PROPERTY, PLANT AND EQUIPMENT, NET (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Property, plant and equipment
Property, plant and equipment, at cost	$ 3,072.6	$ 3,070.4
Less: accumulated depreciation	1,430.9	1,404.7
Property, plant and equipment, net	1,641.7	1,665.7
Chemical manufacturing plants
Property, plant and equipment
Property, plant and equipment, at cost	1,388.7	1,398.5
Machinery and equipment
Property, plant and equipment
Property, plant and equipment, at cost	1,220.0	1,198.7
Buildings
Property, plant and equipment
Property, plant and equipment, at cost	195.5	202.8
Land and land improvements
Property, plant and equipment
Property, plant and equipment, at cost	176.9	185.7
Construction-in-progress
Property, plant and equipment
Property, plant and equipment, at cost	$ 91.5	$ 84.7