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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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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). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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