DOMESTIC AND FOREIGN INCOME TAXES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Domestic and foreign components of income from continuing operations before domestic and foreign income taxes
Income from continuing operations before income taxes, Domestic	$ (2,698.0)	$ (5,810.0)	$ (732.0)
Income from continuing operations before income taxes, Foreign	1,034.0	(3,666.0)	2,273.0
Pre-tax operating profit (loss)	(1,664.0)	(9,476.0)	1,541.0
Provisions (credits) for domestic and foreign income taxes on continuing operations
Current United States Federal tax expense (benefit)	(784.0)	(810.0)	870.0
Current State and Local tax expense (benefit)	9.0	(31.0)	81.0
Current Foreign tax expense (benefit)	630.0	883.0	1,912.0
Current Total tax expense (benefit)	(145.0)	42.0	2,863.0
Deferred United States Federal tax expense (benefit)	(505.0)	(1,146.0)	(1,037.0)
Deferred State and Local tax expense (benefit)	(19.0)	(83.0)	(71.0)
Deferred Foreign tax expense (benefit)	7.0	(143.0)	(70.0)
Deferred Total tax expense (benefit)	(517.0)	(1,372.0)	(1,178.0)
United States Federal Total tax expense (benefit)	(1,289.0)	(1,956.0)	(167.0)
State and Local Total tax expense (benefit)	(10.0)	(114.0)	10.0
Foreign Total tax expense (benefit)	637.0	740.0	1,842.0
Total tax expense (benefit)	$ (662.0)	$ (1,330.0)	$ 1,685.0
Reconciliation of the United States federal statutory income tax rate to Occidental's worldwide effective tax rate on income from continuing operations
United States federal statutory tax rate (as a percent)	35.00%	35.00%	35.00%
Other than temporary loss on available for sale investment in California Resources stock (as a percent)	(2.00%)	(1.00%)	12.00%
Enhanced oil recovery credit	5.00%
Tax benefit due to write off of exploration blocks	14.00%
Operations outside the United States (as a percent)	(14.00%)	(21.00%)	65.00%
State income taxes, net of federal benefit (as a percent)		1.00%	1.00%
Other (as a percent)	2.00%		(4.00%)
Worldwide effective tax rate (as a percent)	40.00%	14.00%	109.00%
Deferred Tax Assets and Liabilities
Deferred Tax Assets, environmental reserves	$ 314.0	$ 136.0
Deferred Tax Assets, postretirement benefit accruals	342.0	346.0
Deferred Tax Assets, deferred compensation and benefits	222.0	179.0
Deferred Tax Assets, asset retirement obligations	406.0	372.0
Deferred Tax Assets, foreign tax credit carryforwards	2,046.0	2,034.0
Deferred Tax Assets, Alternative minimum tax credit carryforwards	226.0
Deferred Tax Assets, General business credit carryforwards	186.0
Deferred tax Assets, federal benefit of state income taxes	8.0	11.0
Deferred Tax Assets, all other	370.0	677.0
Deferred Tax Assets, subtotal	4,120.0	3,755.0
Deferred Tax Assets, valuation allowance	(1,849.0)	(1,834.0)
Deferred Tax Assets, total deferred taxes	2,271.0	1,921.0
Deferred Tax Liabilities, property, plant and equipment differences	3,345.0	3,232.0
Deferred Tax Liabilities, equity investments, partnerships and foreign subsidiaries	58.0	12.0
Deferred Tax Liabilities, total deferred taxes	3,403.0	3,244.0
Unremitted earnings of certain consolidated foreign subsidiaries	8,500.0
Deferred tax liability not recognized, indefinitely reinvested foreign earnings	116.0
Discontinued operations income tax charges (benefits)	249.0	1.0	$ 454.0
Unrecognized tax benefits included in deferred credits and other liabilities - other that would affect effective tax rate	22.0
Reconciliation of unrecognized tax benefits
Balance, at beginning of period	22.0	61.0
Reductions based on tax positions related to prior years and settlements		(39.0)
Balance, at end of period	22.0	22.0	$ 61.0
Other current assets
Reconciliation of unrecognized tax benefits
Income tax receivables	$ 761.0	$ 297.0