INVESTMENTS AND RELATED-PARTY TRANSACTIONS (Details) shares in Millions, $ in Millions		1 Months Ended		12 Months Ended
	Nov. 30, 2014 shares	Mar. 31, 2016 USD ($) shares	Nov. 30, 2014 USD ($) shares	Dec. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
RELATED-PARTY TRANSACTIONS
Sales to related parties				$ 602	$ 555	$ 835
Purchases from related parties				7	26	6
Services				17	32	27
Advances and amounts due from related parties				59	60	26
Amounts due to related parties					5	15
Equity Method Investments
Equity method investment amounts				1,401	1,267	1,171
Equity investments dividends paid				224	438	396
Excess of investments in equity investees over the underlying equity in net assets				653
Excess of investments in equity investees over the underlying equity in net assets, which represents goodwill				537
Equity-method investments financial information summarized by Income Statement line item
Revenues				1,238	1,050	3,090
Costs and expenses				1,043	827	2,774
Net income				195	223	$ 316
Equity-method investments financial information summarized by Balance Sheet line item
Current assets				914	896
Non-current assets				3,605	3,589
Current liabilities				577	536
Long-term debt				1,957	2,141
Other non-current liabilities				159	149
Stockholders' equity				$ 1,826	$ 1,659
General Partner of Plains All American Pipeline,L.P
EQUITY INVESTMENTS
Ownership interest (as a percent)				12.00%
Proceeds from sale			$ 1,700
Gain on sale of equity investments			$ 1,400
RELATED-PARTY TRANSACTIONS
Sales to related party (as a percent)				89.00%	87.00%	46.00%
California Resource Corporation
EQUITY INVESTMENTS
Interest in investment recorded as available for sale asset (as a percent)	18.70%
Shares owned by Occidental | shares	71.5		71.5
Other than temporary loss		$ 78			$ 227
Available for sale investment					$ 167
California Resource Corporation | Stock dividend distribution
EQUITY INVESTMENTS
Stock dividend, shares distributed | shares		71.5
Dolphin Energy
EQUITY INVESTMENTS
Equity method investment ownership percentage				24.50%
Ownership interest (as a percent)				24.50%
Number of separate economic interests comprising investment in unconsolidated affiliate | item				2