	(271,000,000)	(389,000,000)
Spin-off of California Resources	(17,000,000)
Capitalized exploratory well costs charged to expense	(21,000,000)	(50,000,000)	(76,000,000)
Balance - End of Year	141,000,000	140,000,000	124,000,000
ACCRUED LIABILITIES-CURRENT
Accrued liabilities for accrued payroll, commissions and related expenses	361,000,000	459,000,000
ENVIRONMENTAL LIABILITIES AND EXPENDITURES
Minimum period of investigation and cleanup for Comprehensive Environmental Response, Compensation and Liability Act National Priorities List sites	10 years	10 years	10 years
ASSET RETIREMENT OBLIGATIONS
Asset retirement obligation, included in deferred credits and other liabilities-other	1,024,000,000	1,283,000,000
For the years ended December 31
Beginning balance	1,332,000,000	1,266,000,000
Liabilities incurred - capitalized to PP&E	57,000,000	101,000,000
Liabilities settled and paid	(78,000,000)	(72,000,000)
Accretion expense	69,000,000	68,000,000
Acquisitions, dispositions and other - changes in PP&E	(11,000,000)	(10,000,000)
Spin-off of California Resources	(399,000,000)
Revisions to estimated cash flows - changes in PP&E	121,000,000	(21,000,000)
Ending balance	1,091,000,000	1,332,000,000	1,266,000,000
SUPPLEMENTAL CASH FLOW INFORMATION
Interest Paid	219,000,000	238,000,000	190,000,000
Capitalized interest	180,000,000	137,000,000	100,000,000
Low end of range
Summary of significant accounting policies
The estimated useful lives of Occidental's chemical assets	3 years
DERIVATIVE INSTRUMENTS
Range used to determine if derivative instrument is effective	80.00%
High end of range
Summary of significant accounting policies
The estimated useful lives of Occidental's chemical assets	50 years
DERIVATIVE INSTRUMENTS
Range used to determine if derivative instrument is effective	125.00%
Continuing operations
SUPPLEMENTAL CASH FLOW INFORMATION
United States federal, state and foreign income taxes paid for continuing operations	2,900,000,000	1,800,000,000	2,300,000,000
Production, property and other taxes paid	$ 610,000,000	$ 606,000,000	$ 524,000,000