STOCK-BASED COMPENSATION (Accounting for Stock-Based Compensation) (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($) employees $ / shares shares	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Plan Modification, Incremental Cost	$ 0
Share-based Payment Arrangement, Expense	158	$ 188	$ 310
Share-based Payment Arrangement, Expense, Tax Benefit	$ 36	$ 42	$ 115
Dividend yield	5.10%	2.13%	3.01%
Expected volatility	26.10%	23.34%	23.71%
Risk-free interest rate	2.43%	2.83%	1.28%
Common Stock, Dividends, Per Share, Cash Paid \| $ / shares	$ 0.70	$ 0.38	$ 0.46
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 23	$ 68	$ 37
Share-based Payment Arrangement, Expense, Tax Benefit	$ 5	$ 15	$ 14
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 years 1 month 6 days	6 years 2 months 12 days	7 years 6 months
Employee Stock Option \| 2019 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant \| shares	25
Employees' Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense			$ 38
Share-based Payment Arrangement, Expense, Tax Benefit			$ 14
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	0 months	0 months	3 months
Dow Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Plan Modification, Number of Grantees Affected \| employees	5,000
Corteva [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Plan Modification, Number of Grantees Affected \| employees	4,000

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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Number of grantees affected by modification of award under share-based payment arrangement.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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