SHARE-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restricted Stock And Restricted Stock Units [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Share based compensation expense incurred	$ 16.0	$ 19.0	$ 44.0	$ 36.0
Tax benefit related to share-based compensation costs incurred	3.5	5.0	17.0	8.0
Fair value - vested during period			124.0	62.0
Unrecognized share-based compensation costs	115.0		$ 115.0
Unrecognized share-based compensation costs - weighted average period expected to be recognized			2 years 8 months 12 days
Restricted Stock And Restricted Stock Units [Member] | Cash Settled [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Abstract]
Liability for cash-settled units	$ 14.0	$ 30.0	$ 14.0	$ 30.0
Performance Based Restricted Stock and Restricted Stock Units [Member] | Share Settled [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock (in shares) - beginning of period			283,000
Granted (in shares)			87,000
Vested (in shares)			(119,000)
Forfeited (in shares)			0
Nonvested restricted stock (in shares) - end of period	251,000		251,000
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)			$ 51.27
Weighted average grant date fair value - granted (in usd per share)			64.58
Weighted average grant date fair value - vested (in usd per share)			49.14
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)	$ 56.88		$ 56.88
Performance Based Restricted Stock and Restricted Stock Units [Member] | Cash Settled [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock (in shares) - beginning of period			68,000
Granted (in shares)			15,000
Vested (in shares)			(38,000)
Forfeited (in shares)			0
Nonvested restricted stock (in shares) - end of period	45,000		45,000
Restricted Stock Units (RSUs) [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Tax benefit related to share-based compensation costs incurred			$ 7.0
Service Based Restricted Stock And Restricted Stock Units [Member] | Share Settled [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock (in shares) - beginning of period			1,593,000
Granted (in shares)			521,000
Vested (in shares)			(876,000)
Forfeited (in shares)			(37,000)
Nonvested restricted stock (in shares) - end of period	1,201,000		1,201,000
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)			$ 48.88
Weighted average grant date fair value - granted (in usd per share)			64.23
Weighted average grant date fair value - vested (in usd per share)			47.38
Weighted average grant date fair value - forfeited (in usd per share)			54.89
Weighted average grant date fair value - end of period (in usd per share)	$ 56.96		$ 56.96
Service Based Restricted Stock And Restricted Stock Units [Member] | Cash Settled [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Nonvested restricted stock (in shares) - beginning of period			1,392,000
Granted (in shares)			425,000
Vested (in shares)			(751,000)
Forfeited (in shares)			(37,000)
Nonvested restricted stock (in shares) - end of period	1,029,000		1,029,000
2014 Long Term Equity Compensation Plan [Member] | Restricted Stock And Restricted Stock Units [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Fair value - vested during period			$ 44.0
Cliff Vesting [Member] | 2014 Long Term Equity Compensation Plan [Member] | Restricted Stock And Restricted Stock Units [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Cliff Vesting [Member] | 2014 Long Term Equity Compensation Plan [Member] | Service Based Restricted Stock And Restricted Stock Units [Member] | Share Settled [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Vested (in shares)			(313,391)
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Cliff Vesting [Member] | 2014 Long Term Equity Compensation Plan [Member] | Service Based Restricted Stock And Restricted Stock Units [Member] | Cash Settled [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Roll Forward]
Vested (in shares)			(307,556)
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years