STOCK-BASED COMPENSATION (Accounting for Stock-Based Compensation) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 224	$ 359	$ 261
Dividend yield	2.13%	3.01%	4.13%
Expected volatility	23.34%	23.71%	31.60%
Risk-free interest rate	2.83%	1.28%	1.12%
Dividends paid (in dollars per share)	$ 0.38	$ 0.46	$ 0.46
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 50	$ 133	$ 97
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 68	$ 37	$ 32
Expected life of award	6 years 2 months 12 days	7 years 6 months	7 years 9 months 18 days
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 15	$ 14	$ 12
Employees' Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	0	$ 38	$ 7
Expected life of award		3 years	4 years
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 0	$ 14	$ 3

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

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

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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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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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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