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

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-Publisher FASB
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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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STOCK INCENTIVE PLANS - Stock Options Outstanding and Exercisable (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number (in shares)	1,133,103	1,933,713	2,124,036	2,226,286
Options outstanding, weighted-average remaining contractual life (in years)	6 years 6 months 16 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 229.42
Options outstanding intrinsic value	$ 60
Options exercisable (in shares)	581,534
Options exercisable, weighted-average remaining contractual life (in years)	4 years 10 months 13 days
Options exercisable, weighted-average exercise price (in dollars per share)	$ 211.55
Options exercisable intrinsic value	$ 41
Range 1 of Exercise Prices [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (in dollars per share)	$ 72.14
Exercise price range, upper range limit (in dollars per share)	$ 204.01
Options outstanding, number (in shares)	184,435
Options outstanding, weighted-average remaining contractual life (in years)	2 years 2 months 23 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 152.28
Options outstanding intrinsic value	$ 24
Options exercisable (in shares)	183,292
Options exercisable, weighted-average remaining contractual life (in years)	2 years 2 months 8 days
Options exercisable, weighted-average exercise price (in dollars per share)	$ 152.17
Options exercisable intrinsic value	$ 24
Range 2 of Exercise Prices [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (in dollars per share)	$ 223.68
Exercise price range, upper range limit (in dollars per share)	$ 276.64
Options outstanding, number (in shares)	948,668
Options outstanding, weighted-average remaining contractual life (in years)	7 years 4 months 13 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 244.42
Options outstanding intrinsic value	$ 36
Options exercisable (in shares)	398,242
Options exercisable, weighted-average remaining contractual life (in years)	6 years 1 month 6 days
Options exercisable, weighted-average exercise price (in dollars per share)	$ 238.88
Options exercisable intrinsic value	$ 17