INCOME TAXES (Reconciliation to U.S. Statutory Rate) (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statutory U.S. federal income tax rate	21.00%	21.00%	35.00%
Equity earnings effect	(3.20%)	(3.30%)	(52.70%)
Foreign income taxed at rates other than the statutory U.S. federal income tax rate	(14.80%)	6.70%	(61.20%)
U.S. tax effect of foreign earnings and dividends	1.90%	(0.70%)	(8.40%)
Unrecognized tax benefits	1.00%	0.20%	13.50%
Acquisitions, divestitures and ownership restructuring activities	0.00%	0.80%	142.00%
Impact of tax reform 3	0.111	(0.034)	3.678
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Percent	10.40%	0.00%	0.00%
State and local income taxes	(4.40%)	0.40%	11.40%
Excess tax benefits from stock-based compensation	1.20%	(1.00%)	(39.70%)
Other - net	(14.90%)	0.90%	14.50%
Effective Tax Rate	(37.70%)	21.60%	643.00%
Sadara Chemical Company
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent	(29.50%)	0.00%	0.00%
Goodwill [Member]
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent	(17.50%)	0.00%	220.80%

Effective Income Tax Rate Reconciliation, Acquisitions, Divestitures, and Ownership Restructuring Activities, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to equity in earnings (loss) of unconsolidated subsidiaries exempt from income taxes.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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Percentage of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to Tax Cuts and Jobs Act.

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