Business Combinations Narrative (Details) - USD ($) $ in Millions			3 Months Ended
	Jan. 29, 2016	Dec. 09, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill			$ 634.8		$ 597.7	$ 590.6
Business acquisitions			$ 72.8	$ 0.0
Magenta
Business Acquisition [Line Items]
Payment to acquire business, net of cash acquired		$ 18.1
Goodwill		$ 6.6
Kraton
Business Acquisition [Line Items]
Business acquisitions	$ 72.8
Goodwill acquired	36.9
Intangible assets acquired	$ 13.8
Kraton | Minimum
Business Acquisition [Line Items]
Intangible assets acquired, amortization period	7 years
Kraton | Maximum
Business Acquisition [Line Items]
Intangible assets acquired, amortization period	10 years