CREDIT FACILITIES (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)
Short-term Debt [Line Items]
Ratio of Indebtedness to Net Capital	0.4
Commercial paper maximum borrowing capacity	$ 700.0
Short-term Debt	79.0
Letters of Credit Outstanding, Amount	1.8
Line of Credit Facility, Remaining Borrowing Capacity	$ 619.2