OTHER ASSETS (Details Textuals) - USD ($) $ in Millions		12 Months Ended
	Oct. 05, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Combination, Separately Recognized Transactions [Line Items]
Up-front payments under the ethylene agreements	$ 433.5
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Ethylene Asset	416.1
2017 Supply Contract Payment		$ 209.4
Payments under long-term supply contract		175.7	$ 0.0	$ 0.0
Amortization of Supply Contracts		21.5	4.3
Supply Contract Amortization Expense Next Twelve Months		25.0
Supply Contract Amortization Expense, Year 2		25.0
Supply Contract Amortization Expense, Year 3		25.0
Supply Contract Amortization Expense, Year 4		25.0
Supply Contract Amortization Expense, Year 5		$ 25.0
Minimum
Business Combination, Separately Recognized Transactions [Line Items]
Q4 2020 Supply Contract Payment			425.0
Maximum
Business Combination, Separately Recognized Transactions [Line Items]
Q4 2020 Supply Contract Payment			$ 465.0
DCP Business
Business Combination, Separately Recognized Transactions [Line Items]
Up-front payments under the ethylene agreements	$ 433.5