SHARE-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Tax benefit related to share-based compensation costs incurred			$ 4.0	$ 17.0
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	$ 14.0	$ 16.0	29.0	44.0
Tax benefit related to share-based compensation costs incurred	3.0	3.5		7.0
Fair value - vested during period			47.0	124.0
Unrecognized share-based compensation costs	121.0	115.0	$ 121.0	115.0
Unrecognized share-based compensation costs - weighted average period expected to be recognized			2 years 9 months
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	$ 13.0	$ 14.0	$ 13.0	$ 14.0
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)			(87)
Forfeited (in shares)			0
Nonvested restricted stock units (in shares) - end of period	247		247
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)			54.71
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)	$ 54.49		$ 54.49
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		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)			719
Vested (in shares)			(483)
Forfeited (in shares)			(47)
Nonvested restricted stock units (in shares) - end of period	1,544		1,544
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)			49.16
Weighted average grant date fair value - vested (in usd per share)			54.39
Weighted average grant date fair value - forfeited (in usd per share)			56.71
Weighted average grant date fair value - end of period (in usd per share)	$ 54.17		$ 54.17
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)			456
Vested (in shares)			(377)
Forfeited (in shares)			(47)
Nonvested restricted stock units (in shares) - end of period	1,020		1,020
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			$ 44.0
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