STOCK-BASED EMPLOYEE COMPENSATION (Stock Options) (Details) - Employee Stock Option [Member] - USD ($) $ / shares in Units, $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Number of Shares
Beginning balance (in shares)	27,263
Exercised (in shares)	(1,396)
Ending balance (in shares)	25,867		27,263
Weighted-average Exercise Price
Beginning balance (in dollars per share)	$ 387
Exercised (in dollars per share)	313
Ending balance (in dollars per share)	$ 391		$ 387
Aggregate Intrinsic Value	$ 38		$ 36
Weighted Average Remaining Contractual Term	2 years 2 months 12 days		2 years 9 months 18 days
Vested and exercisable at June 30, 2019
Number of Shares	25,867
Weighted Average Exercise Price (in dollars per share)	$ 391
Aggregate Intrinsic Value	$ 38
Weighted Average Remaining Contractual Term, Exercisable	2 years 2 months 12 days
Stock options exercised, total intrinsic value	$ 2	$ 4

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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