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SHARE-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Restricted Stock And Restricted Stock Units
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Share based compensation expense incurred	$ 16	$ 29
Tax benefit related to share-based compensation costs incurred	2	7
Fair value - vested during period	42	120
Unrecognized share-based compensation costs	$ 137	130
Unrecognized share-based compensation costs - weighted average period expected to be recognized	3 years
Restricted Stock And Restricted Stock Units | Cash Settled
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Abstract]
Liability for cash-settled units	$ 9	$ 9
Performance Based Restricted Stock and Restricted Stock Units | Share Settled
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock units (in shares) - beginning of period	230
Granted (in shares)	104
Vested (in shares)	(51)
Forfeited (in shares)	0
Nonvested restricted stock units (in shares) - end of period	283
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Abstract]
Weighted average grant date fair value - beginning of period (in usd per share)	$ 57.08
Weighted average grant date fair value - granted (in usd per share)	48.89
Weighted average grant date fair value - vested (in usd per share)	53.81
Weighted average grant date fair value - forfeited (in usd per share)	0.00
Weighted average grant date fair value - end of period (in usd per share)	$ 54.68
Performance Based Restricted Stock and Restricted Stock Units | Cash Settled
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock units (in shares) - beginning of period	42
Granted (in shares)	0
Vested (in shares)	(12)
Forfeited (in shares)	0
Nonvested restricted stock units (in shares) - end of period	30
Service Based Restricted Stock And Restricted Stock Units | Share Settled
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock units (in shares) - beginning of period	1,355
Granted (in shares)	711
Vested (in shares)	(455)
Forfeited (in shares)	(20)
Nonvested restricted stock units (in shares) - end of period	1,591
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Abstract]
Weighted average grant date fair value - beginning of period (in usd per share)	$ 57.09
Weighted average grant date fair value - granted (in usd per share)	49.07
Weighted average grant date fair value - vested (in usd per share)	54.44
Weighted average grant date fair value - forfeited (in usd per share)	57.45
Weighted average grant date fair value - end of period (in usd per share)	$ 54.18
Service Based Restricted Stock And Restricted Stock Units | Cash Settled
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock units (in shares) - beginning of period	988
Granted (in shares)	449
Vested (in shares)	(360)
Forfeited (in shares)	(20)
Nonvested restricted stock units (in shares) - end of period	1,057
2014 Long Term Equity Compensation Plan | Restricted Stock And Restricted Stock Units
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Fair value - vested during period	$ 44
Cliff Vesting | 2014 Long Term Equity Compensation Plan | Restricted Stock And Restricted Stock Units
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Award vesting period	3 years

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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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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made 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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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