PENSIONS AND POSTRETIREMENT BENEFITS (Effect of Fair Value Measurements Using Significant Unobservable Inputs (Level 3) on Changes in Pension Plan Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Fair value of plan assets — beginning of year	$ 193.4	$ 188.1
Actual return on plan assets:
Relating to assets still held at the reporting date	12.3	5.5
Purchases	8.0	5.7
Sales	14.6	8.4
Fair value of plan assets — end of year	202.4	193.4
Hedge Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Fair value of plan assets — beginning of year	40.7	41.5
Actual return on plan assets:
Relating to assets still held at the reporting date	(0.1)	(0.8)
Purchases	0.0	0.0
Sales	0.0	0.0
Fair value of plan assets — end of year	40.6	40.7
Private Equity Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Fair value of plan assets — beginning of year	33.1	31.2
Actual return on plan assets:
Relating to assets still held at the reporting date	(2.7)	1.5
Purchases	8.0	5.7
Sales	6.0	7.8
Fair value of plan assets — end of year	36.1	33.1
Structured Finance [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Fair value of plan assets — beginning of year	62.1	65.4
Actual return on plan assets:
Relating to assets still held at the reporting date	10.0	(3.3)
Purchases	0.0	0.0
Sales	8.0	0.0
Fair value of plan assets — end of year	63.8	62.1
Real Estate [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Roll Forward]
Fair value of plan assets — beginning of year	57.5	50.0
Actual return on plan assets:
Relating to assets still held at the reporting date	5.1	8.1
Purchases	0.0	0.0
Sales	0.6	0.6
Fair value of plan assets — end of year	$ 61.9	$ 57.5