Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Sales	$ 861.5	$ 887.1	$ 1,708.5	$ 1,760.2
Cost of sales	669.2	701.4	1,330.7	1,404.7
Gross margin	192.3	185.7	377.8	355.5
Selling and administrative expense	110.8	105.4	225.0	205.1
Operating income	81.5	80.3	152.8	150.4
Interest expense, net	(14.6)	(16.2)	(29.2)	(32.3)
Debt extinguishment costs	(0.4)	0.0	(0.4)	0.0
Other income (expense), net	0.1	(0.7)	0.4	(1.4)
Income before income taxes	66.6	63.4	123.6	116.7
Income tax (expense) benefit	(16.6)	3.6	(34.6)	(19.5)
Net income	50.0	67.0	89.0	97.2
Net (income) loss attributable to noncontrolling interests	0.0	(0.2)	0.1	(0.2)
Net income attributable to PolyOne common shareholders	$ 50.0	$ 66.8	$ 89.1	$ 97.0
Earnings per common share attributable to PolyOne common shareholders - Basic (in USD per share)	$ 0.59	$ 0.75	$ 1.06	$ 1.09
Earnings per common share attributable to PolyOne common shareholders - Diluted (in USD per share)	$ 0.59	$ 0.74	$ 1.05	$ 1.08
Weighted-average shares used to compute earnings per common share:
Basic (in shares)	84.1	88.9	84.4	89.1
Diluted (in shares)	84.7	89.8	84.9	89.9
Cash dividends declared per share of common stock (in USD per share)	$ 0.12	$ 0.10	$ 0.24	$ 0.20