Equity Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement, Equity Component [Roll Forward]
PolyOne Shareholders' Equity, Balance at the beginning			$ 776.3
Noncontrolling Interests, Balance at the beginning			0.9
Total Equity, Balance at the beginning			777.2	$ 978.5
PolyOne Shareholders' Equity, Net Income	$ 66.8	$ 31.7	97.0	61.1
Noncontrolling Interest, Net Income	0.2	(0.2)	0.2	(0.4)
Total Equity, Net income	67.0	31.5	97.2	60.7
Translation adjustments	3.3	1.1	(14.6)	0.4
Unrealized gain on available-for-sale securities	0.4	0.0	0.4	0.0
PolyOne Shareholders' Equity, Total comprehensive income	70.5	32.8	82.8	61.5
Noncontrolling Interests, Total comprehensive income	0.2	(0.2)	0.2	(0.4)
Total comprehensive income	70.7	32.6	83.0	61.1
Cash dividend declared			(17.8)	(15.0)
Repurchase of common shares			(42.8)	(119.9)
Share-based incentive plan activity			0.3	8.3
PolyOne Shareholders' Equity, Balance at the ending	798.8		798.8
Noncontrolling Interests, Balance at the ending	1.1		1.1
Total Equity, Balance at the ending	799.9	913.0	799.9	913.0
PolyOne Shareholders' Equity [Member]
Statement, Equity Component [Roll Forward]
PolyOne Shareholders' Equity, Balance at the beginning			776.3	976.8
PolyOne Shareholders' Equity, Net Income				61.1
Translation adjustments			(14.6)	0.4
Unrealized gain on available-for-sale securities			0.4
PolyOne Shareholders' Equity, Total comprehensive income			82.8	61.5
Cash dividend declared			(17.8)	(15.0)
Repurchase of common shares			(42.8)	(119.9)
Share-based incentive plan activity			0.3	8.3
PolyOne Shareholders' Equity, Balance at the ending	798.8	911.7	798.8	911.7
Noncontrolling Interests [Member]
Statement, Equity Component [Roll Forward]
Noncontrolling Interests, Balance at the beginning			0.9	1.7
Noncontrolling Interest, Net Income			0.2	(0.4)
Translation adjustments			0.0	0.0
Unrealized gain on available-for-sale securities			0.0
Noncontrolling Interests, Total comprehensive income			0.2	(0.4)
Cash dividend declared			0.0	0.0
Repurchase of common shares			0.0	0.0
Share-based incentive plan activity			0.0	0.0
Noncontrolling Interests, Balance at the ending	$ 1.1	$ 1.3	$ 1.1	$ 1.3