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ACQUISITIONS, DISPOSITIONS AND OTHER TRANSACTIONS (Details 1) $ in Millions, lb in Billions			1 Months Ended										12 Months Ended
	Nov. 30, 2014 USD ($)	May. 15, 2013 USD ($)	Jan. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Nov. 30, 2015 USD ($)	Oct. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) a	Nov. 30, 2014 USD ($)	Apr. 30, 2014 USD ($)	Feb. 28, 2014 USD ($)	Oct. 31, 2013 USD ($) lb	May. 31, 2013 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Acquisitions, dispositions and other transactions
Gain on sale of idled site													$ 98
Total portion of construction costs				$ 530									$ 530
Charge for former employees and consultants		$ 55
Spin-off California Resources Corp
Acquisitions, dispositions and other transactions
Percentage of common stock distributed	81.30%							81.30%
Permian region
Acquisitions, dispositions and other transactions
Cash paid on acquisition							$ 1,300							$ 1,300
Number of acres acquired \| a							100,000
Domestic Oil and Gas Properties
Acquisitions, dispositions and other transactions
Acquisition of oil and gas properties															$ 500
Brazilian chemical facility
Acquisitions, dispositions and other transactions
Pre-tax proceeds from sale of assets												$ 270
Gain on sale of equity investments												$ 131
General Partner of Plains All American Pipeline,L.P
Acquisitions, dispositions and other transactions
Sale of equity investment								$ 1,700			$ 1,400
Gain on sale of equity investments								$ 1,400			$ 1,000
Ingleside
Acquisitions, dispositions and other transactions
Ethylene production capacity of ethane steam cracking unit, per year (in pounds) \| lb											1.2
BridgeTex
Acquisitions, dispositions and other transactions
Number of transactions involved in sale								2
Sale of equity investment	$ 75							$ 1,075
Gain on sale of equity investments	$ 633													633
Westwood Building Member
Acquisitions, dispositions and other transactions
Proceeds from sale of building						$ 65
Occidental Tower Building member \| Subsequent event
Acquisitions, dispositions and other transactions
Proceeds from sale of building			$ 85
Hugoton Field operations
Acquisitions, dispositions and other transactions
Pre-tax proceeds from sale of assets									$ 1,300	$ 1,400
Gain on sale of idled site									$ 531					$ 531
Williston operations
Acquisitions, dispositions and other transactions
Proceeds from sale of property held-for-sale					$ 590
Piceance operations
Acquisitions, dispositions and other transactions
Proceeds from sale of property held-for-sale				$ 155