STOCK-BASED COMPENSATION (Employees' Stock Purchase Plan) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Additional Information about ESPP [Abstract]
Total Compensation Expense	$ 224	$ 359	$ 261
Stock-based compensation expense related tax benefit	$ 50	$ 133	$ 97
Employees' Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%
Plan price of the stock is set a no less than the following percentage of market price	85.00%
Additional Information about ESPP [Abstract]
Weighted-average fair value per share of purchase rights granted	$ 0.00	$ 10.70	$ 3.40
Total Compensation Expense	$ 0	$ 38	$ 7
Stock-based compensation expense related tax benefit	0	14	3
Total amount of cash received from the exercise of purchase rights	0	179	86
Total intrinsic value of purchase rights exercised	0	48	23
Total intrinsic value of purchase rights exercised, related tax benefit	$ 0	$ 18	$ 9

Additional Information about ESPP [Abstract]

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- Definition

Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Employee Stock Purchase Plan Purchase Rights Exercised.

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- Definition

The discount rate from market value that participants pay for shares.

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- Definition

The intrinsic value of equity-based payment equity instruments, excluding stock (or unit) options, that vested during the reporting period as calculated by applying the disclosed pricing methodology.

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- Definition

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

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- Definition

Amount of cash inflow from issuance of shares under share-based compensation arrangement, excluding stock option exercises.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

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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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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